Merge pull request #1498 from cloudflare/blame

Check content for changes when running git blame

Author: prymitive

cmd/pint/tests/0069_bitbucket_unmodified.txt

@@ -147,22 +147,22 @@ annotations:
     link: https://cloudflare.github.io/pint/checks/alerts/for.html
     line: 3
   - path: rules.yml
-    message: "alerts/comparison: always firing alert"
+    message: "Problem reported on unmodified line 5, annotation moved here: alerts/comparison: always firing alert"
     severity: LOW
     type: CODE_SMELL
     link: https://cloudflare.github.io/pint/checks/alerts/comparison.html
-    line: 5
+    line: 4
   - path: rules.yml
-    message: "promql/regexp: redundant regexp"
+    message: "Problem reported on unmodified line 5, annotation moved here: promql/regexp: redundant regexp"
     severity: LOW
     type: CODE_SMELL
     link: https://cloudflare.github.io/pint/checks/promql/regexp.html
-    line: 5
+    line: 4
   - path: rules.yml
-    message: "alerts/for: redundant field with default value"
+    message: "Problem reported on unmodified line 6, annotation moved here: alerts/for: redundant field with default value"
     severity: LOW
     type: CODE_SMELL
     link: https://cloudflare.github.io/pint/checks/alerts/for.html
-    line: 6
+    line: 4
 --- END ---
 

cmd/pint/tests/0123_ci_owner_allowed.txt

@@ -148,6 +148,6 @@ annotations:
     severity: MEDIUM
     type: BUG
     link: https://cloudflare.github.io/pint/checks/rule/owner.html
-    line: 8
+    line: 7
 --- END ---
 

docs/changelog.md

@@ -5,6 +5,7 @@
 ### Fixed
 
 - Fixed incorrect incorrect suggestions generated by [query/cost](checks/query/cost.md) check.
+- Fixed unmodified lines incorrectly marked as modified when running `pint ci`.
 
 ## v0.74.4
 

internal/discovery/git_branch_test.go

@@ -867,7 +867,7 @@ groups:
 						Name:          "rules.yml",
 						SymlinkTarget: "rules.yml",
 					},
-					ModifiedLines: []int{8, 9},
+					ModifiedLines: []int{8},
 					Rule:          mustParse(7, "- alert: rule2\n  expr: sum(foo) by(job)\n"),
 				},
 			},
@@ -1080,7 +1080,7 @@ groups:
 						Name:          "rules.yml",
 						SymlinkTarget: "rules.yml",
 					},
-					ModifiedLines: []int{3, 11, 12, 13, 14, 15, 16},
+					ModifiedLines: []int{3, 11, 12, 15, 16},
 					PathError: parser.ParseError{
 						Line: 11,
 						Err:  errors.New("could not find expected ':'"),

internal/git/changes.go

@@ -204,7 +204,7 @@ func Changes(cmd CommandRunner, baseBranch string, filter PathFilter) ([]*FileCh
 			slog.Debug("File was turned into a symlink", slog.String("path", change.Path.After.Name))
 			change.Body.ModifiedLines = CountLines(change.Body.After)
 		case change.Path.Before.Type != Missing && change.Path.After.Type != Missing && change.Path.After.Type != Symlink:
-			change.Body.ModifiedLines, err = getModifiedLines(cmd, change.Commits, change.Path.After.EffectivePath(), lastCommit)
+			change.Body.ModifiedLines, err = getModifiedLines(cmd, change.Commits, change.Path.After.EffectivePath(), lastCommit, change.Body.Before, change.Body.After)
 			if err != nil {
 				return nil, fmt.Errorf("failed to run git blame for %s: %w", change.Path.After.EffectivePath(), err)
 			}
@@ -261,7 +261,7 @@ func getChangeByPath(changes []*FileChange, fpath string) *FileChange {
 	return nil
 }
 
-func getModifiedLines(cmd CommandRunner, commits []string, fpath, atCommit string) ([]int, error) {
+func getModifiedLines(cmd CommandRunner, commits []string, fpath, atCommit string, bodyBefore, bodyAfter []byte) ([]int, error) {
 	slog.Debug("Getting list of modified lines",
 		slog.Any("commits", commits),
 		slog.String("path", fpath),
@@ -271,11 +271,21 @@ func getModifiedLines(cmd CommandRunner, commits []string, fpath, atCommit strin
 		return nil, err
 	}
 
+	linesBefore := bytes.Split(bodyBefore, []byte("\n"))
+	linesAfter := bytes.Split(bodyAfter, []byte("\n"))
+
 	modLines := make([]int, 0, len(lines))
 	for _, line := range lines {
 		if !slices.Contains(commits, line.Commit) && line.Line == line.PrevLine {
 			continue
 		}
+
+		if line.PrevLine <= len(linesBefore) && line.Line <= len(linesAfter) {
+			if bytes.Equal(linesBefore[line.PrevLine-1], linesAfter[line.Line-1]) {
+				continue
+			}
+		}
+
 		modLines = append(modLines, line.Line)
 	}
 	slog.Debug("List of modified lines",

internal/git/changes_test.go

@@ -188,7 +188,7 @@ func TestChanges(t *testing.T) {
 					Body: git.BodyDiff{
 						Before:        []byte("foo"),
 						After:         []byte("foo"),
-						ModifiedLines: []int{1},
+						ModifiedLines: []int{},
 					},
 				},
 			},
@@ -583,7 +583,7 @@ func TestChanges(t *testing.T) {
 					Body: git.BodyDiff{
 						Before:        []byte("l1\nl2\nl3\n"),
 						After:         []byte("l1\nl3\n"),
-						ModifiedLines: []int{2},
+						ModifiedLines: []int{1, 2},
 					},
 				},
 			},