diff --git a/java/com/google/gerrit/plugins/codeowners/backend/FileCodeOwnerStatus.java b/java/com/google/gerrit/plugins/codeowners/backend/FileCodeOwnerStatus.java
index 34ff019..330917d 100644
--- a/java/com/google/gerrit/plugins/codeowners/backend/FileCodeOwnerStatus.java
+++ b/java/com/google/gerrit/plugins/codeowners/backend/FileCodeOwnerStatus.java
@@ -14,8 +14,13 @@
 
 package com.google.gerrit.plugins.codeowners.backend;
 
+import static java.util.Objects.requireNonNull;
+
 import com.google.auto.value.AutoValue;
 import com.google.gerrit.plugins.codeowners.common.ChangedFile;
+import com.google.gerrit.plugins.codeowners.common.CodeOwnerStatus;
+import com.google.gerrit.plugins.codeowners.util.JgitPath;
+import java.nio.file.Path;
 import java.util.Optional;
 
 /** Code owner status for a particular file that was changed in a change. */
@@ -56,4 +61,77 @@
     return new AutoValue_FileCodeOwnerStatus(
         changedFile, newPathCodeOwnerStatus, oldPathCodeOwnerStatus);
   }
+
+  public static FileCodeOwnerStatus addition(String path, CodeOwnerStatus codeOwnerStatus) {
+    requireNonNull(path, "path");
+
+    return addition(JgitPath.of(path).getAsAbsolutePath(), codeOwnerStatus);
+  }
+
+  public static FileCodeOwnerStatus addition(Path path, CodeOwnerStatus codeOwnerStatus) {
+    requireNonNull(path, "path");
+    requireNonNull(codeOwnerStatus, "codeOwnerStatus");
+
+    return create(
+        ChangedFile.addition(path),
+        Optional.of(PathCodeOwnerStatus.create(path, codeOwnerStatus)),
+        Optional.empty());
+  }
+
+  public static FileCodeOwnerStatus modification(Path path, CodeOwnerStatus codeOwnerStatus) {
+    requireNonNull(path, "path");
+    requireNonNull(codeOwnerStatus, "codeOwnerStatus");
+
+    return create(
+        ChangedFile.modification(path),
+        Optional.of(PathCodeOwnerStatus.create(path, codeOwnerStatus)),
+        Optional.empty());
+  }
+
+  public static FileCodeOwnerStatus deletion(String path, CodeOwnerStatus codeOwnerStatus) {
+    requireNonNull(path, "path");
+
+    return deletion(JgitPath.of(path).getAsAbsolutePath(), codeOwnerStatus);
+  }
+
+  public static FileCodeOwnerStatus deletion(Path path, CodeOwnerStatus codeOwnerStatus) {
+    requireNonNull(path, "path");
+    requireNonNull(codeOwnerStatus, "codeOwnerStatus");
+
+    return create(
+        ChangedFile.deletion(path),
+        Optional.empty(),
+        Optional.of(PathCodeOwnerStatus.create(path, codeOwnerStatus)));
+  }
+
+  public static FileCodeOwnerStatus rename(
+      String oldPath,
+      CodeOwnerStatus oldPathCodeOwnerStatus,
+      String newPath,
+      CodeOwnerStatus newPathCodeOwnerStatus) {
+    requireNonNull(oldPath, "oldPath");
+    requireNonNull(newPath, "newPath");
+
+    return rename(
+        JgitPath.of(oldPath).getAsAbsolutePath(),
+        oldPathCodeOwnerStatus,
+        JgitPath.of(newPath).getAsAbsolutePath(),
+        newPathCodeOwnerStatus);
+  }
+
+  public static FileCodeOwnerStatus rename(
+      Path oldPath,
+      CodeOwnerStatus oldPathCodeOwnerStatus,
+      Path newPath,
+      CodeOwnerStatus newPathCodeOwnerStatus) {
+    requireNonNull(oldPath, "oldPath");
+    requireNonNull(oldPathCodeOwnerStatus, "oldPathCodeOwnerStatus");
+    requireNonNull(newPath, "newPath");
+    requireNonNull(newPathCodeOwnerStatus, "newPathCodeOwnerStatus");
+
+    return create(
+        ChangedFile.rename(newPath, oldPath),
+        Optional.of(PathCodeOwnerStatus.create(newPath, newPathCodeOwnerStatus)),
+        Optional.of(PathCodeOwnerStatus.create(oldPath, oldPathCodeOwnerStatus)));
+  }
 }
diff --git a/java/com/google/gerrit/plugins/codeowners/backend/PathCodeOwnerStatus.java b/java/com/google/gerrit/plugins/codeowners/backend/PathCodeOwnerStatus.java
index 9f4b87e..b5f0976 100644
--- a/java/com/google/gerrit/plugins/codeowners/backend/PathCodeOwnerStatus.java
+++ b/java/com/google/gerrit/plugins/codeowners/backend/PathCodeOwnerStatus.java
@@ -14,8 +14,11 @@
 
 package com.google.gerrit.plugins.codeowners.backend;
 
+import static java.util.Objects.requireNonNull;
+
 import com.google.auto.value.AutoValue;
 import com.google.gerrit.plugins.codeowners.common.CodeOwnerStatus;
+import com.google.gerrit.plugins.codeowners.util.JgitPath;
 import java.nio.file.Path;
 
 /** Code owner status for a particular path that has been modified in a change. */
@@ -41,4 +44,18 @@
   public static PathCodeOwnerStatus create(Path path, CodeOwnerStatus codeOwnerStatus) {
     return new AutoValue_PathCodeOwnerStatus(path, codeOwnerStatus);
   }
+
+  /**
+   * Creates a {@link PathCodeOwnerStatus} instance.
+   *
+   * @param path the path to which the code owner status belongs
+   * @param codeOwnerStatus the code owner status
+   * @return the created {@link PathCodeOwnerStatus} instance
+   */
+  public static PathCodeOwnerStatus create(String path, CodeOwnerStatus codeOwnerStatus) {
+    requireNonNull(path, "path");
+    requireNonNull(codeOwnerStatus, "codeOwnerStatus");
+
+    return create(JgitPath.of(path).getAsAbsolutePath(), codeOwnerStatus);
+  }
 }
diff --git a/java/com/google/gerrit/plugins/codeowners/common/ChangedFile.java b/java/com/google/gerrit/plugins/codeowners/common/ChangedFile.java
index 3d2caec..f66c31b 100644
--- a/java/com/google/gerrit/plugins/codeowners/common/ChangedFile.java
+++ b/java/com/google/gerrit/plugins/codeowners/common/ChangedFile.java
@@ -161,4 +161,38 @@
   private static Optional<Path> convertPathFromPatchListEntry(@Nullable String path) {
     return Optional.ofNullable(path).map(newName -> JgitPath.of(newName).getAsAbsolutePath());
   }
+
+  public static ChangedFile create(
+      Optional<String> newPath, Optional<String> oldPath, ChangeType changeType) {
+    requireNonNull(changeType, "changeType");
+
+    return new AutoValue_ChangedFile(
+        newPath.map(JgitPath::of).map(JgitPath::getAsAbsolutePath),
+        oldPath.map(JgitPath::of).map(JgitPath::getAsAbsolutePath),
+        changeType);
+  }
+
+  public static ChangedFile addition(Path newPath) {
+    requireNonNull(newPath, "newPath");
+
+    return new AutoValue_ChangedFile(Optional.of(newPath), Optional.empty(), ChangeType.ADD);
+  }
+
+  public static ChangedFile modification(Path path) {
+    requireNonNull(path, "path");
+
+    return new AutoValue_ChangedFile(Optional.of(path), Optional.of(path), ChangeType.MODIFY);
+  }
+
+  public static ChangedFile deletion(Path path) {
+    requireNonNull(path, "path");
+
+    return new AutoValue_ChangedFile(Optional.empty(), Optional.of(path), ChangeType.DELETE);
+  }
+
+  public static ChangedFile rename(Path newPath, Path oldPath) {
+    requireNonNull(newPath, "newPath");
+
+    return new AutoValue_ChangedFile(Optional.of(newPath), Optional.of(oldPath), ChangeType.RENAME);
+  }
 }
diff --git a/java/com/google/gerrit/plugins/codeowners/testing/BUILD b/java/com/google/gerrit/plugins/codeowners/testing/BUILD
index 16af5f4..202e994 100644
--- a/java/com/google/gerrit/plugins/codeowners/testing/BUILD
+++ b/java/com/google/gerrit/plugins/codeowners/testing/BUILD
@@ -13,6 +13,7 @@
         "//java/com/google/gerrit/extensions:api",
         "//java/com/google/gerrit/truth",
         "//lib:guava",
+        "//lib:jgit",
         "//lib/truth",
         "//lib/truth:truth-java8-extension",
         "//plugins/code-owners/java/com/google/gerrit/plugins/codeowners/api",
diff --git a/java/com/google/gerrit/plugins/codeowners/testing/FileCodeOwnerStatusInfoSubject.java b/java/com/google/gerrit/plugins/codeowners/testing/FileCodeOwnerStatusInfoSubject.java
index 26d3483..5f885e7 100644
--- a/java/com/google/gerrit/plugins/codeowners/testing/FileCodeOwnerStatusInfoSubject.java
+++ b/java/com/google/gerrit/plugins/codeowners/testing/FileCodeOwnerStatusInfoSubject.java
@@ -17,17 +17,72 @@
 import static com.google.common.truth.Truth.assertAbout;
 import static com.google.gerrit.plugins.codeowners.testing.PathCodeOwnerStatusInfoSubject.pathCodeOwnerStatusInfos;
 import static com.google.gerrit.truth.OptionalSubject.optionals;
+import static java.util.Objects.requireNonNull;
 
+import com.google.common.collect.ImmutableMap;
+import com.google.common.collect.Maps;
 import com.google.common.truth.ComparableSubject;
+import com.google.common.truth.Correspondence;
 import com.google.common.truth.FailureMetadata;
 import com.google.common.truth.Subject;
 import com.google.gerrit.extensions.common.ChangeType;
 import com.google.gerrit.plugins.codeowners.api.FileCodeOwnerStatusInfo;
+import com.google.gerrit.plugins.codeowners.api.PathCodeOwnerStatusInfo;
+import com.google.gerrit.plugins.codeowners.backend.FileCodeOwnerStatus;
+import com.google.gerrit.plugins.codeowners.backend.PathCodeOwnerStatus;
+import com.google.gerrit.plugins.codeowners.common.ChangedFile;
+import com.google.gerrit.truth.NullAwareCorrespondence;
 import com.google.gerrit.truth.OptionalSubject;
 import java.util.Optional;
+import org.eclipse.jgit.diff.DiffEntry;
 
 /** {@link Subject} for doing assertions on {@link FileCodeOwnerStatusInfo}s. */
 public class FileCodeOwnerStatusInfoSubject extends Subject {
+  private static final ImmutableMap<ChangeType, DiffEntry.ChangeType> CHANGE_TYPE =
+      Maps.immutableEnumMap(
+          new ImmutableMap.Builder<ChangeType, DiffEntry.ChangeType>()
+              .put(ChangeType.ADDED, DiffEntry.ChangeType.ADD)
+              .put(ChangeType.MODIFIED, DiffEntry.ChangeType.MODIFY)
+              .put(ChangeType.DELETED, DiffEntry.ChangeType.DELETE)
+              .put(ChangeType.RENAMED, DiffEntry.ChangeType.RENAME)
+              .put(ChangeType.COPIED, DiffEntry.ChangeType.COPY)
+              .build());
+
+  /**
+   * {@link Correspondence} that maps {@link FileCodeOwnerStatusInfo}s to {@link
+   * FileCodeOwnerStatus}s.
+   */
+  public static final Correspondence<FileCodeOwnerStatusInfo, FileCodeOwnerStatus>
+      isFileCodeOwnerStatus() {
+    return NullAwareCorrespondence.transforming(
+        FileCodeOwnerStatusInfoSubject::toFileCodeOwnerStatus, "is file code owner status");
+  }
+
+  private static FileCodeOwnerStatus toFileCodeOwnerStatus(
+      FileCodeOwnerStatusInfo fileCodeOwnerStatusInfo) {
+    requireNonNull(fileCodeOwnerStatusInfo, "fileCodeOwnerStatusInfo");
+
+    ChangedFile changedFile =
+        ChangedFile.create(
+            Optional.ofNullable(fileCodeOwnerStatusInfo.newPathStatus)
+                .map(pathCodeOwnerStatusInfo -> pathCodeOwnerStatusInfo.path),
+            Optional.ofNullable(fileCodeOwnerStatusInfo.oldPathStatus)
+                .map(pathCodeOwnerStatusInfo -> pathCodeOwnerStatusInfo.path),
+            CHANGE_TYPE.get(fileCodeOwnerStatusInfo.changeType));
+    return FileCodeOwnerStatus.create(
+        changedFile,
+        Optional.ofNullable(fileCodeOwnerStatusInfo.newPathStatus)
+            .map(FileCodeOwnerStatusInfoSubject::toPathCodeOwnerStatus),
+        Optional.ofNullable(fileCodeOwnerStatusInfo.oldPathStatus)
+            .map(FileCodeOwnerStatusInfoSubject::toPathCodeOwnerStatus));
+  }
+
+  private static PathCodeOwnerStatus toPathCodeOwnerStatus(
+      PathCodeOwnerStatusInfo pathCodeOwnerStatusInfo) {
+    requireNonNull(pathCodeOwnerStatusInfo, "pathCodeOwnerStatusInfo");
+    return PathCodeOwnerStatus.create(pathCodeOwnerStatusInfo.path, pathCodeOwnerStatusInfo.status);
+  }
+
   /**
    * Starts fluent chain to do assertions on a {@link FileCodeOwnerStatusInfo}.
    *
diff --git a/javatests/com/google/gerrit/plugins/codeowners/acceptance/api/GetCodeOwnerStatusIT.java b/javatests/com/google/gerrit/plugins/codeowners/acceptance/api/GetCodeOwnerStatusIT.java
index 01d3687..3cea3f4 100644
--- a/javatests/com/google/gerrit/plugins/codeowners/acceptance/api/GetCodeOwnerStatusIT.java
+++ b/javatests/com/google/gerrit/plugins/codeowners/acceptance/api/GetCodeOwnerStatusIT.java
@@ -15,15 +15,15 @@
 package com.google.gerrit.plugins.codeowners.acceptance.api;
 
