Merge "Fix an internal server error when diffing patch sets (non-merge commit)"

java/com/google/gerrit/server/patch/PatchScriptBuilder.java

@@ -272,6 +272,12 @@ class PatchScriptBuilder {
       return;
     }
 
+    if (edits.isEmpty() && (aSize != bSize)) {
+      // Only edits due to rebase were present. If we now added the edits for the newlines, the
+      // code which later assembles the file contents would fail.
+      return;
+    }
+
     Optional<Edit> lastEdit = getLast(edits);
     if (isNewlineAtEndDeleted(a, b)) {
       Optional<Edit> lastLineEdit = lastEdit.filter(edit -> edit.getEndA() == aSize);

javatests/com/google/gerrit/acceptance/api/revision/RevisionDiffIT.java

@@ -41,6 +41,7 @@ import com.google.gerrit.extensions.common.ChangeType;
 import com.google.gerrit.extensions.common.DiffInfo;
 import com.google.gerrit.extensions.common.FileInfo;
 import com.google.gerrit.extensions.restapi.BinaryResult;
+import com.google.gerrit.extensions.restapi.RestApiException;
 import com.google.gerrit.testing.ConfigSuite;
 import java.awt.image.BufferedImage;
 import java.io.ByteArrayOutputStream;
@@ -577,6 +578,109 @@ public class RevisionDiffIT extends AbstractDaemonTest {
     assertThat(changedFiles.get(FILE_NAME)).linesDeleted().isEqualTo(1);
   }
 
