libgo: update to Go 1.13beta1 release

    
    Reviewed-on: https://go-review.googlesource.com/c/gofrontend/+/193497

From-SVN: r275473

3 files changed, 222 insertions, 141 deletions

diff --git a/libgo/go/syscall/js/js.go b/libgo/go/syscall/js/js.go
index 0893db0..7300d2c 100644
--- a/libgo/go/syscall/js/js.go
+++ b/libgo/go/syscall/js/js.go
@@ -79,8 +79,7 @@ var (
 	valueTrue      = predefValue(3)
 	valueFalse     = predefValue(4)
 	valueGlobal    = predefValue(5)
-	memory         = predefValue(6) // WebAssembly linear memory
-	jsGo           = predefValue(7) // instance of the Go class in JavaScript
+	jsGo           = predefValue(6) // instance of the Go class in JavaScript
 
 	objectConstructor = valueGlobal.Get("Object")
 	arrayConstructor  = valueGlobal.Get("Array")
@@ -106,7 +105,6 @@ func Global() Value {
 //  | Go                     | JavaScript             |
 //  | ---------------------- | ---------------------- |
 //  | js.Value               | [its value]            |
-//  | js.TypedArray          | typed array            |
 //  | js.Func                | function               |
 //  | nil                    | null                   |
 //  | bool                   | boolean                |
@@ -216,6 +214,10 @@ func (t Type) String() string {
 	}
 }
 
+func (t Type) isObject() bool {
+	return t == TypeObject || t == TypeFunction
+}
+
 // Type returns the JavaScript type of the value v. It is similar to JavaScript's typeof operator,
 // except that it returns TypeNull instead of TypeObject for null.
 func (v Value) Type() Type {
@@ -244,28 +246,44 @@ func (v Value) Type() Type {
 }
 
 // Get returns the JavaScript property p of value v.
+// It panics if v is not a JavaScript object.
 func (v Value) Get(p string) Value {
+	if vType := v.Type(); !vType.isObject() {
+		panic(&ValueError{"Value.Get", vType})
+	}
 	return makeValue(valueGet(v.ref, p))
 }
 
 func valueGet(v ref, p string) ref
 
 // Set sets the JavaScript property p of value v to ValueOf(x).
+// It panics if v is not a JavaScript object.
 func (v Value) Set(p string, x interface{}) {
+	if vType := v.Type(); !vType.isObject() {
+		panic(&ValueError{"Value.Set", vType})
+	}
 	valueSet(v.ref, p, ValueOf(x).ref)
 }
 
 func valueSet(v ref, p string, x ref)
 
 // Index returns JavaScript index i of value v.
+// It panics if v is not a JavaScript object.
 func (v Value) Index(i int) Value {
+	if vType := v.Type(); !vType.isObject() {
+		panic(&ValueError{"Value.Index", vType})
+	}
 	return makeValue(valueIndex(v.ref, i))
 }
 
 func valueIndex(v ref, i int) ref
 
 // SetIndex sets the JavaScript index i of value v to ValueOf(x).
+// It panics if v is not a JavaScript object.
 func (v Value) SetIndex(i int, x interface{}) {
+	if vType := v.Type(); !vType.isObject() {
+		panic(&ValueError{"Value.SetIndex", vType})
+	}
 	valueSetIndex(v.ref, i, ValueOf(x).ref)
 }
 
@@ -280,7 +298,11 @@ func makeArgs(args []interface{}) []ref {
 }
 
 // Length returns the JavaScript property "length" of v.
+// It panics if v is not a JavaScript object.
 func (v Value) Length() int {
+	if vType := v.Type(); !vType.isObject() {
+		panic(&ValueError{"Value.SetIndex", vType})
+	}
 	return valueLength(v.ref)
 }
 
@@ -292,7 +314,7 @@ func valueLength(v ref) int
 func (v Value) Call(m string, args ...interface{}) Value {
 	res, ok := valueCall(v.ref, m, makeArgs(args))
 	if !ok {
-		if vType := v.Type(); vType != TypeObject && vType != TypeFunction { // check here to avoid overhead in success case
+		if vType := v.Type(); !vType.isObject() { // check here to avoid overhead in success case
 			panic(&ValueError{"Value.Call", vType})
 		}
 		if propType := v.Get(m).Type(); propType != TypeFunction {
@@ -306,7 +328,7 @@ func (v Value) Call(m string, args ...interface{}) Value {
 func valueCall(v ref, m string, args []ref) (ref, bool)
 
