add (*Blame).HunkByLine (git_blame_get_hunk_byline) and test

2 files changed, 30 insertions, 11 deletions

diff --git a/blame.go b/blame.go
index cd5665a..c24c934 100644
--- a/blame.go
+++ b/blame.go
@@ -99,6 +99,14 @@ func (blame *Blame) HunkByIndex(index int) (BlameHunk, error) {
 	return blameHunkFromC(ptr), nil
 }
 
+func (blame *Blame) HunkByLine(lineno int) (BlameHunk, error) {
+	ptr := C.git_blame_get_hunk_byline(blame.ptr, C.uint32_t(lineno))
+	if ptr == nil {
+		return BlameHunk{}, ErrInvalid
+	}
+	return blameHunkFromC(ptr), nil
+}
+
 func newBlameFromC(ptr *C.git_blame) *Blame {
 	if ptr == nil {
 		return nil
diff --git a/blame_test.go b/blame_test.go
index 7c730a0..1785042 100644
--- a/blame_test.go
+++ b/blame_test.go
@@ -27,9 +27,7 @@ func TestBlame(t *testing.T) {
 		t.Errorf("got hunk count %d, want 2", blame.HunkCount())
 	}
 
-	hunk1, err := blame.HunkByIndex(0)
-	checkFatal(t, err)
-	checkHunk(t, hunk1, BlameHunk{
+	wantHunk1 := BlameHunk{
 		LinesInHunk:          1,
 		FinalCommitId:        commitId1,
 		FinalStartLineNumber: 1,
@@ -37,11 +35,8 @@ func TestBlame(t *testing.T) {
 		OrigPath:             "README",
 		OrigStartLineNumber:  1,
 		Boundary:             true,
-	})
-
-	hunk2, err := blame.HunkByIndex(1)
-	checkFatal(t, err)
-	checkHunk(t, hunk2, BlameHunk{
+	}
+	wantHunk2 := BlameHunk{
 		LinesInHunk:          2,
 		FinalCommitId:        commitId2,
 		FinalStartLineNumber: 2,
@@ -49,15 +44,31 @@ func TestBlame(t *testing.T) {
 		OrigPath:             "README",
 		OrigStartLineNumber:  2,
 		Boundary:             false,
-	})
+	}
+
+	hunk1, err := blame.HunkByIndex(0)
+	checkFatal(t, err)
+	checkHunk(t, "index 0", hunk1, wantHunk1)
+
+	hunk2, err := blame.HunkByIndex(1)
+	checkFatal(t, err)
+	checkHunk(t, "index 1", hunk2, wantHunk2)
+
+	hunkLine1, err := blame.HunkByLine(1)
+	checkFatal(t, err)
+	checkHunk(t, "line 1", hunkLine1, wantHunk1)
+
+	hunkLine2, err := blame.HunkByLine(3)
+	checkFatal(t, err)
+	checkHunk(t, "line 2", hunkLine2, wantHunk2)
 }
 
-func checkHunk(t *testing.T, hunk, want BlameHunk) {
+func checkHunk(t *testing.T, label string, hunk, want BlameHunk) {
 	hunk.FinalSignature = nil
 	want.FinalSignature = nil
 	hunk.OrigSignature = nil
 	want.OrigSignature = nil
 	if !reflect.DeepEqual(hunk, want) {
-		t.Fatalf("got hunk %+v, want %+v", hunk, want)
+		t.Fatalf("%s: got hunk %+v, want %+v", label, hunk, want)
 	}
 }