Use raw string literal syntax only for valid UTF-8 (#211)

google · Jun 10, 2020 · a171aa7 · a171aa7
1 parent 88849e8
commit a171aa7
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Showing 3 changed files with 12 additions and 1 deletion.
diff --git a/cmp/compare_test.go b/cmp/compare_test.go
@@ -822,6 +822,11 @@ func reporterTests() []test {
 	)
 
 	return []test{{
+		label:     "/InvalidUTF8",
+		x:         MyString("\xed\xa0\x80"),
+		wantEqual: false,
+		reason:    "invalid UTF-8 should format as quoted string",
+	}, {
 		label:     label,
 		x:         MyComposite{IntsA: []int8{11, 12, 13, 14, 15, 16, 17, 18, 19, 20, 21, 22, 23, 24, 25, 26, 27, 28, 29}},
 		y:         MyComposite{IntsA: []int8{10, 11, 21, 13, 14, 15, 16, 17, 18, 19, 20, 21, 22, 23, 24, 25, 26, 27, 28, 29}},

diff --git a/cmp/report_reflect.go b/cmp/report_reflect.go
@@ -10,6 +10,7 @@ import (
 	"strconv"
 	"strings"
 	"unicode"
+	"unicode/utf8"
 
 	"github.com/google/go-cmp/cmp/internal/flags"
 	"github.com/google/go-cmp/cmp/internal/value"
@@ -235,7 +236,7 @@ func formatString(s string) string {
 	rawInvalid := func(r rune) bool {
 		return r == '`' || r == '\n' || !(unicode.IsPrint(r) || r == '\t')
 	}
-	if strings.IndexFunc(s, rawInvalid) < 0 {
+	if utf8.ValidString(s) && strings.IndexFunc(s, rawInvalid) < 0 {
 		return "`" + s + "`"
 	}
 	return qs

diff --git a/cmp/testdata/diffs b/cmp/testdata/diffs
@@ -258,6 +258,11 @@
   	})),
   }
 >>> TestDiff/Transformer#05
+<<< TestDiff//InvalidUTF8
+  interface{}(
+- 	cmp_test.MyString("\xed\xa0\x80"),
+  )
+>>> TestDiff//InvalidUTF8
 <<< TestDiff/Reporter
   cmp_test.MyComposite{
   	... // 3 identical fields