 // Invoke does a JavaScript call of the value v with the given arguments.
-// It panics if v is not a function.
+// It panics if v is not a JavaScript function.
 // The arguments get mapped to JavaScript values according to the ValueOf function.
 func (v Value) Invoke(args ...interface{}) Value {
 	res, ok := valueInvoke(v.ref, makeArgs(args))
@@ -322,11 +344,14 @@ func (v Value) Invoke(args ...interface{}) Value {
 func valueInvoke(v ref, args []ref) (ref, bool)
 
 // New uses JavaScript's "new" operator with value v as constructor and the given arguments.
-// It panics if v is not a function.
+// It panics if v is not a JavaScript function.
 // The arguments get mapped to JavaScript values according to the ValueOf function.
 func (v Value) New(args ...interface{}) Value {
 	res, ok := valueNew(v.ref, makeArgs(args))
 	if !ok {
+		if vType := v.Type(); vType != TypeFunction { // check here to avoid overhead in success case
+			panic(&ValueError{"Value.Invoke", vType})
+		}
 		panic(Error{makeValue(res)})
 	}
 	return makeValue(res)
@@ -350,17 +375,20 @@ func (v Value) float(method string) float64 {
 	return *(*float64)(unsafe.Pointer(&v.ref))
 }
 
-// Float returns the value v as a float64. It panics if v is not a JavaScript number.
+// Float returns the value v as a float64.
+// It panics if v is not a JavaScript number.
 func (v Value) Float() float64 {
 	return v.float("Value.Float")
 }
 
-// Int returns the value v truncated to an int. It panics if v is not a JavaScript number.
+// Int returns the value v truncated to an int.
+// It panics if v is not a JavaScript number.
 func (v Value) Int() int {
 	return int(v.float("Value.Int"))
 }
 
-// Bool returns the value v as a bool. It panics if v is not a JavaScript boolean.
+// Bool returns the value v as a bool.
+// It panics if v is not a JavaScript boolean.
 func (v Value) Bool() bool {
 	switch v.ref {
 	case valueTrue.ref:
@@ -392,9 +420,35 @@ func (v Value) Truthy() bool {
 	}
 }
 
-// String returns the value v converted to string according to JavaScript type conversions.
+// String returns the value v as a string.
+// String is a special case because of Go's String method convention. Unlike the other getters,
+// it does not panic if v's Type is not TypeString. Instead, it returns a string of the form "<T>"
+// or "<T: V>" where T is v's type and V is a string representation of v's value.
 func (v Value) String() string {
-	str, length := valuePrepareString(v.ref)
+	switch v.Type() {
+	case TypeString:
+		return jsString(v.ref)
+	case TypeUndefined:
+		return "<undefined>"
+	case TypeNull:
+		return "<null>"
+	case TypeBoolean:
+		return "<boolean: " + jsString(v.ref) + ">"
+	case TypeNumber:
+		return "<number: " + jsString(v.ref) + ">"
+	case TypeSymbol:
+		return "<symbol>"
+	case TypeObject:
+		return "<object>"
+	case TypeFunction:
+		return "<function>"
+	default:
+		panic("bad type")
+	}
+}
+
+func jsString(v ref) string {
+	str, length := valuePrepareString(v)
 	b := make([]byte, length)
 	valueLoadString(str, b)
 	return string(b)
@@ -422,3 +476,29 @@ type ValueError struct {
 func (e *ValueError) Error() string {
 	return "syscall/js: call of " + e.Method + " on " + e.Type.String()
 }
+
+// CopyBytesToGo copies bytes from the Uint8Array src to dst.
+// It returns the number of bytes copied, which will be the minimum of the lengths of src and dst.
+// CopyBytesToGo panics if src is not an Uint8Array.
+func CopyBytesToGo(dst []byte, src Value) int {
+	n, ok := copyBytesToGo(dst, src.ref)
+	if !ok {
+		panic("syscall/js: CopyBytesToGo: expected src to be an Uint8Array")
+	}
+	return n
+}
+
+func copyBytesToGo(dst []byte, src ref) (int, bool)
+
+// CopyBytesToJS copies bytes from src to the Uint8Array dst.
+// It returns the number of bytes copied, which will be the minimum of the lengths of src and dst.
+// CopyBytesToJS panics if dst is not an Uint8Array.
+func CopyBytesToJS(dst Value, src []byte) int {
+	n, ok := copyBytesToJS(dst.ref, src)
+	if !ok {
+		panic("syscall/js: CopyBytesToJS: expected dst to be an Uint8Array")
+	}
+	return n
+}
+
+func copyBytesToJS(dst ref, src []byte) (int, bool)
diff --git a/libgo/go/syscall/js/js_test.go b/libgo/go/syscall/js/js_test.go
index c14d2cc..7a1e346 100644
--- a/libgo/go/syscall/js/js_test.go
+++ b/libgo/go/syscall/js/js_test.go
@@ -72,10 +72,26 @@ func TestString(t *testing.T) {
 		t.Errorf("same value not equal")
 	}
 
