Test that valid code owner config cannot be updated to be non-parseable

This slightly increases the test coverage for CodeOwnerConfigValidator
from 89.4% to 89.9%.

Signed-off-by: Edwin Kempin <ekempin@google.com>
Change-Id: I46fa0625f98b0f653e246c2b4daeb9d72d7b4446

javatests/com/google/gerrit/plugins/codeowners/acceptance/api/CodeOwnerConfigValidatorIT.java

diff --git a/javatests/com/google/gerrit/plugins/codeowners/acceptance/api/CodeOwnerConfigValidatorIT.java b/javatests/com/google/gerrit/plugins/codeowners/acceptance/api/CodeOwnerConfigValidatorIT.java
index 3dfa9db..c9f7916 100644
--- a/javatests/com/google/gerrit/plugins/codeowners/acceptance/api/CodeOwnerConfigValidatorIT.java
+++ b/javatests/com/google/gerrit/plugins/codeowners/acceptance/api/CodeOwnerConfigValidatorIT.java
@@ -648,6 +648,41 @@
   }
 
   @Test
+  public void cannotUpdateConfigToBeNonParseable() throws Exception {
+    CodeOwnerConfig.Key codeOwnerConfigKey = createCodeOwnerConfigKey("/");
+
+    // Create a code owner config without issues.
+    PushOneCommit.Result r =
+        createChange(
+            "Add code owners",
+            codeOwnerConfigOperations.codeOwnerConfig(codeOwnerConfigKey).getJGitFilePath(),
+            format(
+                CodeOwnerConfig.builder(codeOwnerConfigKey, TEST_REVISION)
+                    .addCodeOwnerSet(CodeOwnerSet.createWithoutPathExpressions(admin.email()))
+                    .build()));
+    r.assertOkStatus();
+
+    r =
+        createChange(
+            "Add code owners",
+            codeOwnerConfigOperations.codeOwnerConfig(codeOwnerConfigKey).getJGitFilePath(),
+            "INVALID");
+    assertFatalWithMessages(
+        r,
+        "invalid code owner config files",
+        String.format(
+            "invalid code owner config file '%s' (project = %s, branch = master):\n  %s",
+            codeOwnerConfigOperations.codeOwnerConfig(codeOwnerConfigKey).getFilePath(),
+            project,
+            getParsingErrorMessage(
+                ImmutableMap.of(
+                    FindOwnersBackend.class,
+                    "invalid line: INVALID",
+                    ProtoBackend.class,
+                    "1:8: expected \"{\""))));
+  }
+
+  @Test
   public void issuesAreReportedForAllInvalidConfigs() throws Exception {
     CodeOwnerConfig.Key codeOwnerConfigKey1 = createCodeOwnerConfigKey("/");
     CodeOwnerConfig.Key codeOwnerConfigKey2 = createCodeOwnerConfigKey("/foo/bar/");