+  @Test
+  public void addedNewlineAtEndOfFileIsMarkedInDiffWhenOtherwiseOnlyEditsDueToRebaseExist()
+      throws Exception {
+    addModifiedPatchSet(changeId, FILE_NAME, fileContent -> fileContent.concat("Line 101"));
+    String previousPatchSetId = gApi.changes().id(changeId).get().currentRevision;
+    String newBaseFileContent = FILE_CONTENT.replace("Line 70\n", "Line seventy\n");
+    ObjectId commit2 = addCommit(commit1, FILE_NAME, newBaseFileContent);
+    rebaseChangeOn(changeId, commit2);
+    addModifiedPatchSet(changeId, FILE_NAME, fileContent -> fileContent.concat("\n"));
+
+    DiffInfo diffInfo =
+        getDiffRequest(changeId, CURRENT, FILE_NAME)
+            .withWhitespace(DiffPreferencesInfo.Whitespace.IGNORE_NONE)
+            .withBase(previousPatchSetId)
+            .get();
+    assertThat(diffInfo).content().element(0).commonLines().isNotEmpty();
+    assertThat(diffInfo).content().element(1).isNotNull(); // Line 70 modification
+    assertThat(diffInfo).content().element(2).commonLines().isNotEmpty();
+    assertThat(diffInfo).content().element(3).linesOfA().containsExactly("Line 101");
+    assertThat(diffInfo).content().element(3).linesOfB().containsExactly("Line 101", "");
+
+    assertThat(diffInfo).metaA().totalLineCount().isEqualTo(101);
+    assertThat(diffInfo).metaB().totalLineCount().isEqualTo(102);
+  }
+
+  @Test
+  // TODO: Fix this issue. This test documents the current behavior and ensures that we at least
+  //  don't run into an internal server error.
+  public void addedNewlineAtEndOfFileIsNotIdentifiedAsDueToRebaseEvenThoughItShould()
+      throws Exception {
+    String baseFileContent = FILE_CONTENT.concat("Line 101");
+    ObjectId commit2 = addCommit(commit1, FILE_NAME, baseFileContent);
+    rebaseChangeOn(changeId, commit2);
+    // Add a comment so that file contents are not 'skipped'. To be able to add a comment, touch
+    // (= modify) the file in the change.
+    addModifiedPatchSet(
+        changeId, FILE_NAME, fileContent -> fileContent.replace("Line 2\n", "Line two\n"));
+    CommentInput comment = createCommentInput(3, 0, 4, 0, "Comment to not skip file content.");
+    addCommentTo(changeId, CURRENT, FILE_NAME, comment);
+    String previousPatchSetId = gApi.changes().id(changeId).get().currentRevision;
+    String newBaseFileContent = baseFileContent.concat("\n");
+    ObjectId commit3 = addCommit(commit2, FILE_NAME, newBaseFileContent);
+    rebaseChangeOn(changeId, commit3);
+
+    DiffInfo diffInfo =
+        getDiffRequest(changeId, CURRENT, FILE_NAME)
+            .withWhitespace(DiffPreferencesInfo.Whitespace.IGNORE_ALL)
+            .withBase(previousPatchSetId)
+            .get();
+    assertThat(diffInfo).content().element(0).commonLines().isNotEmpty();
+    assertThat(diffInfo).content().element(1).linesOfA().isNull();
+    assertThat(diffInfo).content().element(1).linesOfB().containsExactly("");
+    // This should actually be isDueToRebase().
+    assertThat(diffInfo).content().element(1).isNotDueToRebase();
+  }
+
+  @Test
+  public void
+      addedNewlineAtEndOfFileIsMarkedWhenEditDueToRebaseIncreasedLineCountAndWhitespaceConsidered()
+          throws Exception {
+    addModifiedPatchSet(changeId, FILE_NAME, fileContent -> fileContent.concat("Line 101"));
+    String previousPatchSetId = gApi.changes().id(changeId).get().currentRevision;
+    String newBaseFileContent = FILE_CONTENT.replace("Line 70\n", "Line 70\nLine 70.5\n");
+    ObjectId commit2 = addCommit(commit1, FILE_NAME, newBaseFileContent);
+    rebaseChangeOn(changeId, commit2);
+    addModifiedPatchSet(changeId, FILE_NAME, fileContent -> fileContent.concat("\n"));
+
+    DiffInfo diffInfo =
+        getDiffRequest(changeId, CURRENT, FILE_NAME)
+            .withWhitespace(DiffPreferencesInfo.Whitespace.IGNORE_NONE)
+            .withBase(previousPatchSetId)
+            .get();
+    assertThat(diffInfo).content().element(0).commonLines().isNotEmpty();
+    assertThat(diffInfo).content().element(1).isNotNull(); // Line 70.5 insertion
+    assertThat(diffInfo).content().element(2).commonLines().isNotEmpty();
+    assertThat(diffInfo).content().element(3).linesOfA().containsExactly("Line 101");
+    assertThat(diffInfo).content().element(3).linesOfB().containsExactly("Line 101", "");
+
+    assertThat(diffInfo).metaA().totalLineCount().isEqualTo(101);
+    assertThat(diffInfo).metaB().totalLineCount().isEqualTo(103);
+  }
+
+  @Test
+  // TODO: Fix this issue. This test documents the current behavior and ensures that we at least
+  //  don't run into an internal server error.
+  public void
+      addedNewlineAtEndOfFileIsNotMarkedWhenEditDueToRebaseIncreasedLineCountAndWhitespaceIgnoredEvenThoughItShould()
+          throws Exception {
+    addModifiedPatchSet(changeId, FILE_NAME, fileContent -> fileContent.concat("Line 101"));
+    String previousPatchSetId = gApi.changes().id(changeId).get().currentRevision;
+    String newBaseFileContent = FILE_CONTENT.replace("Line 70\n", "Line 70\nLine 70.5\n");
+    ObjectId commit2 = addCommit(commit1, FILE_NAME, newBaseFileContent);
+    rebaseChangeOn(changeId, commit2);
+    addModifiedPatchSet(changeId, FILE_NAME, fileContent -> fileContent.concat("\n"));
+
+    DiffInfo diffInfo =
+        getDiffRequest(changeId, CURRENT, FILE_NAME)
+            .withWhitespace(DiffPreferencesInfo.Whitespace.IGNORE_ALL)
+            .withBase(previousPatchSetId)
+            .get();
+    assertThat(diffInfo).content().element(0).numberOfSkippedLines().isGreaterThan(0);
+  }
+
   @Test
   public void addedLastLineWithoutNewlineBeforeAndAfterwardsIsMarkedInDiff() throws Exception {
     addModifiedPatchSet(changeId, FILE_NAME, fileContent -> fileContent.concat("Line 101"));
@@ -2374,9 +2478,7 @@ public class RevisionDiffIT extends AbstractDaemonTest {
     addModifiedPatchSet(changeId, FILE_NAME, content -> content.replace("Line 2\n", "Line two\n"));
     String previousPatchSetId = gApi.changes().id(changeId).get().currentRevision;
     CommentInput comment = createCommentInput(2, 0, 3, 0, "Should be 'Line 2'.");
-    ReviewInput reviewInput = new ReviewInput();
+    addCommentTo(changeId, previousPatchSetId, FILE_NAME, comment);
-    reviewInput.comments = ImmutableMap.of(FILE_NAME, ImmutableList.of(comment));
-    gApi.changes().id(changeId).revision(previousPatchSetId).review(reviewInput);
     addModifiedPatchSet(
         changeId, FILE_NAME2, content -> content.replace("2nd line\n", "Second line\n"));
 
