Fix links and file name in emails for patchset-level comments

Currently, emails that include patchset-level comments will have
links to the file /PATCHSET_LEVEL. This is changed in such way
that all of those links will now link to the comments tab.

Also, the name of the file in the email was /PATCHSET_LEVEL, but now
it is "Patchset".

There are currently no tests about links being valid, simply because
it requires a brute-force string comparison. In my opinion, such a
test won't add much value anyway.

There is now a test about patchset level email notifications, that
confirms that the name /PATCHSET_LEVEL was changed to Patchset Level,
and also confirms that any links involving "/PATCHSET_LEVEL" were
omitted.

Change-Id: I08b6bcaff618ce4a645b1de936339f31d0fe0b15

java/com/google/gerrit/server/config/UrlFormatter.java

diff --git a/java/com/google/gerrit/server/config/UrlFormatter.java b/java/com/google/gerrit/server/config/UrlFormatter.java
index 6b2510e..8fc0d9e 100644
--- a/java/com/google/gerrit/server/config/UrlFormatter.java
+++ b/java/com/google/gerrit/server/config/UrlFormatter.java
@@ -47,6 +47,11 @@
     return getWebUrl().map(url -> url + "c/" + project.get() + "/+/" + id.get());
   }
 
+  /** Returns the URL for viewing the comment tab view of a change. */
+  default Optional<String> getCommentsTabView(Change change) {
+    return getChangeViewUrl(change.getProject(), change.getId()).map(url -> url + "?tab=comments");
+  }
+
   /** Returns the URL for viewing a file in a given patch set of a change. */
   default Optional<String> getPatchFileView(Change change, int patchsetId, String filename) {
     return getChangeViewUrl(change.getProject(), change.getId())

java/com/google/gerrit/server/mail/send/CommentSender.java

diff --git a/java/com/google/gerrit/server/mail/send/CommentSender.java b/java/com/google/gerrit/server/mail/send/CommentSender.java
index 48d342e..deaa926 100644
--- a/java/com/google/gerrit/server/mail/send/CommentSender.java
+++ b/java/com/google/gerrit/server/mail/send/CommentSender.java
@@ -88,6 +88,11 @@
           .orElse(null);
     }
 
+    /** @return a web link to the comment tab view of a change. */
+    public String getCommentsTabLink() {
+      return args.urlFormatter.get().getCommentsTabView(change).orElse(null);
+    }
+
     /**
      * @return A title for the group, i.e. "Commit Message", "Merge List", or "File [[filename]]".
      */
@@ -96,6 +101,8 @@
         return "Commit Message";
       } else if (Patch.MERGE_LIST.equals(filename)) {
         return "Merge List";
+      } else if (Patch.PATCHSET_LEVEL.equals(filename)) {
+        return "Patchset";
       } else {
         return "File " + filename;
       }
@@ -379,7 +386,11 @@
 
     for (CommentSender.FileCommentGroup group : getGroupedInlineComments(repo)) {
       Map<String, Object> groupData = new HashMap<>();
-      groupData.put("link", group.getFileLink());
+      if (group.filename.equals(Patch.PATCHSET_LEVEL)) {
+        groupData.put("link", group.getCommentsTabLink());
+      } else {
+        groupData.put("link", group.getFileLink());
+      }
       groupData.put("title", group.getTitle());
       groupData.put("patchSetId", group.patchSetId);
 
@@ -407,7 +418,10 @@
         commentData.put("startLine", startLine);
 
         // Set the comment link.
-        if (comment.lineNbr == 0) {
+
+        if (comment.key.filename.equals(Patch.PATCHSET_LEVEL)) {
+          commentData.put("link", group.getCommentsTabLink());
+        } else if (comment.lineNbr == 0) {
           commentData.put("link", group.getFileLink());
         } else {
           commentData.put("link", group.getCommentLink(comment.side, startLine));

javatests/com/google/gerrit/acceptance/server/change/CommentsIT.java

diff --git a/javatests/com/google/gerrit/acceptance/server/change/CommentsIT.java b/javatests/com/google/gerrit/acceptance/server/change/CommentsIT.java
index 4fac821..e48c9d5 100644
--- a/javatests/com/google/gerrit/acceptance/server/change/CommentsIT.java
+++ b/javatests/com/google/gerrit/acceptance/server/change/CommentsIT.java
@@ -212,6 +212,20 @@
   }
 
   @Test
+  public void patchsetLevelCommentEmailNotification() throws Exception {
+    PushOneCommit.Result result = createChange();
+    String changeId = result.getChangeId();
+    String ps1 = result.getCommit().name();
+
+    CommentInput comment = newCommentWithOnlyMandatoryFields(PATCHSET_LEVEL, "comment");
+    addComments(changeId, ps1, comment);
+
+    String emailBody = Iterables.getOnlyElement(email.getMessages()).body();
+    assertThat(emailBody).contains("Patchset");
+    assertThat(emailBody).doesNotContain("/PATCHSET_LEVEL");
+  }
+
+  @Test
   public void patchsetLevelCommentCantHaveLine() throws Exception {
     PushOneCommit.Result result = createChange();
     String changeId = result.getChangeId();

polygerrit-ui/app/constants/constants.js

diff --git a/polygerrit-ui/app/constants/constants.js b/polygerrit-ui/app/constants/constants.js
index 74ebebd..ff34442 100644
--- a/polygerrit-ui/app/constants/constants.js
+++ b/polygerrit-ui/app/constants/constants.js
@@ -21,6 +21,9 @@
  */
 export const PrimaryTab = {
   FILES: 'files',
+  /**
+   * When renaming this, the links in UrlFormatter must be updated.
+   */
   COMMENT_THREADS: 'comments',
   FINDINGS: 'findings',
 };