src/pkg/reflect/all_test.go

// Copyright 2009 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.

package reflect

import (
	"io";
	"os";
	"reflect";
	"testing";
	"unsafe";
)

type integer int
type T struct { a int; b float64; c string; d *int }

type pair struct {
	i interface{};
	s string;
}

func isDigit(c uint8) bool {
	return '0' <= c && c <= '9'
}

func assert(t *testing.T, s, want string) {
	if s != want {
		t.Errorf("have %#q want %#q", s, want);
	}
}

func typestring(i interface{}) string {
	return Typeof(i).String();
}

var typeTests = []pair {
	pair { struct { x int }{}, "int" },
	pair { struct { x int8 }{}, "int8" },
	pair { struct { x int16 }{}, "int16" },
	pair { struct { x int32 }{}, "int32" },
	pair { struct { x int64 }{}, "int64" },
	pair { struct { x uint }{}, "uint" },
	pair { struct { x uint8 }{}, "uint8" },
	pair { struct { x uint16 }{}, "uint16" },
	pair { struct { x uint32 }{}, "uint32" },
	pair { struct { x uint64 }{}, "uint64" },
	pair { struct { x float }{}, "float" },
	pair { struct { x float32 }{}, "float32" },
	pair { struct { x float64 }{}, "float64" },
	pair { struct { x int8 }{}, "int8" },
	pair { struct { x (**int8) }{}, "**int8" },
	pair { struct { x (**reflect.integer) }{}, "**reflect.integer" },
	pair { struct { x ([32]int32) }{}, "[32]int32" },
	pair { struct { x ([]int8) }{}, "[]int8" },
	pair { struct { x (map[string]int32) }{}, "map[string] int32" },
	pair { struct { x (chan<-string) }{}, "chan<- string" },
	pair { struct { x struct {c chan *int32; d float32} }{}, "struct { c chan *int32; d float32 }" },
	pair { struct { x (func(a int8, b int32)) }{}, "func(int8, int32)" },
	pair { struct { x struct {c func(chan *reflect.integer, *int8)} }{}, "struct { c func(chan *reflect.integer, *int8) }" },
	pair { struct { x struct {a int8; b int32} }{}, "struct { a int8; b int32 }" },
	pair { struct { x struct {a int8; b int8; b int32} }{}, "struct { a int8; b int8; b int32 }" },
	pair { struct { x struct {a int8; b int8; c int8; b int32} }{}, "struct { a int8; b int8; c int8; b int32 }" },
	pair { struct { x struct {a int8; b int8; c int8; d int8; b int32} }{}, "struct { a int8; b int8; c int8; d int8; b int32 }" },
	pair { struct { x struct {a int8; b int8; c int8; d int8; e int8; b int32} }{}, "struct { a int8; b int8; c int8; d int8; e int8; b int32 }" },
	pair { struct { x struct {a int8 "hi there"; } }{}, `struct { a int8 "hi there" }` },
	pair { struct { x struct {a int8 "hi \x00there\t\n\"\\"; } }{}, `struct { a int8 "hi \x00there\t\n\"\\" }` },
	pair { struct { x struct {f func(args ...)} }{}, "struct { f func(...) }" },
	pair { struct { x (interface { a(func(func(int)(int))(func(func(int))(int))); b() }) }{}, "interface { a (func(func(int) (int)) (func(func(int)) (int))); b () }" },
}