-	wantInt := "42"
-	o = dummys.Get("someInt")
-	if got := o.String(); got != wantInt {
-		t.Errorf("got %#v, want %#v", got, wantInt)
+	if got, want := js.Undefined().String(), "<undefined>"; got != want {
+		t.Errorf("got %#v, want %#v", got, want)
+	}
+	if got, want := js.Null().String(), "<null>"; got != want {
+		t.Errorf("got %#v, want %#v", got, want)
+	}
+	if got, want := js.ValueOf(true).String(), "<boolean: true>"; got != want {
+		t.Errorf("got %#v, want %#v", got, want)
+	}
+	if got, want := js.ValueOf(42.5).String(), "<number: 42.5>"; got != want {
+		t.Errorf("got %#v, want %#v", got, want)
+	}
+	if got, want := js.Global().Call("Symbol").String(), "<symbol>"; got != want {
+		t.Errorf("got %#v, want %#v", got, want)
+	}
+	if got, want := js.Global().String(), "<object>"; got != want {
+		t.Errorf("got %#v, want %#v", got, want)
+	}
+	if got, want := js.Global().Get("setTimeout").String(), "<function>"; got != want {
+		t.Errorf("got %#v, want %#v", got, want)
 	}
 }
 
@@ -151,28 +167,6 @@ func TestFrozenObject(t *testing.T) {
 	}
 }
 
-func TestTypedArrayOf(t *testing.T) {
-	testTypedArrayOf(t, "[]int8", []int8{0, -42, 0}, -42)
-	testTypedArrayOf(t, "[]int16", []int16{0, -42, 0}, -42)
-	testTypedArrayOf(t, "[]int32", []int32{0, -42, 0}, -42)
-	testTypedArrayOf(t, "[]uint8", []uint8{0, 42, 0}, 42)
-	testTypedArrayOf(t, "[]uint16", []uint16{0, 42, 0}, 42)
-	testTypedArrayOf(t, "[]uint32", []uint32{0, 42, 0}, 42)
-	testTypedArrayOf(t, "[]float32", []float32{0, -42.5, 0}, -42.5)
-	testTypedArrayOf(t, "[]float64", []float64{0, -42.5, 0}, -42.5)
-}
-
-func testTypedArrayOf(t *testing.T, name string, slice interface{}, want float64) {
-	t.Run(name, func(t *testing.T) {
-		a := js.TypedArrayOf(slice)
-		got := a.Index(1).Float()
-		a.Release()
-		if got != want {
-			t.Errorf("got %#v, want %#v", got, want)
-		}
-	})
-}
-
 func TestNaN(t *testing.T) {
 	want := js.ValueOf(math.NaN())
 	got := dummys.Get("NaN")
@@ -202,10 +196,30 @@ func TestLength(t *testing.T) {
 	}
 }
 