 import static com.google.gerrit.plugins.codeowners.testing.CodeOwnerStatusInfoSubject.assertThat;
+import static com.google.gerrit.plugins.codeowners.testing.FileCodeOwnerStatusInfoSubject.isFileCodeOwnerStatus;
 
 import com.google.gerrit.acceptance.PushOneCommit;
 import com.google.gerrit.acceptance.TestAccount;
 import com.google.gerrit.acceptance.testsuite.request.RequestScopeOperations;
-import com.google.gerrit.extensions.common.ChangeType;
 import com.google.gerrit.plugins.codeowners.acceptance.AbstractCodeOwnersIT;
 import com.google.gerrit.plugins.codeowners.api.CodeOwnerStatusInfo;
+import com.google.gerrit.plugins.codeowners.backend.FileCodeOwnerStatus;
 import com.google.gerrit.plugins.codeowners.common.CodeOwnerStatus;
-import com.google.gerrit.plugins.codeowners.testing.FileCodeOwnerStatusInfoSubject;
 import com.google.inject.Inject;
 import org.junit.Test;
 
@@ -60,15 +60,11 @@
     assertThat(codeOwnerStatus)
         .hasPatchSetNumberThat()
         .isEqualTo(r.getChange().currentPatchSet().id().get());
-    FileCodeOwnerStatusInfoSubject fileCodeOwnerStatusInfoSubject =
-        assertThat(codeOwnerStatus).hasFileCodeOwnerStatusesThat().onlyElement();
-    fileCodeOwnerStatusInfoSubject.hasChangeTypeThat().isEqualTo(ChangeType.ADDED);
-    fileCodeOwnerStatusInfoSubject.hasNewPathStatusThat().value().hasPathThat().isEqualTo(path);
-    fileCodeOwnerStatusInfoSubject
-        .hasNewPathStatusThat()
-        .value()
-        .hasStatusThat()
-        .isEqualTo(CodeOwnerStatus.PENDING);
+
+    assertThat(codeOwnerStatus)
+        .hasFileCodeOwnerStatusesThat()
+        .comparingElementsUsing(isFileCodeOwnerStatus())
+        .containsExactly(FileCodeOwnerStatus.addition(path, CodeOwnerStatus.PENDING));
   }
 
   @Test
@@ -84,73 +80,34 @@
 
     CodeOwnerStatusInfo codeOwnerStatus =
         changeCodeOwnersApiFactory.change(changeId).getCodeOwnerStatus();
-    assertThat(codeOwnerStatus).hasFileCodeOwnerStatusesThat().hasSize(2);
-    FileCodeOwnerStatusInfoSubject fileCodeOwnerStatusInfoSubject1 =
-        assertThat(codeOwnerStatus).hasFileCodeOwnerStatusesThat().element(0);
-    fileCodeOwnerStatusInfoSubject1.hasChangeTypeThat().isEqualTo(ChangeType.DELETED);
-    fileCodeOwnerStatusInfoSubject1.hasOldPathStatusThat().value().hasPathThat().isEqualTo(oldPath);
-    fileCodeOwnerStatusInfoSubject1
-        .hasOldPathStatusThat()
-        .value()
-        .hasStatusThat()
-        .isEqualTo(CodeOwnerStatus.INSUFFICIENT_REVIEWERS);
-    FileCodeOwnerStatusInfoSubject fileCodeOwnerStatusInfoSubject2 =
-        assertThat(codeOwnerStatus).hasFileCodeOwnerStatusesThat().element(1);
-    fileCodeOwnerStatusInfoSubject2.hasChangeTypeThat().isEqualTo(ChangeType.ADDED);
-    fileCodeOwnerStatusInfoSubject2.hasNewPathStatusThat().value().hasPathThat().isEqualTo(newPath);
-    fileCodeOwnerStatusInfoSubject2
-        .hasNewPathStatusThat()
-        .value()
-        .hasStatusThat()
-        .isEqualTo(CodeOwnerStatus.INSUFFICIENT_REVIEWERS);
+    assertThat(codeOwnerStatus)
+        .hasFileCodeOwnerStatusesThat()
+        .comparingElementsUsing(isFileCodeOwnerStatus())
+        .containsExactly(
+            FileCodeOwnerStatus.deletion(oldPath, CodeOwnerStatus.INSUFFICIENT_REVIEWERS),
+            FileCodeOwnerStatus.addition(newPath, CodeOwnerStatus.INSUFFICIENT_REVIEWERS));
 
     // Add a reviewer that is a code owner of the old path.
     gApi.changes().id(changeId).addReviewer(user.email());
 
     codeOwnerStatus = changeCodeOwnersApiFactory.change(changeId).getCodeOwnerStatus();
-    assertThat(codeOwnerStatus).hasFileCodeOwnerStatusesThat().hasSize(2);
-    fileCodeOwnerStatusInfoSubject1 =
-        assertThat(codeOwnerStatus).hasFileCodeOwnerStatusesThat().element(0);
-    fileCodeOwnerStatusInfoSubject1.hasChangeTypeThat().isEqualTo(ChangeType.DELETED);
-    fileCodeOwnerStatusInfoSubject1.hasOldPathStatusThat().value().hasPathThat().isEqualTo(oldPath);
-    fileCodeOwnerStatusInfoSubject1
-        .hasOldPathStatusThat()
-        .value()
-        .hasStatusThat()
-        .isEqualTo(CodeOwnerStatus.PENDING);
-    fileCodeOwnerStatusInfoSubject2 =
-        assertThat(codeOwnerStatus).hasFileCodeOwnerStatusesThat().element(1);
-    fileCodeOwnerStatusInfoSubject2.hasChangeTypeThat().isEqualTo(ChangeType.ADDED);
-    fileCodeOwnerStatusInfoSubject2.hasNewPathStatusThat().value().hasPathThat().isEqualTo(newPath);
-    fileCodeOwnerStatusInfoSubject2
-        .hasNewPathStatusThat()
-        .value()
-        .hasStatusThat()
-        .isEqualTo(CodeOwnerStatus.INSUFFICIENT_REVIEWERS);
+    assertThat(codeOwnerStatus)
+        .hasFileCodeOwnerStatusesThat()
+        .comparingElementsUsing(isFileCodeOwnerStatus())
+        .containsExactly(
+            FileCodeOwnerStatus.deletion(oldPath, CodeOwnerStatus.PENDING),
+            FileCodeOwnerStatus.addition(newPath, CodeOwnerStatus.INSUFFICIENT_REVIEWERS));
 
     // Add a reviewer that is a code owner of the new path.
     gApi.changes().id(changeId).addReviewer(user2.email());
 
     codeOwnerStatus = changeCodeOwnersApiFactory.change(changeId).getCodeOwnerStatus();
-    assertThat(codeOwnerStatus).hasFileCodeOwnerStatusesThat().hasSize(2);
-    fileCodeOwnerStatusInfoSubject1 =
-        assertThat(codeOwnerStatus).hasFileCodeOwnerStatusesThat().element(0);
-    fileCodeOwnerStatusInfoSubject1.hasChangeTypeThat().isEqualTo(ChangeType.DELETED);
-    fileCodeOwnerStatusInfoSubject1.hasOldPathStatusThat().value().hasPathThat().isEqualTo(oldPath);
-    fileCodeOwnerStatusInfoSubject1
-        .hasOldPathStatusThat()
-        .value()
-        .hasStatusThat()
-        .isEqualTo(CodeOwnerStatus.PENDING);
-    fileCodeOwnerStatusInfoSubject2 =
-        assertThat(codeOwnerStatus).hasFileCodeOwnerStatusesThat().element(1);
-    fileCodeOwnerStatusInfoSubject2.hasChangeTypeThat().isEqualTo(ChangeType.ADDED);
-    fileCodeOwnerStatusInfoSubject2.hasNewPathStatusThat().value().hasPathThat().isEqualTo(newPath);
-    fileCodeOwnerStatusInfoSubject2
-        .hasNewPathStatusThat()
-        .value()
-        .hasStatusThat()
-        .isEqualTo(CodeOwnerStatus.PENDING);
+    assertThat(codeOwnerStatus)
+        .hasFileCodeOwnerStatusesThat()
+        .comparingElementsUsing(isFileCodeOwnerStatus())
+        .containsExactly(
+            FileCodeOwnerStatus.deletion(oldPath, CodeOwnerStatus.PENDING),
+            FileCodeOwnerStatus.addition(newPath, CodeOwnerStatus.PENDING));
   }
 
   @Test
@@ -160,14 +117,10 @@
     String changeId = createChange("Change Adding A File", path, "file content").getChangeId();
     CodeOwnerStatusInfo codeOwnerStatus =
         changeCodeOwnersApiFactory.change(changeId).getCodeOwnerStatus();
-    FileCodeOwnerStatusInfoSubject fileCodeOwnerStatusInfoSubject =
-        assertThat(codeOwnerStatus).hasFileCodeOwnerStatusesThat().onlyElement();
-    fileCodeOwnerStatusInfoSubject.hasChangeTypeThat().isEqualTo(ChangeType.ADDED);
-    fileCodeOwnerStatusInfoSubject.hasNewPathStatusThat().value().hasPathThat().isEqualTo(path);
-    fileCodeOwnerStatusInfoSubject
-        .hasNewPathStatusThat()
-        .value()
-        .hasStatusThat()
-        .isEqualTo(CodeOwnerStatus.INSUFFICIENT_REVIEWERS);
+    assertThat(codeOwnerStatus)
+        .hasFileCodeOwnerStatusesThat()
+        .comparingElementsUsing(isFileCodeOwnerStatus())
+        .containsExactly(
+            FileCodeOwnerStatus.addition(path, CodeOwnerStatus.INSUFFICIENT_REVIEWERS));
   }
 }
diff --git a/javatests/com/google/gerrit/plugins/codeowners/backend/CodeOwnerApprovalCheckTest.java b/javatests/com/google/gerrit/plugins/codeowners/backend/CodeOwnerApprovalCheckTest.java
index 129b10e..76510f4 100644
--- a/javatests/com/google/gerrit/plugins/codeowners/backend/CodeOwnerApprovalCheckTest.java
+++ b/javatests/com/google/gerrit/plugins/codeowners/backend/CodeOwnerApprovalCheckTest.java
@@ -16,7 +16,6 @@
 
 import static com.google.common.truth.Truth.assertThat;
 import static com.google.gerrit.acceptance.testsuite.project.TestProjectUpdate.allowLabel;
-import static com.google.gerrit.plugins.codeowners.testing.FileCodeOwnerStatusSubject.assertThat;
 import static com.google.gerrit.plugins.codeowners.testing.FileCodeOwnerStatusSubject.assertThatCollection;
 import static com.google.gerrit.server.group.SystemGroupBackend.REGISTERED_USERS;
 import static com.google.gerrit.testing.GerritJUnit.assertThrows;
@@ -101,17 +100,9 @@
 
     ImmutableSet<FileCodeOwnerStatus> fileCodeOwnerStatuses =
         codeOwnerApprovalCheck.getFileStatusesAsSet(getChangeNotes(changeId));
-    FileCodeOwnerStatusSubject fileCodeOwnerStatusSubject =
-        assertThatCollection(fileCodeOwnerStatuses).onlyElement();
-    fileCodeOwnerStatusSubject.hasNewPathStatus().value().hasPathThat().isEqualTo(path);
-    fileCodeOwnerStatusSubject
-        .hasNewPathStatus()
-        .value()
-        .hasStatusThat()
-        .isEqualTo(CodeOwnerStatus.INSUFFICIENT_REVIEWERS);
-    fileCodeOwnerStatusSubject.hasOldPathStatus().isEmpty();
-    fileCodeOwnerStatusSubject.hasChangedFile().isNoRename();
-    fileCodeOwnerStatusSubject.hasChangedFile().isNoDeletion();
+    assertThatCollection(fileCodeOwnerStatuses)
+        .containsExactly(
+            FileCodeOwnerStatus.addition(path, CodeOwnerStatus.INSUFFICIENT_REVIEWERS));
   }
 