var valueTests = []pair {
	pair { (int8)(0), "8" },
	pair { (int16)(0), "16" },
	pair { (int32)(0), "32" },
	pair { (int64)(0), "64" },
	pair { (uint8)(0), "8" },
	pair { (uint16)(0), "16" },
	pair { (uint32)(0), "32" },
	pair { (uint64)(0), "64" },
	pair { (float32)(0), "32.1" },
	pair { (float64)(0), "64.2" },
	pair { (string)(""), "stringy cheese" },
	pair { (bool)(false), "true" },
	pair { (*int8)(nil), "*int8(0)" },
	pair { (**int8)(nil), "**int8(0)" },
	pair { ([5]int32){}, "[5]int32{0, 0, 0, 0, 0}" },
	pair { (**reflect.integer)(nil), "**reflect.integer(0)" },
	pair { (map[string]int32)(nil), "map[string] int32{<can't iterate on maps>}" },
	pair { (chan<-string)(nil), "chan<- string" },
	pair { (struct {c chan *int32; d float32}){}, "struct { c chan *int32; d float32 }{chan *int32, 0}" },
	pair { (func(a int8, b int32))(nil), "func(int8, int32)(0)" },
	pair { (struct {c func(chan *reflect.integer, *int8)}){}, "struct { c func(chan *reflect.integer, *int8) }{func(chan *reflect.integer, *int8)(0)}" },
	pair { (struct {a int8; b int32}){}, "struct { a int8; b int32 }{0, 0}" },
	pair { (struct {a int8; b int8; b int32}){}, "struct { a int8; b int8; b int32 }{0, 0, 0}" },
}

func testType(t *testing.T, i int, typ Type, want string) {
	s := typ.String();
	if s != want {
		t.Errorf("#%d: have %#q, want %#q", i, s, want);
	}
}

func TestTypes(t *testing.T) {
	for i, tt := range typeTests {
		testType(t, i, NewValue(tt.i).(*StructValue).Field(0).Type(), tt.s);
	}
}

func TestValue(t *testing.T) {
	for i, tt := range valueTests {
		v := NewValue(tt.i);
		switch v := v.(type) {
		case *reflect.IntValue:
			v.Set(132);
		case *reflect.Int8Value:
			v.Set(8);
		case *reflect.Int16Value:
			v.Set(16);
		case *reflect.Int32Value:
			v.Set(32);
		case *reflect.Int64Value:
			v.Set(64);
		case *reflect.UintValue:
			v.Set(132);
		case *reflect.Uint8Value:
			v.Set(8);
		case *reflect.Uint16Value:
			v.Set(16);
		case *reflect.Uint32Value:
			v.Set(32);
		case *reflect.Uint64Value:
			v.Set(64);
		case *reflect.FloatValue:
			v.Set(3200.0);
		case *reflect.Float32Value:
			v.Set(32.1);
		case *reflect.Float64Value:
			v.Set(64.2);
		case *reflect.StringValue:
			v.Set("stringy cheese");
		case *reflect.BoolValue:
			v.Set(true);
		}
		s := valueToString(v);
		if s != tt.s {
			t.Errorf("#%d: have %#q, want %#q", i, s, tt.s);
		}
	}
}

var _i = 7;

var valueToStringTests = []pair {
	pair { 123, "123" },
	pair { 123.4, "123.4" },
	pair { byte(123), "123" },
	pair { "abc", "abc" },
	pair { T{123, 456.75, "hello", &_i}, "reflect.T{123, 456.75, hello, *int(&7)}" },
	pair { new(chan *T), "*chan *reflect.T(&chan *reflect.T)" },
	pair { [10]int{1,2,3,4,5,6,7,8,9,10}, "[10]int{1, 2, 3, 4, 5, 6, 7, 8, 9, 10}" },
	pair { &[10]int{1,2,3,4,5,6,7,8,9,10}, "*[10]int(&[10]int{1, 2, 3, 4, 5, 6, 7, 8, 9, 10})" },
	pair { []int{1,2,3,4,5,6,7,8,9,10}, "[]int{1, 2, 3, 4, 5, 6, 7, 8, 9, 10}" },
	pair { &[]int{1,2,3,4,5,6,7,8,9,10}, "*[]int(&[]int{1, 2, 3, 4, 5, 6, 7, 8, 9, 10})" }
}

func TestValueToString(t *testing.T) {
	for i, test := range valueToStringTests {
		s := valueToString(NewValue(test.i));
		if s != test.s {
			t.Errorf("#%d: have %#q, want %#q", i, s, test.s);
		}
	}
}

func TestArrayElemSet(t *testing.T) {
	v := NewValue([10]int{1,2,3,4,5,6,7,8,9,10});
	v.(*ArrayValue).Elem(4).(*IntValue).Set(123);
	s := valueToString(v);
	const want = "[10]int{1, 2, 3, 4, 123, 6, 7, 8, 9, 10}";
	if s != want {
		t.Errorf("[10]int: have %#q want %#q", s, want);
	}

