Update strings.format to adhere to the specification

WORKSPACE

@@ -101,8 +101,8 @@ go_repository(
 go_repository(
     name = "dev_cel_expr",
     importpath = "cel.dev/expr",
-    sum = "h1:NciYrtDRIR0lNCnH1LFJegdjspNx9fI59O7TWcua/W4=",
-    version = "v0.19.1",
+    sum = "h1:o+Wj235dy4gFYlYin3JsMpp3EEfMrPm/6tdoyjT98S0=",
+    version = "v0.21.2",
 )
 
 # local_repository(

cel/cel_example_test.go

@@ -68,7 +68,7 @@ func Example() {
 	}
 
 	fmt.Println(out)
-	// Output:Hello world! Nice to meet you, I'm CEL.
+	// Output:"Hello \"world\"! Nice to meet you, I'm \"CEL\".\n"
 }
 
 func Example_globalOverload() {
@@ -116,7 +116,7 @@ func Example_globalOverload() {
 	}
 
 	fmt.Println(out)
-	// Output:CEL and world are shaking hands.
+	// Output:"\"CEL\" and \"world\" are shaking hands.\n"
 }
 
 func Example_statefulOverload() {

cel/cel_test.go

@@ -2438,7 +2438,7 @@ func TestQuotedFields(t *testing.T) {
 		},
 		{
 			expr:        "{'key-1': 64}.`key-2`",
-			errorSubstr: "no such key: key-2",
+			errorSubstr: "no such key: \"key-2\"",
 		},
 		{
 			expr: "has({'key-1': 64}.`key-1`)",
@@ -2951,7 +2951,7 @@ func TestOptionalValuesEval(t *testing.T) {
 					},
 				},
 			},
-			out: "no such key: a",
+			out: "no such key: \"a\"",
 		},
 		{
 			expr: `m.?c.missing.or(m.?c['dashed-index']).orValue('').size()`,
@@ -3136,23 +3136,23 @@ func TestEnableErrorOnBadPresenceTest(t *testing.T) {
 		},
 		{
 			expr: `{'null_field': dyn(null)}.?null_field.?nested`,
-			out:  "no such key: nested",
+			out:  "no such key: \"nested\"",
 		},
 		{
 			expr: `{'zero_field': dyn(0)}.?zero_field.?invalid`,
-			out:  "no such key: invalid",
+			out:  "no such key: \"invalid\"",
 		},
 		{
 			expr: `{0: dyn(0)}[?0].?invalid`,
-			out:  "no such key: invalid",
+			out:  "no such key: \"invalid\"",
 		},
 		{
 			expr: `{true: dyn(0)}[?false].?invalid`,
 			out:  types.OptionalNone,
 		},
 		{
 			expr: `{true: dyn(0)}[?true].?invalid`,
-			out:  "no such key: invalid",
+			out:  "no such key: \"invalid\"",
 		},
 	}
 

common/types/bool.go

@@ -17,7 +17,6 @@ package types
 import (
 	"fmt"
 	"reflect"
-	"strconv"
 
 	"github.com/google/cel-go/common/types/ref"
 
@@ -93,7 +92,7 @@ func (b Bool) ConvertToNative(typeDesc reflect.Type) (any, error) {
 func (b Bool) ConvertToType(typeVal ref.Type) ref.Val {
 	switch typeVal {
 	case StringType:
-		return String(strconv.FormatBool(bool(b)))
+		return String(b.String())
 	case BoolType:
 		return b
 	case TypeType:
@@ -128,6 +127,13 @@ func (b Bool) Value() any {
 	return bool(b)
 }
 
+func (b Bool) String() string {
+	if b {
+		return "true"
+	}
+	return "false"
+}
+
 // IsBool returns whether the input ref.Val or ref.Type is equal to BoolType.
 func IsBool(elem ref.Val) bool {
 	switch v := elem.(type) {

common/types/bytes.go

@@ -19,6 +19,7 @@ import (
 	"encoding/base64"
 	"fmt"
 	"reflect"
+	"strings"
 	"unicode/utf8"
 