   @Test
@@ -133,17 +124,9 @@
 
     ImmutableSet<FileCodeOwnerStatus> fileCodeOwnerStatuses =
         codeOwnerApprovalCheck.getFileStatusesAsSet(getChangeNotes(changeId));
-    FileCodeOwnerStatusSubject fileCodeOwnerStatusSubject =
-        assertThatCollection(fileCodeOwnerStatuses).onlyElement();
-    fileCodeOwnerStatusSubject.hasNewPathStatus().value().hasPathThat().isEqualTo(path);
-    fileCodeOwnerStatusSubject
-        .hasNewPathStatus()
-        .value()
-        .hasStatusThat()
-        .isEqualTo(CodeOwnerStatus.INSUFFICIENT_REVIEWERS);
-    fileCodeOwnerStatusSubject.hasOldPathStatus().isEmpty();
-    fileCodeOwnerStatusSubject.hasChangedFile().isNoRename();
-    fileCodeOwnerStatusSubject.hasChangedFile().isNoDeletion();
+    assertThatCollection(fileCodeOwnerStatuses)
+        .containsExactly(
+            FileCodeOwnerStatus.modification(path, CodeOwnerStatus.INSUFFICIENT_REVIEWERS));
   }
 
   @Test
@@ -162,17 +145,9 @@
 
     ImmutableSet<FileCodeOwnerStatus> fileCodeOwnerStatuses =
         codeOwnerApprovalCheck.getFileStatusesAsSet(getChangeNotes(changeId));
-    FileCodeOwnerStatusSubject fileCodeOwnerStatusSubject =
-        assertThatCollection(fileCodeOwnerStatuses).onlyElement();
-    fileCodeOwnerStatusSubject.hasNewPathStatus().isEmpty();
-    fileCodeOwnerStatusSubject.hasOldPathStatus().value().hasPathThat().isEqualTo(path);
-    fileCodeOwnerStatusSubject
-        .hasOldPathStatus()
-        .value()
-        .hasStatusThat()
-        .isEqualTo(CodeOwnerStatus.INSUFFICIENT_REVIEWERS);
-    fileCodeOwnerStatusSubject.hasChangedFile().isNoRename();
-    fileCodeOwnerStatusSubject.hasChangedFile().isDeletion();
+    assertThatCollection(fileCodeOwnerStatuses)
+        .containsExactly(
+            FileCodeOwnerStatus.deletion(path, CodeOwnerStatus.INSUFFICIENT_REVIEWERS));
   }
 
   @Test
@@ -192,27 +167,10 @@
 
     ImmutableSet<FileCodeOwnerStatus> fileCodeOwnerStatuses =
         codeOwnerApprovalCheck.getFileStatusesAsSet(getChangeNotes(changeId));
-    assertThatCollection(fileCodeOwnerStatuses).hasSize(2);
-    FileCodeOwnerStatusSubject fileCodeOwnerStatusSubject1 =
-        assertThatCollection(fileCodeOwnerStatuses).element(0);
-    fileCodeOwnerStatusSubject1.hasNewPathStatus().value().hasPathThat().isEqualTo(newPath);
-    fileCodeOwnerStatusSubject1
-        .hasNewPathStatus()
-        .value()
-        .hasStatusThat()
-        .isEqualTo(CodeOwnerStatus.INSUFFICIENT_REVIEWERS);
-    fileCodeOwnerStatusSubject1.hasChangedFile().isNoRename();
-    fileCodeOwnerStatusSubject1.hasChangedFile().isNoDeletion();
-    FileCodeOwnerStatusSubject fileCodeOwnerStatusSubject2 =
-        assertThatCollection(fileCodeOwnerStatuses).element(1);
-    fileCodeOwnerStatusSubject2.hasOldPathStatus().value().hasPathThat().isEqualTo(oldPath);
-    fileCodeOwnerStatusSubject2
-        .hasOldPathStatus()
-        .value()
-        .hasStatusThat()
-        .isEqualTo(CodeOwnerStatus.INSUFFICIENT_REVIEWERS);
-    fileCodeOwnerStatusSubject2.hasChangedFile().isNoRename();
-    fileCodeOwnerStatusSubject2.hasChangedFile().isDeletion();
+    assertThatCollection(fileCodeOwnerStatuses)
+        .containsExactly(
+            FileCodeOwnerStatus.deletion(oldPath, CodeOwnerStatus.INSUFFICIENT_REVIEWERS),
+            FileCodeOwnerStatus.addition(newPath, CodeOwnerStatus.INSUFFICIENT_REVIEWERS));
   }
 
   @Test
@@ -234,17 +192,8 @@
 
     ImmutableSet<FileCodeOwnerStatus> fileCodeOwnerStatuses =
         codeOwnerApprovalCheck.getFileStatusesAsSet(getChangeNotes(changeId));
-    FileCodeOwnerStatusSubject fileCodeOwnerStatusSubject =
-        assertThatCollection(fileCodeOwnerStatuses).onlyElement();
-    fileCodeOwnerStatusSubject.hasNewPathStatus().value().hasPathThat().isEqualTo(path);
-    fileCodeOwnerStatusSubject
-        .hasNewPathStatus()
-        .value()
-        .hasStatusThat()
-        .isEqualTo(CodeOwnerStatus.PENDING);
-    fileCodeOwnerStatusSubject.hasOldPathStatus().isEmpty();
-    fileCodeOwnerStatusSubject.hasChangedFile().isNoRename();
-    fileCodeOwnerStatusSubject.hasChangedFile().isNoDeletion();
+    assertThatCollection(fileCodeOwnerStatuses)
+        .containsExactly(FileCodeOwnerStatus.addition(path, CodeOwnerStatus.PENDING));
   }
 
   @Test
@@ -268,17 +217,8 @@
 
     ImmutableSet<FileCodeOwnerStatus> fileCodeOwnerStatuses =
         codeOwnerApprovalCheck.getFileStatusesAsSet(getChangeNotes(changeId));
-    FileCodeOwnerStatusSubject fileCodeOwnerStatusSubject =
-        assertThatCollection(fileCodeOwnerStatuses).onlyElement();
-    fileCodeOwnerStatusSubject.hasNewPathStatus().value().hasPathThat().isEqualTo(path);
-    fileCodeOwnerStatusSubject
-        .hasNewPathStatus()
-        .value()
-        .hasStatusThat()
-        .isEqualTo(CodeOwnerStatus.PENDING);
-    fileCodeOwnerStatusSubject.hasOldPathStatus().isEmpty();
-    fileCodeOwnerStatusSubject.hasChangedFile().isNoRename();
-    fileCodeOwnerStatusSubject.hasChangedFile().isNoDeletion();
+    assertThatCollection(fileCodeOwnerStatuses)
+        .containsExactly(FileCodeOwnerStatus.modification(path, CodeOwnerStatus.PENDING));
   }
 
   @Test
@@ -299,17 +239,8 @@
 
     ImmutableSet<FileCodeOwnerStatus> fileCodeOwnerStatuses =
         codeOwnerApprovalCheck.getFileStatusesAsSet(getChangeNotes(changeId));
-    FileCodeOwnerStatusSubject fileCodeOwnerStatusSubject =
-        assertThatCollection(fileCodeOwnerStatuses).onlyElement();
-    fileCodeOwnerStatusSubject.hasNewPathStatus().isEmpty();
-    fileCodeOwnerStatusSubject.hasOldPathStatus().value().hasPathThat().isEqualTo(path);
-    fileCodeOwnerStatusSubject
-        .hasOldPathStatus()
-        .value()
-        .hasStatusThat()
-        .isEqualTo(CodeOwnerStatus.PENDING);
-    fileCodeOwnerStatusSubject.hasChangedFile().isNoRename();
-    fileCodeOwnerStatusSubject.hasChangedFile().isDeletion();
+    assertThatCollection(fileCodeOwnerStatuses)
+        .containsExactly(FileCodeOwnerStatus.deletion(path, CodeOwnerStatus.PENDING));
   }
 
   @Test
@@ -331,27 +262,10 @@
 
     ImmutableSet<FileCodeOwnerStatus> fileCodeOwnerStatuses =
         codeOwnerApprovalCheck.getFileStatusesAsSet(getChangeNotes(changeId));
-    assertThatCollection(fileCodeOwnerStatuses).hasSize(2);
-    FileCodeOwnerStatusSubject fileCodeOwnerStatusSubject1 =
-        assertThatCollection(fileCodeOwnerStatuses).element(0);
-    fileCodeOwnerStatusSubject1.hasOldPathStatus().value().hasPathThat().isEqualTo(oldPath);
-    fileCodeOwnerStatusSubject1
-        .hasOldPathStatus()
-        .value()
-        .hasStatusThat()
-        .isEqualTo(CodeOwnerStatus.PENDING);
-    fileCodeOwnerStatusSubject1.hasChangedFile().isNoRename();
-    fileCodeOwnerStatusSubject1.hasChangedFile().isDeletion();
-    FileCodeOwnerStatusSubject fileCodeOwnerStatusSubject2 =
-        assertThatCollection(fileCodeOwnerStatuses).element(1);
-    fileCodeOwnerStatusSubject2.hasNewPathStatus().value().hasPathThat().isEqualTo(newPath);
-    fileCodeOwnerStatusSubject2
-        .hasNewPathStatus()
-        .value()
-        .hasStatusThat()
-        .isEqualTo(CodeOwnerStatus.INSUFFICIENT_REVIEWERS);
-    fileCodeOwnerStatusSubject2.hasChangedFile().isNoRename();
-    fileCodeOwnerStatusSubject2.hasChangedFile().isNoDeletion();
+    assertThatCollection(fileCodeOwnerStatuses)
+        .containsExactly(
+            FileCodeOwnerStatus.deletion(oldPath, CodeOwnerStatus.PENDING),
+            FileCodeOwnerStatus.addition(newPath, CodeOwnerStatus.INSUFFICIENT_REVIEWERS));
   }
 
   @Test
@@ -373,27 +287,10 @@
 
     ImmutableSet<FileCodeOwnerStatus> fileCodeOwnerStatuses =
         codeOwnerApprovalCheck.getFileStatusesAsSet(getChangeNotes(changeId));
-    assertThatCollection(fileCodeOwnerStatuses).hasSize(2);
-    FileCodeOwnerStatusSubject fileCodeOwnerStatusSubject1 =
-        assertThatCollection(fileCodeOwnerStatuses).element(0);
-    fileCodeOwnerStatusSubject1.hasOldPathStatus().value().hasPathThat().isEqualTo(oldPath);
-    fileCodeOwnerStatusSubject1
-        .hasOldPathStatus()
-        .value()
-        .hasStatusThat()
-        .isEqualTo(CodeOwnerStatus.INSUFFICIENT_REVIEWERS);
-    fileCodeOwnerStatusSubject1.hasChangedFile().isNoRename();
-    fileCodeOwnerStatusSubject1.hasChangedFile().isDeletion();
-    FileCodeOwnerStatusSubject fileCodeOwnerStatusSubject2 =
-        assertThatCollection(fileCodeOwnerStatuses).element(1);
-    fileCodeOwnerStatusSubject2.hasNewPathStatus().value().hasPathThat().isEqualTo(newPath);
-    fileCodeOwnerStatusSubject2
-        .hasNewPathStatus()
-        .value()
-        .hasStatusThat()
-        .isEqualTo(CodeOwnerStatus.PENDING);
-    fileCodeOwnerStatusSubject2.hasChangedFile().isNoRename();
-    fileCodeOwnerStatusSubject2.hasChangedFile().isNoDeletion();
+    assertThatCollection(fileCodeOwnerStatuses)
+        .containsExactly(
+            FileCodeOwnerStatus.deletion(oldPath, CodeOwnerStatus.INSUFFICIENT_REVIEWERS),
+            FileCodeOwnerStatus.addition(newPath, CodeOwnerStatus.PENDING));
   }
 
   @Test
@@ -410,17 +307,8 @@
 
     ImmutableSet<FileCodeOwnerStatus> fileCodeOwnerStatuses =
         codeOwnerApprovalCheck.getFileStatusesAsSet(getChangeNotes(changeId));
-    FileCodeOwnerStatusSubject fileCodeOwnerStatusSubject =
-        assertThatCollection(fileCodeOwnerStatuses).onlyElement();
-    fileCodeOwnerStatusSubject.hasNewPathStatus().value().hasPathThat().isEqualTo(path);
-    fileCodeOwnerStatusSubject
-        .hasNewPathStatus()
-        .value()
-        .hasStatusThat()
-        .isEqualTo(CodeOwnerStatus.APPROVED);
-    fileCodeOwnerStatusSubject.hasOldPathStatus().isEmpty();
-    fileCodeOwnerStatusSubject.hasChangedFile().isNoRename();
-    fileCodeOwnerStatusSubject.hasChangedFile().isNoDeletion();
+    assertThatCollection(fileCodeOwnerStatuses)
+        .containsExactly(FileCodeOwnerStatus.addition(path, CodeOwnerStatus.APPROVED));
   }
 
