Improved test coverage (and slightly stricter error handling)

Author: kwi-dk

diff/diff_test.go

@@ -29,7 +29,7 @@ func init() {
 	time.Local = time.UTC
 }
 
-func TestReadQuotedFilename(t *testing.T) {
+func TestReadQuotedFilename_Success(t *testing.T) {
 	tests := []string{
 		`""`, "", "",
 		`"aaa"`, "aaa", "",
@@ -50,7 +50,21 @@ func TestReadQuotedFilename(t *testing.T) {
 	}
 }
 
-func TestParseDiffGitArgs(t *testing.T) {
+func TestReadQuotedFilename_Error(t *testing.T) {
+	tests := []string{
+		`"`,
+		`"\"`,
+		`"\xxx"`,
+	}
+	for _, input := range tests {
+		_, _, err := readQuotedFilename(input)
+		if err == nil {
+			t.Errorf("readQuotedFilename(`%s`): expected error", input)
+		}
+	}
+}
+
+func TestParseDiffGitArgs_Success(t *testing.T) {
 	tests := []string{
 		`aaa bbb`, "aaa", "bbb",
 		`"aaa" bbb`, "aaa", "bbb",
@@ -72,6 +86,28 @@ func TestParseDiffGitArgs(t *testing.T) {
 	}
 }
 
+func TestParseDiffGitArgs_Unsuccessful(t *testing.T) {
+	tests := []string{
+		``,
+		`hello_world.txt`,
+		`word `,
+		` word`,
+		`"a/bad_quoting b/bad_quoting`,
+		`a/bad_quoting "b/bad_quoting`,
+		`a/bad_quoting b/bad_quoting"`,
+		`"a/bad_quoting b/bad_quoting"`,
+		`"a/bad""b/bad"`,
+		`"a/bad" "b/bad" "c/bad"`,
+		`a/bad "b/bad" "c/bad"`,
+	}
+	for _, input := range tests {
+		success, first, second := parseDiffGitArgs(input)
+		if success {
+			t.Errorf("`diff --git %s`: expected unsuccessful; got `%s` and `%s`", input, first, second)
+		}
+	}
+}
+
 func TestParseHunkNoChunksize(t *testing.T) {
 	filename := "sample_no_chunksize.diff"
 	diffData, err := ioutil.ReadFile(filepath.Join("testdata", filename))

diff/parse.go

@@ -417,6 +417,9 @@ func parseDiffGitArgs(diffArgs string) (bool, string, string) {
 
 		secondSpace := strings.IndexByte(diffArgs[firstSpace+1:], ' ')
 		if secondSpace == -1 {
+			if diffArgs[firstSpace+1] == '"' {
+				return false, "", ""
+			}
 			return true, diffArgs[:firstSpace], diffArgs[firstSpace+1:]
 		}