	v = NewValue([]int{1,2,3,4,5,6,7,8,9,10});
	v.(*SliceValue).Elem(4).(*IntValue).Set(123);
	s = valueToString(v);
	const want1 = "[]int{1, 2, 3, 4, 123, 6, 7, 8, 9, 10}";
	if s != want1 {
		t.Errorf("[]int: have %#q want %#q", s, want1);
	}
}

func TestPtrPointTo(t *testing.T) {
	var ip *int32;
	var i int32 = 1234;
	vip := NewValue(&ip);
	vi := NewValue(i);
	vip.(*PtrValue).Elem().(*PtrValue).PointTo(vi);
	if *ip != 1234 {
		t.Errorf("got %d, want 1234", *ip);
	}
}

func TestAll(t *testing.T) {	// TODO(r): wrap up better
	testType(t, 1, Typeof((int8)(0)), "int8");
	testType(t, 2, Typeof((*int8)(nil)).(*PtrType).Elem(), "int8");

	typ := Typeof((*struct{c chan *int32; d float32})(nil));
	testType(t, 3, typ, "*struct { c chan *int32; d float32 }");
	etyp := typ.(*PtrType).Elem();
	testType(t, 4, etyp, "struct { c chan *int32; d float32 }");
	styp := etyp.(*StructType);
	f := styp.Field(0);
	testType(t, 5, f.Type, "chan *int32");
	f = styp.Field(1);
	testType(t, 6, f.Type, "float32");

	typ = Typeof(([32]int32)(nil));
	testType(t, 7, typ, "[32]int32");
	testType(t, 8, typ.(*ArrayType).Elem(), "int32");

	typ = Typeof((map[string]*int32)(nil));
	testType(t, 9, typ, "map[string] *int32");
	mtyp := typ.(*MapType);
	testType(t, 10, mtyp.Key(), "string");
	testType(t, 11, mtyp.Elem(), "*int32");

	typ = Typeof((chan<-string)(nil));
	testType(t, 12, typ, "chan<- string");
	testType(t, 13, typ.(*ChanType).Elem(), "string");

	// make sure tag strings are not part of element type
	typ = Typeof(struct{d []uint32 "TAG"}{}).(*StructType).Field(0).Type;
	testType(t, 14, typ, "[]uint32");
}

func TestInterfaceGet(t *testing.T) {
	var inter struct { e interface{ } };
	inter.e = 123.456;
	v1 := NewValue(&inter);
	v2 := v1.(*PtrValue).Elem().(*StructValue).Field(0);
	assert(t, v2.Type().String(), "interface { }");
	i2 := v2.(*InterfaceValue).Interface();
	v3 := NewValue(i2);
	assert(t, v3.Type().String(), "float");
}

func TestInterfaceValue(t *testing.T) {
	var inter struct { e interface{ } };
	inter.e = 123.456;
	v1 := NewValue(&inter);
	v2 := v1.(*PtrValue).Elem().(*StructValue).Field(0);
	assert(t, v2.Type().String(), "interface { }");
	v3 := v2.(*InterfaceValue).Elem();
	assert(t, v3.Type().String(), "float");

	i3 := v2.Interface();
	if f, ok := i3.(float); !ok {
		t.Error("v2.Interface() did not return float, got ", Typeof(i3));
	}
}

func TestFunctionValue(t *testing.T) {
	v := NewValue(func() {});
	if v.Interface() != v.Interface() {
		t.Fatalf("TestFunction != itself");
	}
	assert(t, v.Type().String(), "func()");
}