   @Test
@@ -439,17 +327,8 @@
 
     ImmutableSet<FileCodeOwnerStatus> fileCodeOwnerStatuses =
         codeOwnerApprovalCheck.getFileStatusesAsSet(getChangeNotes(changeId));
-    FileCodeOwnerStatusSubject fileCodeOwnerStatusSubject =
-        assertThatCollection(fileCodeOwnerStatuses).onlyElement();
-    fileCodeOwnerStatusSubject.hasNewPathStatus().value().hasPathThat().isEqualTo(path);
-    fileCodeOwnerStatusSubject
-        .hasNewPathStatus()
-        .value()
-        .hasStatusThat()
-        .isEqualTo(CodeOwnerStatus.APPROVED);
-    fileCodeOwnerStatusSubject.hasOldPathStatus().isEmpty();
-    fileCodeOwnerStatusSubject.hasChangedFile().isNoRename();
-    fileCodeOwnerStatusSubject.hasChangedFile().isNoDeletion();
+    assertThatCollection(fileCodeOwnerStatuses)
+        .containsExactly(FileCodeOwnerStatus.modification(path, CodeOwnerStatus.APPROVED));
   }
 
   @Test
@@ -465,17 +344,8 @@
 
     ImmutableSet<FileCodeOwnerStatus> fileCodeOwnerStatuses =
         codeOwnerApprovalCheck.getFileStatusesAsSet(getChangeNotes(changeId));
-    FileCodeOwnerStatusSubject fileCodeOwnerStatusSubject =
-        assertThatCollection(fileCodeOwnerStatuses).onlyElement();
-    fileCodeOwnerStatusSubject.hasNewPathStatus().isEmpty();
-    fileCodeOwnerStatusSubject.hasOldPathStatus().value().hasPathThat().isEqualTo(path);
-    fileCodeOwnerStatusSubject
-        .hasOldPathStatus()
-        .value()
-        .hasStatusThat()
-        .isEqualTo(CodeOwnerStatus.APPROVED);
-    fileCodeOwnerStatusSubject.hasChangedFile().isNoRename();
-    fileCodeOwnerStatusSubject.hasChangedFile().isDeletion();
+    assertThatCollection(fileCodeOwnerStatuses)
+        .containsExactly(FileCodeOwnerStatus.deletion(path, CodeOwnerStatus.APPROVED));
   }
 
   @Test
@@ -493,27 +363,10 @@
 
     ImmutableSet<FileCodeOwnerStatus> fileCodeOwnerStatuses =
         codeOwnerApprovalCheck.getFileStatusesAsSet(getChangeNotes(changeId));
-    assertThatCollection(fileCodeOwnerStatuses).hasSize(2);
-    FileCodeOwnerStatusSubject fileCodeOwnerStatusSubject1 =
-        assertThatCollection(fileCodeOwnerStatuses).element(0);
-    fileCodeOwnerStatusSubject1.hasOldPathStatus().value().hasPathThat().isEqualTo(oldPath);
-    fileCodeOwnerStatusSubject1
-        .hasOldPathStatus()
-        .value()
-        .hasStatusThat()
-        .isEqualTo(CodeOwnerStatus.APPROVED);
-    fileCodeOwnerStatusSubject1.hasChangedFile().isNoRename();
-    fileCodeOwnerStatusSubject1.hasChangedFile().isDeletion();
-    FileCodeOwnerStatusSubject fileCodeOwnerStatusSubject2 =
-        assertThatCollection(fileCodeOwnerStatuses).element(1);
-    fileCodeOwnerStatusSubject2.hasNewPathStatus().value().hasPathThat().isEqualTo(newPath);
-    fileCodeOwnerStatusSubject2
-        .hasNewPathStatus()
-        .value()
-        .hasStatusThat()
-        .isEqualTo(CodeOwnerStatus.INSUFFICIENT_REVIEWERS);
-    fileCodeOwnerStatusSubject2.hasChangedFile().isNoRename();
-    fileCodeOwnerStatusSubject2.hasChangedFile().isNoDeletion();
+    assertThatCollection(fileCodeOwnerStatuses)
+        .containsExactly(
+            FileCodeOwnerStatus.deletion(oldPath, CodeOwnerStatus.APPROVED),
+            FileCodeOwnerStatus.addition(newPath, CodeOwnerStatus.INSUFFICIENT_REVIEWERS));
   }
 
   @Test
@@ -531,27 +384,10 @@
 
     ImmutableSet<FileCodeOwnerStatus> fileCodeOwnerStatuses =
         codeOwnerApprovalCheck.getFileStatusesAsSet(getChangeNotes(changeId));
-    assertThatCollection(fileCodeOwnerStatuses).hasSize(2);
-    FileCodeOwnerStatusSubject fileCodeOwnerStatusSubject1 =
-        assertThatCollection(fileCodeOwnerStatuses).element(0);
-    fileCodeOwnerStatusSubject1.hasOldPathStatus().value().hasPathThat().isEqualTo(oldPath);
-    fileCodeOwnerStatusSubject1
-        .hasOldPathStatus()
-        .value()
-        .hasStatusThat()
-        .isEqualTo(CodeOwnerStatus.INSUFFICIENT_REVIEWERS);
-    fileCodeOwnerStatusSubject1.hasChangedFile().isNoRename();
-    fileCodeOwnerStatusSubject1.hasChangedFile().isDeletion();
-    FileCodeOwnerStatusSubject fileCodeOwnerStatusSubject2 =
-        assertThatCollection(fileCodeOwnerStatuses).element(1);
-    fileCodeOwnerStatusSubject2.hasNewPathStatus().value().hasPathThat().isEqualTo(newPath);
-    fileCodeOwnerStatusSubject2
-        .hasNewPathStatus()
-        .value()
-        .hasStatusThat()
-        .isEqualTo(CodeOwnerStatus.APPROVED);
-    fileCodeOwnerStatusSubject2.hasChangedFile().isNoRename();
-    fileCodeOwnerStatusSubject2.hasChangedFile().isNoDeletion();
+    assertThatCollection(fileCodeOwnerStatuses)
+        .containsExactly(
+            FileCodeOwnerStatus.deletion(oldPath, CodeOwnerStatus.INSUFFICIENT_REVIEWERS),
+            FileCodeOwnerStatus.addition(newPath, CodeOwnerStatus.APPROVED));
   }
 
   @Test
@@ -578,20 +414,13 @@
 
     ImmutableSet<FileCodeOwnerStatus> fileCodeOwnerStatuses =
         codeOwnerApprovalCheck.getFileStatusesAsSet(getChangeNotes(changeId));
-    FileCodeOwnerStatusSubject fileCodeOwnerStatusSubject =
-        assertThatCollection(fileCodeOwnerStatuses).onlyElement();
-    fileCodeOwnerStatusSubject.hasNewPathStatus().value().hasPathThat().isEqualTo(path);
-    fileCodeOwnerStatusSubject
-        .hasNewPathStatus()
-        .value()
-        .hasStatusThat()
-        .isEqualTo(
-            implicitApprovalsEnabled
-                ? CodeOwnerStatus.APPROVED
-                : CodeOwnerStatus.INSUFFICIENT_REVIEWERS);
-    fileCodeOwnerStatusSubject.hasOldPathStatus().isEmpty();
-    fileCodeOwnerStatusSubject.hasChangedFile().isNoRename();
-    fileCodeOwnerStatusSubject.hasChangedFile().isNoDeletion();
+    assertThatCollection(fileCodeOwnerStatuses)
+        .containsExactly(
+            FileCodeOwnerStatus.addition(
+                path,
+                implicitApprovalsEnabled
+                    ? CodeOwnerStatus.APPROVED
+                    : CodeOwnerStatus.INSUFFICIENT_REVIEWERS));
   }
 
   @Test
@@ -621,20 +450,13 @@
 
     ImmutableSet<FileCodeOwnerStatus> fileCodeOwnerStatuses =
         codeOwnerApprovalCheck.getFileStatusesAsSet(getChangeNotes(changeId));
-    FileCodeOwnerStatusSubject fileCodeOwnerStatusSubject =
-        assertThatCollection(fileCodeOwnerStatuses).onlyElement();
-    fileCodeOwnerStatusSubject.hasNewPathStatus().value().hasPathThat().isEqualTo(path);
-    fileCodeOwnerStatusSubject
-        .hasNewPathStatus()
-        .value()
-        .hasStatusThat()
-        .isEqualTo(
-            implicitApprovalsEnabled
-                ? CodeOwnerStatus.APPROVED
-                : CodeOwnerStatus.INSUFFICIENT_REVIEWERS);
-    fileCodeOwnerStatusSubject.hasOldPathStatus().isEmpty();
-    fileCodeOwnerStatusSubject.hasChangedFile().isNoRename();
-    fileCodeOwnerStatusSubject.hasChangedFile().isNoDeletion();
+    assertThatCollection(fileCodeOwnerStatuses)
+        .containsExactly(
+            FileCodeOwnerStatus.modification(
+                path,
+                implicitApprovalsEnabled
+                    ? CodeOwnerStatus.APPROVED
+                    : CodeOwnerStatus.INSUFFICIENT_REVIEWERS));
   }
 
   @Test
@@ -660,20 +482,13 @@
 
     ImmutableSet<FileCodeOwnerStatus> fileCodeOwnerStatuses =
         codeOwnerApprovalCheck.getFileStatusesAsSet(getChangeNotes(changeId));
-    FileCodeOwnerStatusSubject fileCodeOwnerStatusSubject =
-        assertThatCollection(fileCodeOwnerStatuses).onlyElement();
-    fileCodeOwnerStatusSubject.hasNewPathStatus().isEmpty();
-    fileCodeOwnerStatusSubject.hasOldPathStatus().value().hasPathThat().isEqualTo(path);
-    fileCodeOwnerStatusSubject
-        .hasOldPathStatus()
-        .value()
-        .hasStatusThat()
-        .isEqualTo(
-            implicitApprovalsEnabled
-                ? CodeOwnerStatus.APPROVED
-                : CodeOwnerStatus.INSUFFICIENT_REVIEWERS);
-    fileCodeOwnerStatusSubject.hasChangedFile().isNoRename();
-    fileCodeOwnerStatusSubject.hasChangedFile().isDeletion();
+    assertThatCollection(fileCodeOwnerStatuses)
+        .containsExactly(
+            FileCodeOwnerStatus.deletion(
+                path,
+                implicitApprovalsEnabled
+                    ? CodeOwnerStatus.APPROVED
+                    : CodeOwnerStatus.INSUFFICIENT_REVIEWERS));
   }
 
   @Test
@@ -702,30 +517,14 @@
 
     ImmutableSet<FileCodeOwnerStatus> fileCodeOwnerStatuses =
         codeOwnerApprovalCheck.getFileStatusesAsSet(getChangeNotes(changeId));
-    assertThatCollection(fileCodeOwnerStatuses).hasSize(2);
-    FileCodeOwnerStatusSubject fileCodeOwnerStatusSubject1 =
-        assertThatCollection(fileCodeOwnerStatuses).element(0);
-    fileCodeOwnerStatusSubject1.hasOldPathStatus().value().hasPathThat().isEqualTo(oldPath);
-    fileCodeOwnerStatusSubject1
-        .hasOldPathStatus()
-        .value()
-        .hasStatusThat()
-        .isEqualTo(
-            implicitApprovalsEnabled
-                ? CodeOwnerStatus.APPROVED
-                : CodeOwnerStatus.INSUFFICIENT_REVIEWERS);
-    fileCodeOwnerStatusSubject1.hasChangedFile().isNoRename();
-    fileCodeOwnerStatusSubject1.hasChangedFile().isDeletion();
-    FileCodeOwnerStatusSubject fileCodeOwnerStatusSubject2 =
-        assertThatCollection(fileCodeOwnerStatuses).element(1);
-    fileCodeOwnerStatusSubject2.hasNewPathStatus().value().hasPathThat().isEqualTo(newPath);
-    fileCodeOwnerStatusSubject2
-        .hasNewPathStatus()
-        .value()
-        .hasStatusThat()
-        .isEqualTo(CodeOwnerStatus.INSUFFICIENT_REVIEWERS);
-    fileCodeOwnerStatusSubject2.hasChangedFile().isNoRename();
-    fileCodeOwnerStatusSubject2.hasChangedFile().isNoDeletion();
+    assertThatCollection(fileCodeOwnerStatuses)
+        .containsExactly(
+            FileCodeOwnerStatus.deletion(
+                oldPath,
+                implicitApprovalsEnabled
+                    ? CodeOwnerStatus.APPROVED
+                    : CodeOwnerStatus.INSUFFICIENT_REVIEWERS),
+            FileCodeOwnerStatus.addition(newPath, CodeOwnerStatus.INSUFFICIENT_REVIEWERS));
   }
 