 	"github.com/google/cel-go/common/types/ref"
@@ -138,3 +139,17 @@ func (b Bytes) Type() ref.Type {
 func (b Bytes) Value() any {
 	return []byte(b)
 }
+
+func (b Bytes) String() string {
+	return fmt.Sprintf("b\"%s\"", bytesToOctets([]byte(b)))
+}
+
+// bytesToOctets converts byte sequences to a string using a three digit octal encoded value
+// per byte.
+func bytesToOctets(byteVal []byte) string {
+	var b strings.Builder
+	for _, c := range byteVal {
+		fmt.Fprintf(&b, "\\%03o", c)
+	}
+	return b.String()
+}

common/types/double.go

@@ -18,6 +18,8 @@ import (
 	"fmt"
 	"math"
 	"reflect"
+	"strconv"
+	"strings"
 
 	"github.com/google/cel-go/common/types/ref"
 
@@ -209,3 +211,20 @@ func (d Double) Type() ref.Type {
 func (d Double) Value() any {
 	return float64(d)
 }
+
+func (d Double) String() string {
+	if math.IsNaN(float64(d)) {
+		return "double(\"NaN\")"
+	}
+	if math.IsInf(float64(d), -1) {
+		return "double(\"-Infinity\")"
+	}
+	if math.IsInf(float64(d), 1) {
+		return "double(\"Infinity\")"
+	}
+	s := strconv.FormatFloat(float64(d), 'f', -1, 64)
+	if !strings.ContainsRune(s, '.') {
+		s = s + ".0"
+	}
+	return s
+}

common/types/duration.go

@@ -185,6 +185,10 @@ func (d Duration) Value() any {
 	return d.Duration
 }
 
+func (d Duration) String() string {
+	return fmt.Sprintf("duration(\"%ss\")", strconv.FormatFloat(d.Seconds(), 'f', -1, 64))
+}
+
 // DurationGetHours returns the duration in hours.
 func DurationGetHours(val ref.Val) ref.Val {
 	dur, ok := val.(Duration)

common/types/int.go

@@ -290,6 +290,10 @@ func (i Int) Value() any {
 	return int64(i)
 }
 
+func (i Int) String() string {
+	return strconv.FormatInt(int64(i), 10)
+}
+
 // isJSONSafe indicates whether the int is safely representable as a floating point value in JSON.
 func (i Int) isJSONSafe() bool {
 	return i >= minIntJSON && i <= maxIntJSON

common/types/json_struct_test.go

@@ -172,7 +172,7 @@ func TestJsonStructGet(t *testing.T) {
 	}
 
 	e, isError := mapVal.Get(String("third")).(*Err)
-	if !isError || e.Error() != "no such key: third" {
+	if !isError || e.Error() != "no such key: \"third\"" {
 		t.Errorf("Got %v, wanted no such key: third", e)
 	}
 }

common/types/list.go

@@ -290,7 +290,7 @@ func (l *baseList) String() string {
 	var sb strings.Builder
 	sb.WriteString("[")
 	for i := 0; i < l.size; i++ {
-		sb.WriteString(fmt.Sprintf("%v", l.get(i)))
+		sb.WriteString(fmt.Sprintf("%s", l.Get(Int(i))))
 		if i != l.size-1 {
 			sb.WriteString(", ")
 		}

common/types/list_test.go

@@ -183,7 +183,7 @@ func TestBaseListGet(t *testing.T) {
 
 func TestBaseListString(t *testing.T) {
 	l := DefaultTypeAdapter.NativeToValue([]any{1, "hello", 2.1, true, []string{"world"}})
-	want := `[1, hello, 2.1, true, [world]]`
+	want := `[1, "hello", 2.1, true, ["world"]]`
 	if fmt.Sprintf("%v", l) != want {
 		t.Errorf("l.String() got %v, wanted %v", l, want)
 	}
@@ -192,7 +192,7 @@ func TestBaseListString(t *testing.T) {
 func TestConcatListString(t *testing.T) {
 	l := DefaultTypeAdapter.NativeToValue([]any{1, "hello", 2.1, true}).(traits.Lister)
 	c := l.Add(DefaultTypeAdapter.NativeToValue([]string{"world"}))
-	want := `[1, hello, 2.1, true, world]`
+	want := `[1, "hello", 2.1, true, "world"]`
 	if fmt.Sprintf("%v", c) != want {
 		t.Errorf("c.String() got %v, wanted %v", c, want)
 	}

common/types/map.go

@@ -17,6 +17,7 @@ package types
 import (
 	"fmt"
 	"reflect"
+	"sort"
 	"strings"
 