func TestCopyArray(t *testing.T) {
	a := []int{ 1, 2, 3, 4, 10, 9, 8, 7 };
	b := []int{ 11, 22, 33, 44, 1010, 99, 88, 77, 66, 55, 44 };
	c := []int{ 11, 22, 33, 44, 1010, 99, 88, 77, 66, 55, 44 };
	va := NewValue(&a);
	vb := NewValue(&b);
	for i := 0; i < len(b); i++ {
		if b[i] != c[i] {
			t.Fatalf("b != c before test");
		}
	}
	aa := va.(*PtrValue).Elem().(*SliceValue);
	ab := vb.(*PtrValue).Elem().(*SliceValue);
	for tocopy := 1; tocopy <= 7; tocopy++ {
		aa.SetLen(tocopy);
		ArrayCopy(ab, aa);
		aa.SetLen(8);
		for i := 0; i < tocopy; i++ {
			if a[i] != b[i] {
				t.Errorf("(i) tocopy=%d a[%d]=%d, b[%d]=%d",
					tocopy, i, a[i], i, b[i]);
			}
		}
		for i := tocopy; i < len(b); i++ {
			if b[i] != c[i] {
				if i < len(a) {
					t.Errorf("(ii) tocopy=%d a[%d]=%d, b[%d]=%d, c[%d]=%d",
						tocopy, i, a[i], i, b[i], i, c[i]);
				} else {
					t.Errorf("(iii) tocopy=%d b[%d]=%d, c[%d]=%d",
						tocopy, i, b[i], i, c[i]);
				}
			} else {
				t.Logf("tocopy=%d elem %d is okay\n", tocopy, i);
			}
		}
	}
}

func TestBigUnnamedStruct(t *testing.T) {
	b := struct{a,b,c,d int64}{1, 2, 3, 4};
	v := NewValue(b);
	b1 := v.Interface().(struct{a,b,c,d int64});
	if b1.a != b.a || b1.b != b.b || b1.c != b.c || b1.d != b.d {
		t.Errorf("NewValue(%v).Interface().(*Big) = %v", b, b1);
	}
}

type big struct {
	a, b, c, d, e int64
}
func TestBigStruct(t *testing.T) {
	b := big{1, 2, 3, 4, 5};
	v := NewValue(b);
	b1 := v.Interface().(big);
	if b1.a != b.a || b1.b != b.b || b1.c != b.c || b1.d != b.d || b1.e != b.e {
		t.Errorf("NewValue(%v).Interface().(big) = %v", b, b1);
	}
}

type Basic struct {
	x int;
	y float32
}

type NotBasic Basic

type Recursive struct {
	x int;
	r *Recursive
}

type Complex struct {
	a int;
	b [3]*Complex;
	c *string;
	d map[float]float
}

type DeepEqualTest struct {
	a, b interface{};
	eq bool;
}

var deepEqualTests = []DeepEqualTest {
	// Equalities
	DeepEqualTest{ 1, 1, true },
	DeepEqualTest{ int32(1), int32(1), true },
	DeepEqualTest{ 0.5, 0.5, true },
	DeepEqualTest{ float32(0.5), float32(0.5), true },
	DeepEqualTest{ "hello", "hello", true },
	DeepEqualTest{ make([]int, 10), make([]int, 10), true },
	DeepEqualTest{ &[3]int{ 1, 2, 3 }, &[3]int{ 1, 2, 3 }, true },
	DeepEqualTest{ Basic{ 1, 0.5 }, Basic{ 1, 0.5 }, true },
	DeepEqualTest{ os.Error(nil), os.Error(nil), true },

	// Inequalities
	DeepEqualTest{ 1, 2, false },
	DeepEqualTest{ int32(1), int32(2), false },
	DeepEqualTest{ 0.5, 0.6, false },
	DeepEqualTest{ float32(0.5), float32(0.6), false },
	DeepEqualTest{ "hello", "hey", false },
	DeepEqualTest{ make([]int, 10), make([]int, 11), false },
	DeepEqualTest{ &[3]int{ 1, 2, 3 }, &[3]int{ 1, 2, 4 }, false },
	DeepEqualTest{ Basic{ 1, 0.5 }, Basic{ 1, 0.6 }, false },
	DeepEqualTest{ Basic{ 1, 0 }, Basic{ 2, 0 }, false },