   @Test
@@ -754,30 +553,14 @@
 
     ImmutableSet<FileCodeOwnerStatus> fileCodeOwnerStatuses =
         codeOwnerApprovalCheck.getFileStatusesAsSet(getChangeNotes(changeId));
-    assertThatCollection(fileCodeOwnerStatuses).hasSize(2);
-    FileCodeOwnerStatusSubject fileCodeOwnerStatusSubject1 =
-        assertThatCollection(fileCodeOwnerStatuses).element(0);
-    fileCodeOwnerStatusSubject1.hasOldPathStatus().value().hasPathThat().isEqualTo(oldPath);
-    fileCodeOwnerStatusSubject1
-        .hasOldPathStatus()
-        .value()
-        .hasStatusThat()
-        .isEqualTo(CodeOwnerStatus.INSUFFICIENT_REVIEWERS);
-    fileCodeOwnerStatusSubject1.hasChangedFile().isNoRename();
-    fileCodeOwnerStatusSubject1.hasChangedFile().isDeletion();
-    FileCodeOwnerStatusSubject fileCodeOwnerStatusSubject2 =
-        assertThatCollection(fileCodeOwnerStatuses).element(1);
-    fileCodeOwnerStatusSubject2.hasNewPathStatus().value().hasPathThat().isEqualTo(newPath);
-    fileCodeOwnerStatusSubject2
-        .hasNewPathStatus()
-        .value()
-        .hasStatusThat()
-        .isEqualTo(
-            implicitApprovalsEnabled
-                ? CodeOwnerStatus.APPROVED
-                : CodeOwnerStatus.INSUFFICIENT_REVIEWERS);
-    fileCodeOwnerStatusSubject2.hasChangedFile().isNoRename();
-    fileCodeOwnerStatusSubject2.hasChangedFile().isNoDeletion();
+    assertThatCollection(fileCodeOwnerStatuses)
+        .containsExactly(
+            FileCodeOwnerStatus.deletion(oldPath, CodeOwnerStatus.INSUFFICIENT_REVIEWERS),
+            FileCodeOwnerStatus.addition(
+                newPath,
+                implicitApprovalsEnabled
+                    ? CodeOwnerStatus.APPROVED
+                    : CodeOwnerStatus.INSUFFICIENT_REVIEWERS));
   }
 
   @Test
@@ -792,17 +575,9 @@
 
     ImmutableSet<FileCodeOwnerStatus> fileCodeOwnerStatuses =
         codeOwnerApprovalCheck.getFileStatusesAsSet(getChangeNotes(changeId));
-    FileCodeOwnerStatusSubject fileCodeOwnerStatusSubject =
-        assertThatCollection(fileCodeOwnerStatuses).onlyElement();
-    fileCodeOwnerStatusSubject.hasNewPathStatus().value().hasPathThat().isEqualTo(path);
-    fileCodeOwnerStatusSubject
-        .hasNewPathStatus()
-        .value()
-        .hasStatusThat()
-        .isEqualTo(CodeOwnerStatus.INSUFFICIENT_REVIEWERS);
-    fileCodeOwnerStatusSubject.hasOldPathStatus().isEmpty();
-    fileCodeOwnerStatusSubject.hasChangedFile().isNoRename();
-    fileCodeOwnerStatusSubject.hasChangedFile().isNoDeletion();
+    assertThatCollection(fileCodeOwnerStatuses)
+        .containsExactly(
+            FileCodeOwnerStatus.addition(path, CodeOwnerStatus.INSUFFICIENT_REVIEWERS));
   }
 
   @Test
@@ -821,17 +596,9 @@
 
     ImmutableSet<FileCodeOwnerStatus> fileCodeOwnerStatuses =
         codeOwnerApprovalCheck.getFileStatusesAsSet(getChangeNotes(changeId));
-    FileCodeOwnerStatusSubject fileCodeOwnerStatusSubject =
-        assertThatCollection(fileCodeOwnerStatuses).onlyElement();
-    fileCodeOwnerStatusSubject.hasNewPathStatus().value().hasPathThat().isEqualTo(path);
-    fileCodeOwnerStatusSubject
-        .hasNewPathStatus()
-        .value()
-        .hasStatusThat()
-        .isEqualTo(CodeOwnerStatus.INSUFFICIENT_REVIEWERS);
-    fileCodeOwnerStatusSubject.hasOldPathStatus().isEmpty();
-    fileCodeOwnerStatusSubject.hasChangedFile().isNoRename();
-    fileCodeOwnerStatusSubject.hasChangedFile().isNoDeletion();
+    assertThatCollection(fileCodeOwnerStatuses)
+        .containsExactly(
+            FileCodeOwnerStatus.addition(path, CodeOwnerStatus.INSUFFICIENT_REVIEWERS));
   }
 
   @Test
@@ -855,14 +622,9 @@
     // implicit approvals are disabled).
     ImmutableSet<FileCodeOwnerStatus> fileCodeOwnerStatuses =
         codeOwnerApprovalCheck.getFileStatusesAsSet(getChangeNotes(changeId));
-    FileCodeOwnerStatusSubject fileCodeOwnerStatusSubject =
-        assertThatCollection(fileCodeOwnerStatuses).onlyElement();
-    fileCodeOwnerStatusSubject.hasNewPathStatus().value().hasPathThat().isEqualTo(path);
-    fileCodeOwnerStatusSubject
-        .hasNewPathStatus()
-        .value()
-        .hasStatusThat()
-        .isEqualTo(CodeOwnerStatus.INSUFFICIENT_REVIEWERS);
+    assertThatCollection(fileCodeOwnerStatuses)
+        .containsExactly(
+            FileCodeOwnerStatus.addition(path, CodeOwnerStatus.INSUFFICIENT_REVIEWERS));
 
     // Add an approval by a user that is a code owner only through the global code ownership.
     approve(changeId);
@@ -870,13 +632,8 @@
     // Check that the file is approved now.
     requestScopeOperations.setApiUser(admin.id());
     fileCodeOwnerStatuses = codeOwnerApprovalCheck.getFileStatusesAsSet(getChangeNotes(changeId));
-    fileCodeOwnerStatusSubject = assertThatCollection(fileCodeOwnerStatuses).onlyElement();
-    fileCodeOwnerStatusSubject.hasNewPathStatus().value().hasPathThat().isEqualTo(path);
-    fileCodeOwnerStatusSubject
-        .hasNewPathStatus()
-        .value()
-        .hasStatusThat()
-        .isEqualTo(CodeOwnerStatus.APPROVED);
+    assertThatCollection(fileCodeOwnerStatuses)
+        .containsExactly(FileCodeOwnerStatus.addition(path, CodeOwnerStatus.APPROVED));
   }
 
   @Test
@@ -908,17 +665,13 @@
 
     ImmutableSet<FileCodeOwnerStatus> fileCodeOwnerStatuses =
         codeOwnerApprovalCheck.getFileStatusesAsSet(getChangeNotes(changeId));
-    FileCodeOwnerStatusSubject fileCodeOwnerStatusSubject =
-        assertThatCollection(fileCodeOwnerStatuses).onlyElement();
-    fileCodeOwnerStatusSubject.hasNewPathStatus().value().hasPathThat().isEqualTo(path);
-    fileCodeOwnerStatusSubject
-        .hasNewPathStatus()
-        .value()
-        .hasStatusThat()
-        .isEqualTo(
-            implicitApprovalsEnabled
-                ? CodeOwnerStatus.APPROVED
-                : CodeOwnerStatus.INSUFFICIENT_REVIEWERS);
+    assertThatCollection(fileCodeOwnerStatuses)
+        .containsExactly(
+            FileCodeOwnerStatus.addition(
+                path,
+                implicitApprovalsEnabled
+                    ? CodeOwnerStatus.APPROVED
+                    : CodeOwnerStatus.INSUFFICIENT_REVIEWERS));
   }
 
   @Test
@@ -941,27 +694,17 @@
     // approval by default).
     ImmutableSet<FileCodeOwnerStatus> fileCodeOwnerStatuses =
         codeOwnerApprovalCheck.getFileStatusesAsSet(getChangeNotes(changeId));
-    FileCodeOwnerStatusSubject fileCodeOwnerStatusSubject =
-        assertThatCollection(fileCodeOwnerStatuses).onlyElement();
-    fileCodeOwnerStatusSubject.hasNewPathStatus().value().hasPathThat().isEqualTo(path);
-    fileCodeOwnerStatusSubject
-        .hasNewPathStatus()
-        .value()
-        .hasStatusThat()
-        .isEqualTo(CodeOwnerStatus.INSUFFICIENT_REVIEWERS);
+    assertThatCollection(fileCodeOwnerStatuses)
+        .containsExactly(
+            FileCodeOwnerStatus.addition(path, CodeOwnerStatus.INSUFFICIENT_REVIEWERS));
 
     // Add a user as reviewer that is a code owner.
     gApi.changes().id(changeId).addReviewer(user.email());
 
     // Check that the status of the file is PENDING now.
     fileCodeOwnerStatuses = codeOwnerApprovalCheck.getFileStatusesAsSet(getChangeNotes(changeId));
-    fileCodeOwnerStatusSubject = assertThatCollection(fileCodeOwnerStatuses).onlyElement();
-    fileCodeOwnerStatusSubject.hasNewPathStatus().value().hasPathThat().isEqualTo(path);
-    fileCodeOwnerStatusSubject
-        .hasNewPathStatus()
-        .value()
-        .hasStatusThat()
-        .isEqualTo(CodeOwnerStatus.PENDING);
+    assertThatCollection(fileCodeOwnerStatuses)
+        .containsExactly(FileCodeOwnerStatus.addition(path, CodeOwnerStatus.PENDING));
   }
 
   @Test
@@ -980,14 +723,9 @@
     // Verify that the file is not approved yet.
     ImmutableSet<FileCodeOwnerStatus> fileCodeOwnerStatuses =
         codeOwnerApprovalCheck.getFileStatusesAsSet(getChangeNotes(changeId));
-    FileCodeOwnerStatusSubject fileCodeOwnerStatusSubject =
-        assertThatCollection(fileCodeOwnerStatuses).onlyElement();
-    fileCodeOwnerStatusSubject.hasNewPathStatus().value().hasPathThat().isEqualTo(path);
-    fileCodeOwnerStatusSubject
-        .hasNewPathStatus()
-        .value()
-        .hasStatusThat()
-        .isEqualTo(CodeOwnerStatus.INSUFFICIENT_REVIEWERS);
+    assertThatCollection(fileCodeOwnerStatuses)
+        .containsExactly(
+            FileCodeOwnerStatus.addition(path, CodeOwnerStatus.INSUFFICIENT_REVIEWERS));
 
     // Let the bot approve the change.
     projectOperations
@@ -1001,13 +739,8 @@
     // Check that the file is approved now.
     requestScopeOperations.setApiUser(admin.id());
     fileCodeOwnerStatuses = codeOwnerApprovalCheck.getFileStatusesAsSet(getChangeNotes(changeId));
-    fileCodeOwnerStatusSubject = assertThatCollection(fileCodeOwnerStatuses).onlyElement();
-    fileCodeOwnerStatusSubject.hasNewPathStatus().value().hasPathThat().isEqualTo(path);
-    fileCodeOwnerStatusSubject
-        .hasNewPathStatus()
-        .value()
-        .hasStatusThat()
-        .isEqualTo(CodeOwnerStatus.APPROVED);
+    assertThatCollection(fileCodeOwnerStatuses)
+        .containsExactly(FileCodeOwnerStatus.addition(path, CodeOwnerStatus.APPROVED));
   }
 
   @Test
@@ -1035,17 +768,13 @@
 
     ImmutableSet<FileCodeOwnerStatus> fileCodeOwnerStatuses =
         codeOwnerApprovalCheck.getFileStatusesAsSet(getChangeNotes(changeId));
-    FileCodeOwnerStatusSubject fileCodeOwnerStatusSubject =
-        assertThatCollection(fileCodeOwnerStatuses).onlyElement();
-    fileCodeOwnerStatusSubject.hasNewPathStatus().value().hasPathThat().isEqualTo(path);
-    fileCodeOwnerStatusSubject
-        .hasNewPathStatus()
-        .value()
-        .hasStatusThat()
-        .isEqualTo(
-            implicitApprovalsEnabled
-                ? CodeOwnerStatus.APPROVED
-                : CodeOwnerStatus.INSUFFICIENT_REVIEWERS);
+    assertThatCollection(fileCodeOwnerStatuses)
+        .containsExactly(
+            FileCodeOwnerStatus.addition(
+                path,
+                implicitApprovalsEnabled
+                    ? CodeOwnerStatus.APPROVED
+                    : CodeOwnerStatus.INSUFFICIENT_REVIEWERS));
   }
 