 	"github.com/stoewer/go-strcase"
@@ -299,20 +300,35 @@ func (m *baseMap) Size() ref.Val {
 	return Int(m.size)
 }
 
+type baseMapEntry struct {
+	key string
+	val string
+}
+
 // String converts the map into a human-readable string.
 func (m *baseMap) String() string {
 	var sb strings.Builder
 	sb.WriteString("{")
 	it := m.Iterator()
-	i := 0
+	var ents []baseMapEntry
+	if s, ok := m.Size().(Int); ok {
+		ents = make([]baseMapEntry, 0, int(s))
+	}
 	for it.HasNext() == True {
 		k := it.Next()
 		v, _ := m.Find(k)
-		sb.WriteString(fmt.Sprintf("%v: %v", k, v))
-		if i != m.size-1 {
+		ents = append(ents, baseMapEntry{fmt.Sprintf("%s", k), fmt.Sprintf("%s", v)})
+	}
+	sort.SliceStable(ents, func(i, j int) bool {
+		return ents[i].key < ents[j].key
+	})
+	for i, ent := range ents {
+		if i > 0 {
 			sb.WriteString(", ")
 		}
-		i++
+		sb.WriteString(ent.key)
+		sb.WriteString(": ")
+		sb.WriteString(ent.val)
 	}
 	sb.WriteString("}")
 	return sb.String()

common/types/map_test.go

@@ -429,24 +429,24 @@ func TestDynamicMapGet(t *testing.T) {
 		t.Errorf("nestedVal.Get(1) got %v, wanted -1.0", floatVal)
 	}
 	err := mapVal.Get(String("absent"))
-	if !IsError(err) || err.(*Err).Error() != "no such key: absent" {
-		t.Errorf("mapVal.Get('absent') got %v, wanted no such key: absent.", err)
+	if !IsError(err) || err.(*Err).Error() != "no such key: \"absent\"" {
+		t.Errorf("mapVal.Get('absent') got %v, wanted no such key: \"absent\".", err)
 	}
 	err = nestedVal.Get(String("bad_key"))
-	if !IsError(err) || err.(*Err).Error() != "no such key: bad_key" {
-		t.Errorf("nestedVal.Get('bad_key') errored %v, wanted no such key: bad_key.", err)
+	if !IsError(err) || err.(*Err).Error() != "no such key: \"bad_key\"" {
+		t.Errorf("nestedVal.Get('bad_key') errored %v, wanted no such key: \"bad_key\".", err)
 	}
 	empty, ok := mapVal.Get(String("empty")).(traits.Mapper)
 	if !ok {
 		t.Fatalf("mapVal.Get('empty') got %v, wanted empty map", mapVal.Get(String("empty")))
 	}
 	err = empty.Get(String("hello"))
-	if !IsError(err) || err.(*Err).Error() != "no such key: hello" {
-		t.Errorf("empty.Get('hello') got %v, wanted no such key: hello", err)
+	if !IsError(err) || err.(*Err).Error() != "no such key: \"hello\"" {
+		t.Errorf("empty.Get('hello') got %v, wanted no such key: \"hello\"", err)
 	}
 	err = empty.Get(Double(-1.0))
-	if !IsError(err) || err.(*Err).Error() != "no such key: -1" {
-		t.Errorf("empty.Get(-1.0) got %v, wanted no such key: -1", err)
+	if !IsError(err) || err.(*Err).Error() != "no such key: -1.0" {
+		t.Errorf("empty.Get(-1.0) got %v, wanted no such key: -1.0", err)
 	}
 }
 