@@ -2394,6 +2496,112 @@ public class RevisionDiffIT extends AbstractDaemonTest {
         .inOrder();
   }
 
+  @Test
+  public void
+      diffOfFileWithOnlyRebaseHunksAndWithCommentAndConsideringWhitespaceReturnsFileContents()
+          throws Exception {
+    addModifiedPatchSet(changeId, FILE_NAME, content -> content.replace("Line 2\n", "Line two\n"));
+    String previousPatchSetId = gApi.changes().id(changeId).get().currentRevision;
+    String newBaseFileContent = FILE_CONTENT.replace("Line 70\n", "Line seventy\n");
+    ObjectId commit2 = addCommit(commit1, FILE_NAME, newBaseFileContent);
+    rebaseChangeOn(changeId, commit2);
+    CommentInput comment = createCommentInput(2, 0, 3, 0, "Should be 'Line 2'.");
+    addCommentTo(changeId, previousPatchSetId, FILE_NAME, comment);
+
+    DiffInfo diffInfo =
+        getDiffRequest(changeId, CURRENT, FILE_NAME)
+            .withBase(previousPatchSetId)
+            .withWhitespace(DiffPreferencesInfo.Whitespace.IGNORE_NONE)
+            .get();
+    // We don't list the full file contents here as that is not the focus of this test.
+    assertThat(diffInfo)
+        .content()
+        .element(0)
+        .commonLines()
+        .containsAtLeast("Line 1", "Line two", "Line 3", "Line 4", "Line 5")
+        .inOrder();
+  }
+
+  @Test
+  public void diffOfFileWithOnlyRebaseHunksAndWithCommentAndIgnoringWhitespaceReturnsFileContents()
+      throws Exception {
+    addModifiedPatchSet(changeId, FILE_NAME, content -> content.replace("Line 2\n", "Line two\n"));
+    String previousPatchSetId = gApi.changes().id(changeId).get().currentRevision;
+    String newBaseFileContent = FILE_CONTENT.replace("Line 70\n", "Line seventy\n");
+    ObjectId commit2 = addCommit(commit1, FILE_NAME, newBaseFileContent);
+    rebaseChangeOn(changeId, commit2);
+    CommentInput comment = createCommentInput(2, 0, 3, 0, "Should be 'Line 2'.");
+    addCommentTo(changeId, previousPatchSetId, FILE_NAME, comment);
+
+    DiffInfo diffInfo =
+        getDiffRequest(changeId, CURRENT, FILE_NAME)
+            .withBase(previousPatchSetId)
+            .withWhitespace(DiffPreferencesInfo.Whitespace.IGNORE_ALL)
+            .get();
+    // We don't list the full file contents here as that is not the focus of this test.
+    assertThat(diffInfo)
+        .content()
+        .element(0)
+        .commonLines()
+        .containsAtLeast("Line 1", "Line two", "Line 3", "Line 4", "Line 5")
+        .inOrder();
+  }
+
+  @Test
+  public void
+      diffOfFileWithMultilineRebaseHunkAddingNewlineAtEndOfFileAndWithCommentReturnsFileContents()
+          throws Exception {
+    String baseFileContent = FILE_CONTENT.concat("Line 101");
+    ObjectId commit2 = addCommit(commit1, FILE_NAME, baseFileContent);
+    rebaseChangeOn(changeId, commit2);
+    addModifiedPatchSet(changeId, FILE_NAME, content -> content.replace("Line 2\n", "Line two\n"));
+    String previousPatchSetId = gApi.changes().id(changeId).get().currentRevision;
+    String newBaseFileContent = baseFileContent.concat("\nLine 102\nLine 103\n");
+    ObjectId commit3 = addCommit(commit2, FILE_NAME, newBaseFileContent);
+    rebaseChangeOn(changeId, commit3);
+    CommentInput comment = createCommentInput(2, 0, 3, 0, "Should be 'Line 2'.");
+    addCommentTo(changeId, previousPatchSetId, FILE_NAME, comment);
+
+    DiffInfo diffInfo =
+        getDiffRequest(changeId, CURRENT, FILE_NAME)
+            .withBase(previousPatchSetId)
+            .withWhitespace(DiffPreferencesInfo.Whitespace.IGNORE_NONE)
+            .get();
+    // We don't list the full file contents here as that is not the focus of this test.
+    assertThat(diffInfo)
+        .content()
+        .element(0)
+        .commonLines()
+        .containsAtLeast("Line 1", "Line two", "Line 3", "Line 4", "Line 5")
+        .inOrder();
+  }
+
+  @Test
+  public void
+      diffOfFileWithMultilineRebaseHunkRemovingNewlineAtEndOfFileAndWithCommentReturnsFileContents()
+          throws Exception {
+    addModifiedPatchSet(changeId, FILE_NAME, content -> content.replace("Line 2\n", "Line two\n"));
+    String previousPatchSetId = gApi.changes().id(changeId).get().currentRevision;
+    String newBaseFileContent = FILE_CONTENT.concat("Line 101\nLine 103\nLine 104");
+    ObjectId commit2 = addCommit(commit1, FILE_NAME, newBaseFileContent);
+    rebaseChangeOn(changeId, commit2);
+    CommentInput comment = createCommentInput(2, 0, 3, 0, "Should be 'Line 2'.");
+    addCommentTo(changeId, previousPatchSetId, FILE_NAME, comment);
+
+    DiffInfo diffInfo =
+        getDiffRequest(changeId, CURRENT, FILE_NAME)
+            .withBase(previousPatchSetId)
+            .withWhitespace(DiffPreferencesInfo.Whitespace.IGNORE_NONE)
+            .get();
+    // We don't list the full file contents here as that is not the focus of this test.
+    assertThat(diffInfo)
+        .content()
+        .element(0)
+        .commonLines()
+        .containsAtLeast("Line 1", "Line two", "Line 3", "Line 4", "Line 5")
+        .inOrder();
+  }
+
   @Test
   public void diffOfNonExistentFileIsAnEmptyDiffResult() throws Exception {
     addModifiedPatchSet(changeId, FILE_NAME, content -> content.replace("Line 2\n", "Line two\n"));
@@ -2432,9 +2640,7 @@ public class RevisionDiffIT extends AbstractDaemonTest {
         changeId, FILE_NAME, content -> content.replace("Line 20\n", "Line twenty\n"));
     String previousPatchSetId = gApi.changes().id(changeId).get().currentRevision;
     CommentInput comment = createCommentInput(20, 0, 21, 0, "Should be 'Line 20'.");
-    ReviewInput reviewInput = new ReviewInput();
+    addCommentTo(changeId, previousPatchSetId, FILE_NAME, comment);
-    reviewInput.comments = ImmutableMap.of(FILE_NAME, ImmutableList.of(comment));
-    gApi.changes().id(changeId).revision(previousPatchSetId).review(reviewInput);
     addModifiedPatchSet(
         changeId, FILE_NAME2, content -> content.replace("2nd line\n", "Second line\n"));
 