+func TestGet(t *testing.T) {
+	// positive cases get tested per type
+
+	expectValueError(t, func() {
+		dummys.Get("zero").Get("badField")
+	})
+}
+
+func TestSet(t *testing.T) {
+	// positive cases get tested per type
+
+	expectValueError(t, func() {
+		dummys.Get("zero").Set("badField", 42)
+	})
+}
+
 func TestIndex(t *testing.T) {
 	if got := dummys.Get("someArray").Index(1).Int(); got != 42 {
 		t.Errorf("got %#v, want %#v", got, 42)
 	}
+
+	expectValueError(t, func() {
+		dummys.Get("zero").Index(1)
+	})
 }
 
 func TestSetIndex(t *testing.T) {
@@ -213,6 +227,10 @@ func TestSetIndex(t *testing.T) {
 	if got := dummys.Get("someArray").Index(2).Int(); got != 99 {
 		t.Errorf("got %#v, want %#v", got, 99)
 	}
+
+	expectValueError(t, func() {
+		dummys.Get("zero").SetIndex(2, 99)
+	})
 }
 
 func TestCall(t *testing.T) {
@@ -223,6 +241,13 @@ func TestCall(t *testing.T) {
 	if got := dummys.Call("add", js.Global().Call("eval", "40"), 2).Int(); got != 42 {
 		t.Errorf("got %#v, want %#v", got, 42)
 	}
+
+	expectPanic(t, func() {
+		dummys.Call("zero")
+	})
+	expectValueError(t, func() {
+		dummys.Get("zero").Call("badMethod")
+	})
 }
 
 func TestInvoke(t *testing.T) {
@@ -230,12 +255,20 @@ func TestInvoke(t *testing.T) {
 	if got := dummys.Get("add").Invoke(i, 2).Int(); got != 42 {
 		t.Errorf("got %#v, want %#v", got, 42)
 	}
+
+	expectValueError(t, func() {
+		dummys.Get("zero").Invoke()
+	})
 }
 
 func TestNew(t *testing.T) {
 	if got := js.Global().Get("Array").New(42).Length(); got != 42 {
 		t.Errorf("got %#v, want %#v", got, 42)
 	}
+
+	expectValueError(t, func() {
+		dummys.Get("zero").New()
+	})
 }
 