   @Test
@@ -1064,14 +793,9 @@
     // Verify that the status of the file is INSUFFICIENT_REVIEWERS.
     ImmutableSet<FileCodeOwnerStatus> fileCodeOwnerStatuses =
         codeOwnerApprovalCheck.getFileStatusesAsSet(getChangeNotes(changeId));
-    FileCodeOwnerStatusSubject fileCodeOwnerStatusSubject =
-        assertThatCollection(fileCodeOwnerStatuses).onlyElement();
-    fileCodeOwnerStatusSubject.hasNewPathStatus().value().hasPathThat().isEqualTo(path);
-    fileCodeOwnerStatusSubject
-        .hasNewPathStatus()
-        .value()
-        .hasStatusThat()
-        .isEqualTo(CodeOwnerStatus.INSUFFICIENT_REVIEWERS);
+    assertThatCollection(fileCodeOwnerStatuses)
+        .containsExactly(
+            FileCodeOwnerStatus.addition(path, CodeOwnerStatus.INSUFFICIENT_REVIEWERS));
 
     // Add the bot approve as reviewer.
     gApi.changes().id(changeId).addReviewer(bot.email());
@@ -1079,13 +803,8 @@
     // Check that the status of the file is PENDING now.
     requestScopeOperations.setApiUser(admin.id());
     fileCodeOwnerStatuses = codeOwnerApprovalCheck.getFileStatusesAsSet(getChangeNotes(changeId));
-    fileCodeOwnerStatusSubject = assertThatCollection(fileCodeOwnerStatuses).onlyElement();
-    fileCodeOwnerStatusSubject.hasNewPathStatus().value().hasPathThat().isEqualTo(path);
-    fileCodeOwnerStatusSubject
-        .hasNewPathStatus()
-        .value()
-        .hasStatusThat()
-        .isEqualTo(CodeOwnerStatus.PENDING);
+    assertThatCollection(fileCodeOwnerStatuses)
+        .containsExactly(FileCodeOwnerStatus.addition(path, CodeOwnerStatus.PENDING));
 
     // Let the bot approve the change.
     projectOperations
@@ -1099,13 +818,8 @@
     // Check that the file is approved now.
     requestScopeOperations.setApiUser(admin.id());
     fileCodeOwnerStatuses = codeOwnerApprovalCheck.getFileStatusesAsSet(getChangeNotes(changeId));
-    fileCodeOwnerStatusSubject = assertThatCollection(fileCodeOwnerStatuses).onlyElement();
-    fileCodeOwnerStatusSubject.hasNewPathStatus().value().hasPathThat().isEqualTo(path);
-    fileCodeOwnerStatusSubject
-        .hasNewPathStatus()
-        .value()
-        .hasStatusThat()
-        .isEqualTo(CodeOwnerStatus.APPROVED);
+    assertThatCollection(fileCodeOwnerStatuses)
+        .containsExactly(FileCodeOwnerStatus.addition(path, CodeOwnerStatus.APPROVED));
   }
 
   @Test
@@ -1121,14 +835,9 @@
     // implicit approvals are disabled).
     ImmutableSet<FileCodeOwnerStatus> fileCodeOwnerStatuses =
         codeOwnerApprovalCheck.getFileStatusesAsSet(getChangeNotes(changeId));
-    FileCodeOwnerStatusSubject fileCodeOwnerStatusSubject =
-        assertThatCollection(fileCodeOwnerStatuses).onlyElement();
-    fileCodeOwnerStatusSubject.hasNewPathStatus().value().hasPathThat().isEqualTo(path);
-    fileCodeOwnerStatusSubject
-        .hasNewPathStatus()
-        .value()
-        .hasStatusThat()
-        .isEqualTo(CodeOwnerStatus.INSUFFICIENT_REVIEWERS);
+    assertThatCollection(fileCodeOwnerStatuses)
+        .containsExactly(
+            FileCodeOwnerStatus.addition(path, CodeOwnerStatus.INSUFFICIENT_REVIEWERS));
 
     // Add an approval by a user that is a code owner only through the global code ownership.
     approve(changeId);
@@ -1136,13 +845,8 @@
     // Check that the file is approved now.
     requestScopeOperations.setApiUser(admin.id());
     fileCodeOwnerStatuses = codeOwnerApprovalCheck.getFileStatusesAsSet(getChangeNotes(changeId));
-    fileCodeOwnerStatusSubject = assertThatCollection(fileCodeOwnerStatuses).onlyElement();
-    fileCodeOwnerStatusSubject.hasNewPathStatus().value().hasPathThat().isEqualTo(path);
-    fileCodeOwnerStatusSubject
-        .hasNewPathStatus()
-        .value()
-        .hasStatusThat()
-        .isEqualTo(CodeOwnerStatus.APPROVED);
+    assertThatCollection(fileCodeOwnerStatuses)
+        .containsExactly(FileCodeOwnerStatus.addition(path, CodeOwnerStatus.APPROVED));
   }
 
   @Test
@@ -1169,17 +873,13 @@
 
     ImmutableSet<FileCodeOwnerStatus> fileCodeOwnerStatuses =
         codeOwnerApprovalCheck.getFileStatusesAsSet(getChangeNotes(changeId));
-    FileCodeOwnerStatusSubject fileCodeOwnerStatusSubject =
-        assertThatCollection(fileCodeOwnerStatuses).onlyElement();
-    fileCodeOwnerStatusSubject.hasNewPathStatus().value().hasPathThat().isEqualTo(path);
-    fileCodeOwnerStatusSubject
-        .hasNewPathStatus()
-        .value()
-        .hasStatusThat()
-        .isEqualTo(
-            implicitApprovalsEnabled
-                ? CodeOwnerStatus.APPROVED
-                : CodeOwnerStatus.INSUFFICIENT_REVIEWERS);
+    assertThatCollection(fileCodeOwnerStatuses)
+        .containsExactly(
+            FileCodeOwnerStatus.addition(
+                path,
+                implicitApprovalsEnabled
+                    ? CodeOwnerStatus.APPROVED
+                    : CodeOwnerStatus.INSUFFICIENT_REVIEWERS));
   }
 
   @Test
@@ -1194,27 +894,17 @@
     // approval by default).
     ImmutableSet<FileCodeOwnerStatus> fileCodeOwnerStatuses =
         codeOwnerApprovalCheck.getFileStatusesAsSet(getChangeNotes(changeId));
-    FileCodeOwnerStatusSubject fileCodeOwnerStatusSubject =
-        assertThatCollection(fileCodeOwnerStatuses).onlyElement();
-    fileCodeOwnerStatusSubject.hasNewPathStatus().value().hasPathThat().isEqualTo(path);
-    fileCodeOwnerStatusSubject
-        .hasNewPathStatus()
-        .value()
-        .hasStatusThat()
-        .isEqualTo(CodeOwnerStatus.INSUFFICIENT_REVIEWERS);
+    assertThatCollection(fileCodeOwnerStatuses)
+        .containsExactly(
+            FileCodeOwnerStatus.addition(path, CodeOwnerStatus.INSUFFICIENT_REVIEWERS));
 
     // Add a user as reviewer that is a code owner only through the global code ownership.
     gApi.changes().id(changeId).addReviewer(user.email());
 
     // Check that the status of the file is PENDING now.
     fileCodeOwnerStatuses = codeOwnerApprovalCheck.getFileStatusesAsSet(getChangeNotes(changeId));
-    fileCodeOwnerStatusSubject = assertThatCollection(fileCodeOwnerStatuses).onlyElement();
-    fileCodeOwnerStatusSubject.hasNewPathStatus().value().hasPathThat().isEqualTo(path);
-    fileCodeOwnerStatusSubject
-        .hasNewPathStatus()
-        .value()
-        .hasStatusThat()
-        .isEqualTo(CodeOwnerStatus.PENDING);
+    assertThatCollection(fileCodeOwnerStatuses)
+        .containsExactly(FileCodeOwnerStatus.addition(path, CodeOwnerStatus.PENDING));
   }
 
   @Test
@@ -1243,14 +933,8 @@
         codeOwnerApprovalCheck.getFileStatusesAsSet(getChangeNotes(changeId));
     // The expected status is APPROVED since 'user' which is configured as code owner on the root
     // level approved the change.
-    FileCodeOwnerStatusSubject fileCodeOwnerStatusSubject =
-        assertThatCollection(fileCodeOwnerStatuses).onlyElement();
-    fileCodeOwnerStatusSubject.hasNewPathStatus().value().hasPathThat().isEqualTo(path);
-    fileCodeOwnerStatusSubject
-        .hasNewPathStatus()
-        .value()
-        .hasStatusThat()
-        .isEqualTo(CodeOwnerStatus.APPROVED);
+    assertThatCollection(fileCodeOwnerStatuses)
+        .containsExactly(FileCodeOwnerStatus.addition(path, CodeOwnerStatus.APPROVED));
   }
 
   @Test
@@ -1258,6 +942,9 @@
   public void getStatus_overrideApprovesAllFiles() throws Exception {
     createOwnersOverrideLabel();
 
+    String path1 = "foo/baz.config";
+    String path2 = "bar/baz.config";
+
     // Create a change.
     String changeId =
         pushFactory
@@ -1266,33 +953,28 @@
                 testRepo,
                 "Test Change",
                 ImmutableMap.of(
-                    "foo/baz.config", "content",
-                    "bar/baz.config", "other content"))
+                    path1, "content",
+                    path2, "other content"))
             .to("refs/for/master")
             .getChangeId();
 
     // Without Owners-Override approval the expected status is INSUFFICIENT_REVIEWERS.
-    for (FileCodeOwnerStatus fileCodeOwnerStatus :
-        codeOwnerApprovalCheck.getFileStatusesAsSet(getChangeNotes(changeId))) {
-      assertThat(fileCodeOwnerStatus)
-          .hasNewPathStatus()
-          .value()
-          .hasStatusThat()
-          .isEqualTo(CodeOwnerStatus.INSUFFICIENT_REVIEWERS);
-    }
+    ImmutableSet<FileCodeOwnerStatus> fileCodeOwnerStatuses =
+        codeOwnerApprovalCheck.getFileStatusesAsSet(getChangeNotes(changeId));
+    assertThatCollection(fileCodeOwnerStatuses)
+        .containsExactly(
+            FileCodeOwnerStatus.addition(path1, CodeOwnerStatus.INSUFFICIENT_REVIEWERS),
+            FileCodeOwnerStatus.addition(path2, CodeOwnerStatus.INSUFFICIENT_REVIEWERS));
 
     // Add an override approval.
     gApi.changes().id(changeId).current().review(new ReviewInput().label("Owners-Override", 1));
 
     // With Owners-Override approval the expected status is APPROVED.
-    for (FileCodeOwnerStatus fileCodeOwnerStatus :
-        codeOwnerApprovalCheck.getFileStatusesAsSet(getChangeNotes(changeId))) {
-      assertThat(fileCodeOwnerStatus)
-          .hasNewPathStatus()
-          .value()
-          .hasStatusThat()
-          .isEqualTo(CodeOwnerStatus.APPROVED);
-    }
+    fileCodeOwnerStatuses = codeOwnerApprovalCheck.getFileStatusesAsSet(getChangeNotes(changeId));
+    assertThatCollection(fileCodeOwnerStatuses)
+        .containsExactly(
+            FileCodeOwnerStatus.addition(path1, CodeOwnerStatus.APPROVED),
+            FileCodeOwnerStatus.addition(path2, CodeOwnerStatus.APPROVED));
   }
 
   @Test
@@ -1303,6 +985,9 @@
     createOwnersOverrideLabel();
     createOwnersOverrideLabel("Another-Override");
 
+    String path1 = "foo/baz.config";
+    String path2 = "bar/baz.config";
+
     // Create a change.
     String changeId =
         pushFactory
@@ -1311,59 +996,48 @@
                 testRepo,
                 "Test Change",
                 ImmutableMap.of(
-                    "foo/baz.config", "content",
-                    "bar/baz.config", "other content"))
+                    path1, "content",
+                    path2, "other content"))
             .to("refs/for/master")
             .getChangeId();
 
     // Without override approval the expected status is INSUFFICIENT_REVIEWERS.
-    for (FileCodeOwnerStatus fileCodeOwnerStatus :
-        codeOwnerApprovalCheck.getFileStatusesAsSet(getChangeNotes(changeId))) {
-      assertThat(fileCodeOwnerStatus)
-          .hasNewPathStatus()
-          .value()
-          .hasStatusThat()
-          .isEqualTo(CodeOwnerStatus.INSUFFICIENT_REVIEWERS);
-    }
+    ImmutableSet<FileCodeOwnerStatus> fileCodeOwnerStatuses =
+        codeOwnerApprovalCheck.getFileStatusesAsSet(getChangeNotes(changeId));
+    assertThatCollection(fileCodeOwnerStatuses)
+        .containsExactly(
+            FileCodeOwnerStatus.addition(path1, CodeOwnerStatus.INSUFFICIENT_REVIEWERS),
+            FileCodeOwnerStatus.addition(path2, CodeOwnerStatus.INSUFFICIENT_REVIEWERS));
 
     // Add an override approval.
     gApi.changes().id(changeId).current().review(new ReviewInput().label("Owners-Override", 1));
 