@@ -2476,9 +2682,7 @@ public class RevisionDiffIT extends AbstractDaemonTest {
     addModifiedPatchSet(changeId, FILE_NAME, content -> content.replace("Line 2\n", "Line two\n"));
     String previousPatchSetId = gApi.changes().id(changeId).get().currentRevision;
     CommentInput comment = createCommentInput(2, 0, 3, 0, "Should be 'Line 2'.");
-    ReviewInput reviewInput = new ReviewInput();
+    addCommentTo(changeId, previousPatchSetId, FILE_NAME, comment);
-    reviewInput.comments = ImmutableMap.of(FILE_NAME, ImmutableList.of(comment));
-    gApi.changes().id(changeId).revision(previousPatchSetId).review(reviewInput);
     String newFilePath = "a_new_file.txt";
     gApi.changes().id(changeId).edit().renameFile(FILE_NAME, newFilePath);
     gApi.changes().id(changeId).edit().publish();
@@ -2507,6 +2711,14 @@ public class RevisionDiffIT extends AbstractDaemonTest {
     return comment;
   }
 
+  private void addCommentTo(
+      String changeId, String previousPatchSetId, String fileName, CommentInput comment)
+      throws RestApiException {
+    ReviewInput reviewInput = new ReviewInput();
+    reviewInput.comments = ImmutableMap.of(fileName, ImmutableList.of(comment));
+    gApi.changes().id(changeId).revision(previousPatchSetId).review(reviewInput);
+  }
+
   private void assertDiffForNewFile(
       PushOneCommit.Result pushResult, String path, String expectedContentSideB) throws Exception {
     DiffInfo diff =