	// Mismatched types
	DeepEqualTest{ 1, 1.0, false },
	DeepEqualTest{ int32(1), int64(1), false },
	DeepEqualTest{ 0.5, "hello", false },
	DeepEqualTest{ []int{ 1, 2, 3 }, [3]int{ 1, 2, 3 }, false },
	DeepEqualTest{ &[3]interface{} { 1, 2, 4 }, &[3]interface{} { 1, 2, "s" }, false },
	DeepEqualTest{ Basic{ 1, 0.5 }, NotBasic{ 1, 0.5 }, false },
}

func TestDeepEqual(t *testing.T) {
	for i, test := range deepEqualTests {
		if r := DeepEqual(test.a, test.b); r != test.eq {
			t.Errorf("DeepEqual(%v, %v) = %v, want %v", test.a, test.b, r, test.eq);
		}
	}
}

func TestTypeof(t *testing.T) {
	for i, test := range deepEqualTests {
		v := NewValue(test.a);
		if v == nil {
			continue;
		}
		typ := Typeof(test.a);
		if typ != v.Type() {
			t.Errorf("Typeof(%v) = %v, but NewValue(%v).Type() = %v", test.a, typ, test.a, v.Type());
		}
	}
}

func TestDeepEqualRecursiveStruct(t *testing.T) {
	a, b := new(Recursive), new(Recursive);
	*a = Recursive{ 12, a };
	*b = Recursive{ 12, b };
	if !DeepEqual(a, b) {
		t.Error("DeepEqual(recursive same) = false, want true");
	}
}

func TestDeepEqualComplexStruct(t *testing.T) {
	m := make(map[float]float);
	stra, strb := "hello", "hello";
	a, b := new(Complex), new(Complex);
	*a = Complex{5, [3]*Complex{a, b, a}, &stra, m};
	*b = Complex{5, [3]*Complex{b, a, a}, &strb, m};
	if !DeepEqual(a, b) {
		t.Error("DeepEqual(complex same) = false, want true");
	}
}

func TestDeepEqualComplexStructInequality(t *testing.T) {
	m := make(map[float]float);
	stra, strb := "hello", "helloo";  // Difference is here
	a, b := new(Complex), new(Complex);
	*a = Complex{5, [3]*Complex{a, b, a}, &stra, m};
	*b = Complex{5, [3]*Complex{b, a, a}, &strb, m};
	if DeepEqual(a, b) {
		t.Error("DeepEqual(complex different) = true, want false");
	}
}


func check2ndField(x interface{}, offs uintptr, t *testing.T) {
	s := NewValue(x).(*StructValue);
	f := s.Type().(*StructType).Field(1);
	if f.Offset != offs {
		t.Error("mismatched offsets in structure alignment:", f.Offset, offs);
	}
}

// Check that structure alignment & offsets viewed through reflect agree with those
// from the compiler itself.
func TestAlignment(t *testing.T) {
	type T1inner struct {
		a int
	}
	type T1 struct {
		T1inner;
		f int;
	}
	type T2inner struct {
		a, b int
	}
	type T2 struct {
		T2inner;
		f int;
	}

	x := T1{T1inner{2}, 17};
	check2ndField(x, uintptr(unsafe.Pointer(&x.f)) - uintptr(unsafe.Pointer(&x)), t);

	x1 := T2{T2inner{2, 3}, 17};
	check2ndField(x1, uintptr(unsafe.Pointer(&x1.f)) - uintptr(unsafe.Pointer(&x1)), t);
}

type IsNiller interface {
	IsNil() bool
}

func Nil(a interface{}, t *testing.T) {
	n := NewValue(a).(*StructValue).Field(0).(IsNiller);
	if !n.IsNil() {
		t.Errorf("%v should be nil", a)
	}
}

func NotNil(a interface{}, t *testing.T) {
	n := NewValue(a).(*StructValue).Field(0).(IsNiller);
	if n.IsNil() {
		t.Errorf("value of type %v should not be nil", NewValue(a).Type().String())
	}
}

func TestIsNil(t *testing.T) {
	// These do not implement IsNil
	doNotNil := []interface{}{ int(0), float32(0), struct{a int}{} };
	for i, ts := range doNotNil {
		ty := Typeof(ts);
		v := MakeZero(ty);
		if nilable, ok := v.(IsNiller); ok {
			t.Errorf("%s is nilable; should not be", ts)
		}
	}