     // With override approval the expected status is APPROVED.
-    for (FileCodeOwnerStatus fileCodeOwnerStatus :
-        codeOwnerApprovalCheck.getFileStatusesAsSet(getChangeNotes(changeId))) {
-      assertThat(fileCodeOwnerStatus)
-          .hasNewPathStatus()
-          .value()
-          .hasStatusThat()
-          .isEqualTo(CodeOwnerStatus.APPROVED);
-    }
+    fileCodeOwnerStatuses = codeOwnerApprovalCheck.getFileStatusesAsSet(getChangeNotes(changeId));
+    assertThatCollection(fileCodeOwnerStatuses)
+        .containsExactly(
+            FileCodeOwnerStatus.addition(path1, CodeOwnerStatus.APPROVED),
+            FileCodeOwnerStatus.addition(path2, CodeOwnerStatus.APPROVED));
 
     // Delete the override approval.
     gApi.changes().id(changeId).current().review(new ReviewInput().label("Owners-Override", 0));
 
     // Without override approval the expected status is INSUFFICIENT_REVIEWERS.
-    for (FileCodeOwnerStatus fileCodeOwnerStatus :
-        codeOwnerApprovalCheck.getFileStatusesAsSet(getChangeNotes(changeId))) {
-      assertThat(fileCodeOwnerStatus)
-          .hasNewPathStatus()
-          .value()
-          .hasStatusThat()
-          .isEqualTo(CodeOwnerStatus.INSUFFICIENT_REVIEWERS);
-    }
+    fileCodeOwnerStatuses = codeOwnerApprovalCheck.getFileStatusesAsSet(getChangeNotes(changeId));
+    assertThatCollection(fileCodeOwnerStatuses)
+        .containsExactly(
+            FileCodeOwnerStatus.addition(path1, CodeOwnerStatus.INSUFFICIENT_REVIEWERS),
+            FileCodeOwnerStatus.addition(path2, CodeOwnerStatus.INSUFFICIENT_REVIEWERS));
 
     // Add another override approval.
     gApi.changes().id(changeId).current().review(new ReviewInput().label("Another-Override", 1));
 
     // With override approval the expected status is APPROVED.
-    for (FileCodeOwnerStatus fileCodeOwnerStatus :
-        codeOwnerApprovalCheck.getFileStatusesAsSet(getChangeNotes(changeId))) {
-      assertThat(fileCodeOwnerStatus)
-          .hasNewPathStatus()
-          .value()
-          .hasStatusThat()
-          .isEqualTo(CodeOwnerStatus.APPROVED);
-    }
+    fileCodeOwnerStatuses = codeOwnerApprovalCheck.getFileStatusesAsSet(getChangeNotes(changeId));
+    assertThatCollection(fileCodeOwnerStatuses)
+        .containsExactly(
+            FileCodeOwnerStatus.addition(path1, CodeOwnerStatus.APPROVED),
+            FileCodeOwnerStatus.addition(path2, CodeOwnerStatus.APPROVED));
   }
 
   @Test
@@ -1514,14 +1188,9 @@
     // Verify that the file is not approved yet.
     ImmutableSet<FileCodeOwnerStatus> fileCodeOwnerStatuses =
         codeOwnerApprovalCheck.getFileStatusesAsSet(getChangeNotes(changeId));
-    FileCodeOwnerStatusSubject fileCodeOwnerStatusSubject =
-        assertThatCollection(fileCodeOwnerStatuses).onlyElement();
-    fileCodeOwnerStatusSubject.hasNewPathStatus().value().hasPathThat().isEqualTo(path);
-    fileCodeOwnerStatusSubject
-        .hasNewPathStatus()
-        .value()
-        .hasStatusThat()
-        .isEqualTo(CodeOwnerStatus.INSUFFICIENT_REVIEWERS);
+    assertThatCollection(fileCodeOwnerStatuses)
+        .containsExactly(
+            FileCodeOwnerStatus.addition(path, CodeOwnerStatus.INSUFFICIENT_REVIEWERS));
 
     // Let the 'user' approve the change.
     projectOperations
@@ -1535,13 +1204,8 @@
     // Check that the file is approved now.
     requestScopeOperations.setApiUser(admin.id());
     fileCodeOwnerStatuses = codeOwnerApprovalCheck.getFileStatusesAsSet(getChangeNotes(changeId));
-    fileCodeOwnerStatusSubject = assertThatCollection(fileCodeOwnerStatuses).onlyElement();
-    fileCodeOwnerStatusSubject.hasNewPathStatus().value().hasPathThat().isEqualTo(path);
-    fileCodeOwnerStatusSubject
-        .hasNewPathStatus()
-        .value()
-        .hasStatusThat()
-        .isEqualTo(CodeOwnerStatus.APPROVED);
+    assertThatCollection(fileCodeOwnerStatuses)
+        .containsExactly(FileCodeOwnerStatus.addition(path, CodeOwnerStatus.APPROVED));
 
     // Change some other file ('user' who uploads the change is a code owner and hence owner
     // approvals are implicit for this change)
@@ -1560,13 +1224,8 @@
 
     // Check that the file is still approved.
     fileCodeOwnerStatuses = codeOwnerApprovalCheck.getFileStatusesAsSet(getChangeNotes(changeId));
-    fileCodeOwnerStatusSubject = assertThatCollection(fileCodeOwnerStatuses).onlyElement();
-    fileCodeOwnerStatusSubject.hasNewPathStatus().value().hasPathThat().isEqualTo(path);
-    fileCodeOwnerStatusSubject
-        .hasNewPathStatus()
-        .value()
-        .hasStatusThat()
-        .isEqualTo(CodeOwnerStatus.APPROVED);
+    assertThatCollection(fileCodeOwnerStatuses)
+        .containsExactly(FileCodeOwnerStatus.addition(path, CodeOwnerStatus.APPROVED));
   }
 
   @Test
@@ -1588,14 +1247,9 @@
     // Verify that the file is not approved yet.
     ImmutableSet<FileCodeOwnerStatus> fileCodeOwnerStatuses =
         codeOwnerApprovalCheck.getFileStatusesAsSet(getChangeNotes(changeId));
-    FileCodeOwnerStatusSubject fileCodeOwnerStatusSubject =
-        assertThatCollection(fileCodeOwnerStatuses).onlyElement();
-    fileCodeOwnerStatusSubject.hasNewPathStatus().value().hasPathThat().isEqualTo(path);
-    fileCodeOwnerStatusSubject
-        .hasNewPathStatus()
-        .value()
-        .hasStatusThat()
-        .isEqualTo(CodeOwnerStatus.INSUFFICIENT_REVIEWERS);
+    assertThatCollection(fileCodeOwnerStatuses)
+        .containsExactly(
+            FileCodeOwnerStatus.addition(path, CodeOwnerStatus.INSUFFICIENT_REVIEWERS));
 
     // Apply an override
     gApi.changes().id(changeId).current().review(new ReviewInput().label("Owners-Override", 1));
@@ -1603,13 +1257,8 @@
     // Check that the file is approved now.
     requestScopeOperations.setApiUser(admin.id());
     fileCodeOwnerStatuses = codeOwnerApprovalCheck.getFileStatusesAsSet(getChangeNotes(changeId));
-    fileCodeOwnerStatusSubject = assertThatCollection(fileCodeOwnerStatuses).onlyElement();
-    fileCodeOwnerStatusSubject.hasNewPathStatus().value().hasPathThat().isEqualTo(path);
-    fileCodeOwnerStatusSubject
-        .hasNewPathStatus()
-        .value()
-        .hasStatusThat()
-        .isEqualTo(CodeOwnerStatus.APPROVED);
+    assertThatCollection(fileCodeOwnerStatuses)
+        .containsExactly(FileCodeOwnerStatus.addition(path, CodeOwnerStatus.APPROVED));
 
     // Change some other file and submit the change with an override.
     String changeId2 =
@@ -1627,13 +1276,8 @@
 
     // Check that the file is still approved.
     fileCodeOwnerStatuses = codeOwnerApprovalCheck.getFileStatusesAsSet(getChangeNotes(changeId));
-    fileCodeOwnerStatusSubject = assertThatCollection(fileCodeOwnerStatuses).onlyElement();
-    fileCodeOwnerStatusSubject.hasNewPathStatus().value().hasPathThat().isEqualTo(path);
-    fileCodeOwnerStatusSubject
-        .hasNewPathStatus()
-        .value()
-        .hasStatusThat()
-        .isEqualTo(CodeOwnerStatus.APPROVED);
+    assertThatCollection(fileCodeOwnerStatuses)
+        .containsExactly(FileCodeOwnerStatus.addition(path, CodeOwnerStatus.APPROVED));
   }
 
   @Test
@@ -1652,14 +1296,9 @@
     // Verify that the file is not approved yet.
     ImmutableSet<FileCodeOwnerStatus> fileCodeOwnerStatuses =
         codeOwnerApprovalCheck.getFileStatusesAsSet(getChangeNotes(changeId));
-    FileCodeOwnerStatusSubject fileCodeOwnerStatusSubject =
-        assertThatCollection(fileCodeOwnerStatuses).onlyElement();
-    fileCodeOwnerStatusSubject.hasNewPathStatus().value().hasPathThat().isEqualTo(path);
-    fileCodeOwnerStatusSubject
-        .hasNewPathStatus()
-        .value()
-        .hasStatusThat()
-        .isEqualTo(CodeOwnerStatus.INSUFFICIENT_REVIEWERS);
+    assertThatCollection(fileCodeOwnerStatuses)
+        .containsExactly(
+            FileCodeOwnerStatus.addition(path, CodeOwnerStatus.INSUFFICIENT_REVIEWERS));
 
     // Let 'user' approve the change (vote Code-Review+2)
     projectOperations
@@ -1673,13 +1312,8 @@
     // Check that the file is approved now.
     requestScopeOperations.setApiUser(admin.id());
     fileCodeOwnerStatuses = codeOwnerApprovalCheck.getFileStatusesAsSet(getChangeNotes(changeId));
-    fileCodeOwnerStatusSubject = assertThatCollection(fileCodeOwnerStatuses).onlyElement();
-    fileCodeOwnerStatusSubject.hasNewPathStatus().value().hasPathThat().isEqualTo(path);
-    fileCodeOwnerStatusSubject
-        .hasNewPathStatus()
-        .value()
-        .hasStatusThat()
-        .isEqualTo(CodeOwnerStatus.APPROVED);
+    assertThatCollection(fileCodeOwnerStatuses)
+        .containsExactly(FileCodeOwnerStatus.addition(path, CodeOwnerStatus.APPROVED));
   }
 
   @Test
@@ -1714,14 +1348,9 @@
     // Verify that the file is not approved yet.
     ImmutableSet<FileCodeOwnerStatus> fileCodeOwnerStatuses =
         codeOwnerApprovalCheck.getFileStatusesAsSet(getChangeNotes(changeId));
-    FileCodeOwnerStatusSubject fileCodeOwnerStatusSubject =
-        assertThatCollection(fileCodeOwnerStatuses).onlyElement();
-    fileCodeOwnerStatusSubject.hasNewPathStatus().value().hasPathThat().isEqualTo(path);
-    fileCodeOwnerStatusSubject
-        .hasNewPathStatus()
-        .value()
-        .hasStatusThat()
-        .isEqualTo(CodeOwnerStatus.INSUFFICIENT_REVIEWERS);
+    assertThatCollection(fileCodeOwnerStatuses)
+        .containsExactly(
+            FileCodeOwnerStatus.addition(path, CodeOwnerStatus.INSUFFICIENT_REVIEWERS));
 
     // Let 'user2' override with Owners-Override+2
     requestScopeOperations.setApiUser(user2.id());
@@ -1730,13 +1359,8 @@
     // Check that the file is approved now.
     requestScopeOperations.setApiUser(admin.id());
     fileCodeOwnerStatuses = codeOwnerApprovalCheck.getFileStatusesAsSet(getChangeNotes(changeId));
-    fileCodeOwnerStatusSubject = assertThatCollection(fileCodeOwnerStatuses).onlyElement();
-    fileCodeOwnerStatusSubject.hasNewPathStatus().value().hasPathThat().isEqualTo(path);
-    fileCodeOwnerStatusSubject
-        .hasNewPathStatus()
-        .value()
-        .hasStatusThat()
-        .isEqualTo(CodeOwnerStatus.APPROVED);
+    assertThatCollection(fileCodeOwnerStatuses)
+        .containsExactly(FileCodeOwnerStatus.addition(path, CodeOwnerStatus.APPROVED));
   }
 
   @Test
@@ -1754,14 +1378,9 @@
     // Verify that the file is not approved yet.
     ImmutableSet<FileCodeOwnerStatus> fileCodeOwnerStatuses =
         codeOwnerApprovalCheck.getFileStatusesAsSet(getChangeNotes(changeId));
-    FileCodeOwnerStatusSubject fileCodeOwnerStatusSubject =
-        assertThatCollection(fileCodeOwnerStatuses).onlyElement();
-    fileCodeOwnerStatusSubject.hasNewPathStatus().value().hasPathThat().isEqualTo(path);
-    fileCodeOwnerStatusSubject
-        .hasNewPathStatus()
-        .value()
-        .hasStatusThat()
-        .isEqualTo(CodeOwnerStatus.INSUFFICIENT_REVIEWERS);
+    assertThatCollection(fileCodeOwnerStatuses)
+        .containsExactly(
+            FileCodeOwnerStatus.addition(path, CodeOwnerStatus.INSUFFICIENT_REVIEWERS));
 