 func TestInstanceOf(t *testing.T) {
@@ -379,3 +412,75 @@ func TestTruthy(t *testing.T) {
 		t.Errorf("got %#v, want %#v", got, want)
 	}
 }
+
+func expectValueError(t *testing.T, fn func()) {
+	defer func() {
+		err := recover()
+		if _, ok := err.(*js.ValueError); !ok {
+			t.Errorf("expected *js.ValueError, got %T", err)
+		}
+	}()
+	fn()
+}
+
+func expectPanic(t *testing.T, fn func()) {
+	defer func() {
+		err := recover()
+		if err == nil {
+			t.Errorf("expected panic")
+		}
+	}()
+	fn()
+}
+
+var copyTests = []struct {
+	srcLen  int
+	dstLen  int
+	copyLen int
+}{
+	{5, 3, 3},
+	{3, 5, 3},
+	{0, 0, 0},
+}
+
+func TestCopyBytesToGo(t *testing.T) {
+	for _, tt := range copyTests {
+		t.Run(fmt.Sprintf("%d-to-%d", tt.srcLen, tt.dstLen), func(t *testing.T) {
+			src := js.Global().Get("Uint8Array").New(tt.srcLen)
+			if tt.srcLen >= 2 {
+				src.SetIndex(1, 42)
+			}
+			dst := make([]byte, tt.dstLen)
+
+			if got, want := js.CopyBytesToGo(dst, src), tt.copyLen; got != want {
+				t.Errorf("copied %d, want %d", got, want)
+			}
+			if tt.dstLen >= 2 {
+				if got, want := int(dst[1]), 42; got != want {
+					t.Errorf("got %d, want %d", got, want)
+				}
+			}
+		})
+	}
+}
+
+func TestCopyBytesToJS(t *testing.T) {
+	for _, tt := range copyTests {
+		t.Run(fmt.Sprintf("%d-to-%d", tt.srcLen, tt.dstLen), func(t *testing.T) {
+			src := make([]byte, tt.srcLen)
+			if tt.srcLen >= 2 {
+				src[1] = 42
+			}
+			dst := js.Global().Get("Uint8Array").New(tt.dstLen)
+
+			if got, want := js.CopyBytesToJS(dst, src), tt.copyLen; got != want {
+				t.Errorf("copied %d, want %d", got, want)
+			}
+			if tt.dstLen >= 2 {
+				if got, want := dst.Index(1).Int(), 42; got != want {
+					t.Errorf("got %d, want %d", got, want)
+				}
+			}
+		})
+	}
+}
diff --git a/libgo/go/syscall/js/typedarray.go b/libgo/go/syscall/js/typedarray.go
deleted file mode 100644
index aa56cf6..0000000
--- a/libgo/go/syscall/js/typedarray.go
+++ /dev/null
@@ -1,104 +0,0 @@
-// Copyright 2018 The Go Authors. All rights reserved.
-// Use of this source code is governed by a BSD-style
-// license that can be found in the LICENSE file.
-
-// +build js,wasm
-
-package js
-
-import (
-	"sync"
-	"unsafe"
-)
-
-var (
-	int8Array    = Global().Get("Int8Array")
-	int16Array   = Global().Get("Int16Array")
-	int32Array   = Global().Get("Int32Array")
-	uint8Array   = Global().Get("Uint8Array")
-	uint16Array  = Global().Get("Uint16Array")
-	uint32Array  = Global().Get("Uint32Array")
-	float32Array = Global().Get("Float32Array")
-	float64Array = Global().Get("Float64Array")
-)
-
-var _ Wrapper = TypedArray{} // TypedArray must implement Wrapper
-
-// TypedArray represents a JavaScript typed array.
-type TypedArray struct {
-	Value
-}
-
-// Release frees up resources allocated for the typed array.
-// The typed array and its buffer must not be accessed after calling Release.
-func (a TypedArray) Release() {
-	openTypedArraysMutex.Lock()
-	delete(openTypedArrays, a)
-	openTypedArraysMutex.Unlock()
-}
-
-var (
-	openTypedArraysMutex sync.Mutex
-	openTypedArrays      = make(map[TypedArray]interface{})
-)
-
-// TypedArrayOf returns a JavaScript typed array backed by the slice's underlying array.
-//
-// The supported types are []int8, []int16, []int32, []uint8, []uint16, []uint32, []float32 and []float64.
-// Passing an unsupported value causes a panic.
-//
-// TypedArray.Release must be called to free up resources when the typed array will not be used any more.
-func TypedArrayOf(slice interface{}) TypedArray {
-	a := TypedArray{typedArrayOf(slice)}
-	openTypedArraysMutex.Lock()
-	openTypedArrays[a] = slice
-	openTypedArraysMutex.Unlock()
-	return a
-}
-
-func typedArrayOf(slice interface{}) Value {
-	switch slice := slice.(type) {
-	case []int8:
-		if len(slice) == 0 {
-			return int8Array.New(memory.Get("buffer"), 0, 0)
-		}
-		return int8Array.New(memory.Get("buffer"), unsafe.Pointer(&slice[0]), len(slice))
-	case []int16:
-		if len(slice) == 0 {
-			return int16Array.New(memory.Get("buffer"), 0, 0)
-		}
-		return int16Array.New(memory.Get("buffer"), unsafe.Pointer(&slice[0]), len(slice))
-	case []int32:
-		if len(slice) == 0 {
-			return int32Array.New(memory.Get("buffer"), 0, 0)
-		}
-		return int32Array.New(memory.Get("buffer"), unsafe.Pointer(&slice[0]), len(slice))
-	case []uint8:
-		if len(slice) == 0 {
-			return uint8Array.New(memory.Get("buffer"), 0, 0)
-		}
-		return uint8Array.New(memory.Get("buffer"), unsafe.Pointer(&slice[0]), len(slice))
-	case []uint16:
-		if len(slice) == 0 {
-			return uint16Array.New(memory.Get("buffer"), 0, 0)
-		}
-		return uint16Array.New(memory.Get("buffer"), unsafe.Pointer(&slice[0]), len(slice))
-	case []uint32:
-		if len(slice) == 0 {
-			return uint32Array.New(memory.Get("buffer"), 0, 0)
-		}
-		return uint32Array.New(memory.Get("buffer"), unsafe.Pointer(&slice[0]), len(slice))
-	case []float32:
-		if len(slice) == 0 {
-			return float32Array.New(memory.Get("buffer"), 0, 0)
-		}
-		return float32Array.New(memory.Get("buffer"), unsafe.Pointer(&slice[0]), len(slice))
-	case []float64:
-		if len(slice) == 0 {
-			return float64Array.New(memory.Get("buffer"), 0, 0)
-		}
-		return float64Array.New(memory.Get("buffer"), unsafe.Pointer(&slice[0]), len(slice))
-	default:
-		panic("TypedArrayOf: not a supported slice")
-	}
-}