@@ -465,24 +465,24 @@ func TestStringIfaceMapGet(t *testing.T) {
 		t.Errorf("nestedVal.Get(1) got %v, wanted -1.0", floatVal)
 	}
 	err := mapVal.Get(String("absent"))
-	if !IsError(err) || err.(*Err).Error() != "no such key: absent" {
-		t.Errorf("mapVal.Get('absent') got %v, wanted no such key: absent.", err)
+	if !IsError(err) || err.(*Err).Error() != "no such key: \"absent\"" {
+		t.Errorf("mapVal.Get('absent') got %v, wanted no such key: \"absent\".", err)
 	}
 	err = nestedVal.Get(String("bad_key"))
-	if !IsError(err) || err.(*Err).Error() != "no such key: bad_key" {
-		t.Errorf("nestedVal.Get('bad_key') got %v, no such key: bad_key", err)
+	if !IsError(err) || err.(*Err).Error() != "no such key: \"bad_key\"" {
+		t.Errorf("nestedVal.Get('bad_key') got %v, no such key: \"bad_key\"", err)
 	}
 	empty, ok := mapVal.Get(String("empty")).(traits.Mapper)
 	if !ok {
 		t.Fatalf("mapVal.Get('empty') got %v, wanted empty map", mapVal.Get(String("empty")))
 	}
 	err = empty.Get(String("hello"))
-	if !IsError(err) || err.(*Err).Error() != "no such key: hello" {
-		t.Errorf("empty.Get('hello') got %v, wanted no such key: hello", err)
+	if !IsError(err) || err.(*Err).Error() != "no such key: \"hello\"" {
+		t.Errorf("empty.Get('hello') got %v, wanted no such key: \"hello\"", err)
 	}
 	err = empty.Get(Double(-1.0))
-	if !IsError(err) || err.(*Err).Error() != "no such key: -1" {
-		t.Errorf("empty.Get(-1.0) got %v, wanted no such key: -1", err)
+	if !IsError(err) || err.(*Err).Error() != "no such key: -1.0" {
+		t.Errorf("empty.Get(-1.0) got %v, wanted no such key: -1.0", err)
 	}
 }
 
@@ -520,24 +520,24 @@ func TestRefValMapGet(t *testing.T) {
 		t.Errorf("nestedVal.Get(1) got %v, wanted -1.0", floatVal)
 	}
 	err := mapVal.Get(String("absent"))
-	if !IsError(err) || err.(*Err).Error() != "no such key: absent" {
+	if !IsError(err) || err.(*Err).Error() != "no such key: \"absent\"" {
 		t.Errorf("mapVal.Get('absent') got %v, wanted no such key: absent.", err)
 	}
 	err = nestedVal.Get(String("bad_key"))
-	if !IsError(err) || err.(*Err).Error() != "no such key: bad_key" {
-		t.Errorf("nestedVal.Get('bad_key') got %v, wanted no such key: bad_key.", err)
+	if !IsError(err) || err.(*Err).Error() != "no such key: \"bad_key\"" {
+		t.Errorf("nestedVal.Get('bad_key') got %v, wanted no such key: \"bad_key\".", err)
 	}
 	empty, ok := mapVal.Get(String("empty")).(traits.Mapper)
 	if !ok {
 		t.Fatalf("mapVal.Get('empty') got %v, wanted empty map", mapVal.Get(String("empty")))
 	}
 	err = empty.Get(String("hello"))
-	if !IsError(err) || err.(*Err).Error() != "no such key: hello" {
-		t.Errorf("empty.Get('hello') got %v, wanted no such key: hello", err)
+	if !IsError(err) || err.(*Err).Error() != "no such key: \"hello\"" {
+		t.Errorf("empty.Get('hello') got %v, wanted no such key: \"hello\"", err)
 	}
 	err = empty.Get(Double(-1.0))
-	if !IsError(err) || err.(*Err).Error() != "no such key: -1" {
-		t.Errorf("empty.Get(-1.0) got %v, wanted no such key: -1", err)
+	if !IsError(err) || err.(*Err).Error() != "no such key: -1.0" {
+		t.Errorf("empty.Get(-1.0) got %v, wanted no such key: -1.0", err)
 	}
 }
 
@@ -842,7 +842,7 @@ func TestProtoMapString(t *testing.T) {
 	}
 	reg := newTestRegistry(t)
 	m := reg.NativeToValue(strMap)
-	want := `{hello: world}`
+	want := `{"hello": "world"}`
 	if fmt.Sprintf("%v", m) != want {
 		t.Errorf("map.String() got %v, wanted %v", m, want)
 	}

common/types/null.go

@@ -117,3 +117,7 @@ func (n Null) Type() ref.Type {
 func (n Null) Value() any {
 	return structpb.NullValue_NULL_VALUE
 }
+
+func (n Null) String() string {
+	return "null"
+}