     // Let the project owner approve the change.
     requestScopeOperations.setApiUser(admin.id());
@@ -1769,13 +1388,9 @@
 
     // Verify that the file is not approved yet
     fileCodeOwnerStatuses = codeOwnerApprovalCheck.getFileStatusesAsSet(getChangeNotes(changeId));
-    fileCodeOwnerStatusSubject = assertThatCollection(fileCodeOwnerStatuses).onlyElement();
-    fileCodeOwnerStatusSubject.hasNewPathStatus().value().hasPathThat().isEqualTo(path);
-    fileCodeOwnerStatusSubject
-        .hasNewPathStatus()
-        .value()
-        .hasStatusThat()
-        .isEqualTo(CodeOwnerStatus.INSUFFICIENT_REVIEWERS);
+    assertThatCollection(fileCodeOwnerStatuses)
+        .containsExactly(
+            FileCodeOwnerStatus.addition(path, CodeOwnerStatus.INSUFFICIENT_REVIEWERS));
 
     // Let the code owner approve the change.
     projectOperations
@@ -1789,13 +1404,8 @@
     // Check that the file is approved now.
     requestScopeOperations.setApiUser(admin.id());
     fileCodeOwnerStatuses = codeOwnerApprovalCheck.getFileStatusesAsSet(getChangeNotes(changeId));
-    fileCodeOwnerStatusSubject = assertThatCollection(fileCodeOwnerStatuses).onlyElement();
-    fileCodeOwnerStatusSubject.hasNewPathStatus().value().hasPathThat().isEqualTo(path);
-    fileCodeOwnerStatusSubject
-        .hasNewPathStatus()
-        .value()
-        .hasStatusThat()
-        .isEqualTo(CodeOwnerStatus.APPROVED);
+    assertThatCollection(fileCodeOwnerStatuses)
+        .containsExactly(FileCodeOwnerStatus.addition(path, CodeOwnerStatus.APPROVED));
   }
 
   @Test
@@ -1813,14 +1423,9 @@
     // Verify that the file is not approved yet.
     ImmutableSet<FileCodeOwnerStatus> fileCodeOwnerStatuses =
         codeOwnerApprovalCheck.getFileStatusesAsSet(getChangeNotes(changeId));
-    FileCodeOwnerStatusSubject fileCodeOwnerStatusSubject =
-        assertThatCollection(fileCodeOwnerStatuses).onlyElement();
-    fileCodeOwnerStatusSubject.hasNewPathStatus().value().hasPathThat().isEqualTo(path);
-    fileCodeOwnerStatusSubject
-        .hasNewPathStatus()
-        .value()
-        .hasStatusThat()
-        .isEqualTo(CodeOwnerStatus.INSUFFICIENT_REVIEWERS);
+    assertThatCollection(fileCodeOwnerStatuses)
+        .containsExactly(
+            FileCodeOwnerStatus.addition(path, CodeOwnerStatus.INSUFFICIENT_REVIEWERS));
 
     // Let the code owner approve the change.
     projectOperations
@@ -1834,13 +1439,8 @@
     // Check that the file is approved now.
     requestScopeOperations.setApiUser(admin.id());
     fileCodeOwnerStatuses = codeOwnerApprovalCheck.getFileStatusesAsSet(getChangeNotes(changeId));
-    fileCodeOwnerStatusSubject = assertThatCollection(fileCodeOwnerStatuses).onlyElement();
-    fileCodeOwnerStatusSubject.hasNewPathStatus().value().hasPathThat().isEqualTo(path);
-    fileCodeOwnerStatusSubject
-        .hasNewPathStatus()
-        .value()
-        .hasStatusThat()
-        .isEqualTo(CodeOwnerStatus.APPROVED);
+    assertThatCollection(fileCodeOwnerStatuses)
+        .containsExactly(FileCodeOwnerStatus.addition(path, CodeOwnerStatus.APPROVED));
   }
 
   @Test
@@ -1868,14 +1468,13 @@
     FileCodeOwnerStatusSubject fileCodeOwnerStatusSubject =
         assertThatCollection(fileCodeOwnerStatuses).onlyElement();
     fileCodeOwnerStatusSubject.hasNewPathStatus().value().hasPathThat().isEqualTo(path);
-    fileCodeOwnerStatusSubject
-        .hasNewPathStatus()
-        .value()
-        .hasStatusThat()
-        .isEqualTo(
-            implicitApprovalsEnabled
-                ? CodeOwnerStatus.APPROVED
-                : CodeOwnerStatus.INSUFFICIENT_REVIEWERS);
+    assertThatCollection(fileCodeOwnerStatuses)
+        .containsExactly(
+            FileCodeOwnerStatus.addition(
+                path,
+                implicitApprovalsEnabled
+                    ? CodeOwnerStatus.APPROVED
+                    : CodeOwnerStatus.INSUFFICIENT_REVIEWERS));
   }
 
   @Test
@@ -1893,14 +1492,9 @@
     // Verify that the status of the file is INSUFFICIENT_REVIEWERS.
     ImmutableSet<FileCodeOwnerStatus> fileCodeOwnerStatuses =
         codeOwnerApprovalCheck.getFileStatusesAsSet(getChangeNotes(changeId));
-    FileCodeOwnerStatusSubject fileCodeOwnerStatusSubject =
-        assertThatCollection(fileCodeOwnerStatuses).onlyElement();
-    fileCodeOwnerStatusSubject.hasNewPathStatus().value().hasPathThat().isEqualTo(path);
-    fileCodeOwnerStatusSubject
-        .hasNewPathStatus()
-        .value()
-        .hasStatusThat()
-        .isEqualTo(CodeOwnerStatus.INSUFFICIENT_REVIEWERS);
+    assertThatCollection(fileCodeOwnerStatuses)
+        .containsExactly(
+            FileCodeOwnerStatus.addition(path, CodeOwnerStatus.INSUFFICIENT_REVIEWERS));
 
     // Add the default code owner as reviewer.
     gApi.changes().id(changeId).addReviewer(user.email());
@@ -1908,13 +1502,8 @@
     // Check that the status of the file is PENDING now.
     requestScopeOperations.setApiUser(admin.id());
     fileCodeOwnerStatuses = codeOwnerApprovalCheck.getFileStatusesAsSet(getChangeNotes(changeId));
-    fileCodeOwnerStatusSubject = assertThatCollection(fileCodeOwnerStatuses).onlyElement();
-    fileCodeOwnerStatusSubject.hasNewPathStatus().value().hasPathThat().isEqualTo(path);
-    fileCodeOwnerStatusSubject
-        .hasNewPathStatus()
-        .value()
-        .hasStatusThat()
-        .isEqualTo(CodeOwnerStatus.PENDING);
+    assertThatCollection(fileCodeOwnerStatuses)
+        .containsExactly(FileCodeOwnerStatus.addition(path, CodeOwnerStatus.PENDING));
 
     // Let the default code owner approve the change.
     projectOperations
@@ -1928,13 +1517,8 @@
     // Check that the file is approved now.
     requestScopeOperations.setApiUser(admin.id());
     fileCodeOwnerStatuses = codeOwnerApprovalCheck.getFileStatusesAsSet(getChangeNotes(changeId));
-    fileCodeOwnerStatusSubject = assertThatCollection(fileCodeOwnerStatuses).onlyElement();
-    fileCodeOwnerStatusSubject.hasNewPathStatus().value().hasPathThat().isEqualTo(path);
-    fileCodeOwnerStatusSubject
-        .hasNewPathStatus()
-        .value()
-        .hasStatusThat()
-        .isEqualTo(CodeOwnerStatus.APPROVED);
+    assertThatCollection(fileCodeOwnerStatuses)
+        .containsExactly(FileCodeOwnerStatus.addition(path, CodeOwnerStatus.APPROVED));
   }
 
   @Test
@@ -1953,14 +1537,9 @@
     // Check that the file is not approved.
     ImmutableSet<FileCodeOwnerStatus> fileCodeOwnerStatuses =
         codeOwnerApprovalCheck.getFileStatusesAsSet(getChangeNotes(changeIdOfRevert));
-    FileCodeOwnerStatusSubject fileCodeOwnerStatusSubject =
-        assertThatCollection(fileCodeOwnerStatuses).onlyElement();
-    fileCodeOwnerStatusSubject.hasOldPathStatus().value().hasPathThat().isEqualTo(path);
-    fileCodeOwnerStatusSubject
-        .hasOldPathStatus()
-        .value()
-        .hasStatusThat()
-        .isEqualTo(CodeOwnerStatus.INSUFFICIENT_REVIEWERS);
+    assertThatCollection(fileCodeOwnerStatuses)
+        .containsExactly(
+            FileCodeOwnerStatus.deletion(path, CodeOwnerStatus.INSUFFICIENT_REVIEWERS));
   }
 
   @Test
@@ -1980,14 +1559,8 @@
     // Check that the file is approved since it's a pure revert.
     ImmutableSet<FileCodeOwnerStatus> fileCodeOwnerStatuses =
         codeOwnerApprovalCheck.getFileStatusesAsSet(getChangeNotes(changeIdOfRevert));
-    FileCodeOwnerStatusSubject fileCodeOwnerStatusSubject =
-        assertThatCollection(fileCodeOwnerStatuses).onlyElement();
-    fileCodeOwnerStatusSubject.hasOldPathStatus().value().hasPathThat().isEqualTo(path);
-    fileCodeOwnerStatusSubject
-        .hasOldPathStatus()
-        .value()
-        .hasStatusThat()
-        .isEqualTo(CodeOwnerStatus.APPROVED);
+    assertThatCollection(fileCodeOwnerStatuses)
+        .containsExactly(FileCodeOwnerStatus.deletion(path, CodeOwnerStatus.APPROVED));
   }
 
   @Test
@@ -2022,14 +1595,9 @@
     // Check that the file is not approved.
     ImmutableSet<FileCodeOwnerStatus> fileCodeOwnerStatuses =
         codeOwnerApprovalCheck.getFileStatusesAsSet(getChangeNotes(revertChange.changeId));
-    FileCodeOwnerStatusSubject fileCodeOwnerStatusSubject =
-        assertThatCollection(fileCodeOwnerStatuses).onlyElement();
-    fileCodeOwnerStatusSubject.hasNewPathStatus().value().hasPathThat().isEqualTo(path);
-    fileCodeOwnerStatusSubject
-        .hasNewPathStatus()
-        .value()
-        .hasStatusThat()
-        .isEqualTo(CodeOwnerStatus.INSUFFICIENT_REVIEWERS);
+    assertThatCollection(fileCodeOwnerStatuses)
+        .containsExactly(
+            FileCodeOwnerStatus.modification(path, CodeOwnerStatus.INSUFFICIENT_REVIEWERS));
   }
 
   @Test
@@ -2048,14 +1616,8 @@
     // approvals.
     ImmutableSet<FileCodeOwnerStatus> fileCodeOwnerStatuses =
         codeOwnerApprovalCheck.getFileStatusesAsSet(getChangeNotes(changeId));
-    FileCodeOwnerStatusSubject fileCodeOwnerStatusSubject =
-        assertThatCollection(fileCodeOwnerStatuses).onlyElement();
-    fileCodeOwnerStatusSubject.hasNewPathStatus().value().hasPathThat().isEqualTo(path);
-    fileCodeOwnerStatusSubject
-        .hasNewPathStatus()
-        .value()
-        .hasStatusThat()
-        .isEqualTo(CodeOwnerStatus.APPROVED);
+    assertThatCollection(fileCodeOwnerStatuses)
+        .containsExactly(FileCodeOwnerStatus.addition(path, CodeOwnerStatus.APPROVED));
 
     // Amend the change by another user, so that the other non-exempted user becomes the last
     // uploader.
@@ -2064,13 +1626,9 @@
     // Check that the file is no longer approved since the uploader is not exempted from requiring
     // code owner approvals.
     fileCodeOwnerStatuses = codeOwnerApprovalCheck.getFileStatusesAsSet(getChangeNotes(changeId));
-    fileCodeOwnerStatusSubject = assertThatCollection(fileCodeOwnerStatuses).onlyElement();
-    fileCodeOwnerStatusSubject.hasNewPathStatus().value().hasPathThat().isEqualTo(path);
-    fileCodeOwnerStatusSubject
-        .hasNewPathStatus()
-        .value()
-        .hasStatusThat()
-        .isEqualTo(CodeOwnerStatus.INSUFFICIENT_REVIEWERS);
+    assertThatCollection(fileCodeOwnerStatuses)
+        .containsExactly(
+            FileCodeOwnerStatus.addition(path, CodeOwnerStatus.INSUFFICIENT_REVIEWERS));
   }
 
   private ChangeNotes getChangeNotes(String changeId) throws Exception {