	// These do implement IsNil.
	// Wrap in extra struct to hide interface type.
	doNil := []interface{}{
		struct{x *int}{},
		struct{x interface{}}{},
		struct{x map[string]int}{},
		struct{x func()bool}{},
		struct{x chan int}{},
		struct{x []string}{}
	};
	for i, ts := range doNil {
		ty := Typeof(ts).(*StructType).Field(0).Type;
		v := MakeZero(ty);
		if nilable, ok := v.(IsNiller); !ok {
			t.Errorf("%s %T is not nilable; should be", ts, v)
		}
	}

	// Check the implementations
	var pi struct {x *int}
	Nil(pi, t);
	pi.x = new(int);
	NotNil(pi, t);

	var si struct {x []int}
	Nil(si, t);
	si.x = make([]int, 10);
	NotNil(si, t);

	var ci struct {x chan int}
	Nil(ci, t);
	ci.x = make(chan int);
	NotNil(ci, t);

	var mi struct {x map[int]int}
	Nil(mi, t);
	mi.x = make(map[int]int);
	NotNil(mi, t);

	var ii struct {x interface {}}
	Nil(ii, t);
	ii.x = 2;
	NotNil(ii, t);

	var fi struct {x func(t *testing.T)}
	Nil(fi, t);
	fi.x = TestIsNil;
	NotNil(fi, t);
}

func TestInterfaceExtraction(t *testing.T) {
	var s struct {
		w io.Writer;
	}

	s.w = os.Stdout;
	v := Indirect(NewValue(&s)).(*StructValue).Field(0).Interface();
	if v != s.w.(interface{}) {
		t.Errorf("Interface() on interface: ", v, s.w);
	}
}

func TestInterfaceEditing(t *testing.T) {
	// strings are bigger than one word,
	// so the interface conversion allocates
	// memory to hold a string and puts that
	// pointer in the interface.
	var i interface{} = "hello";

	// if i pass the interface value by value
	// to NewValue, i should get a fresh copy
	// of the value.
	v := NewValue(i);

	// and setting that copy to "bye" should
	// not change the value stored in i.
	v.(*StringValue).Set("bye");
	if i.(string) != "hello" {
		t.Errorf(`Set("bye") changed i to %s`, i.(string));
	}

	// the same should be true of smaller items.
	i = 123;
	v = NewValue(i);
	v.(*IntValue).Set(234);
	if i.(int) != 123 {
		t.Errorf("Set(234) changed i to %d", i.(int));
	}
}

func TestNilPtrValueSub(t *testing.T) {
	var pi *int;
	if pv := NewValue(pi).(*PtrValue); pv.Elem() != nil {
		t.Error("NewValue((*int)(nil)).(*PtrValue).Elem() != nil");
	}
}

func TestMapAccess(t *testing.T) {
	m := map[string]int{ "a": 1, "b": 2 };
	mv := NewValue(m).(*MapValue);
	if n := mv.Len(); n != len(m) {
		t.Errorf("Len = %d, want %d", n, len(m));
	}
	keys := mv.Keys();
	i := 0;
	newmap := MakeMap(mv.Type().(*MapType));
	for k, v := range m {
		// Check that returned Keys match keys in range.
		// These aren't required to be in the same order,
		// but they are in this implementation, which makes
		// the test easier.
		if i >= len(keys) {
			t.Errorf("Missing key #%d %q", i, k);
		} else if kv := keys[i].(*StringValue); kv.Get() != k {
			t.Errorf("Keys[%d] = %q, want %q", i, kv.Get(), k);
		}
		i++;

		// Check that value lookup is correct.
		vv := mv.Get(NewValue(k));
		if vi := vv.(*IntValue).Get(); vi != v {
			t.Errorf("Key %q: have value %d, want %d", vi, v);
		}

		// Copy into new map.
		newmap.Put(NewValue(k), NewValue(v));
	}
	vv := mv.Get(NewValue("not-present"));
	if vv != nil {
		t.Errorf("Invalid key: got non-nil value %s", valueToString(vv));
	}

	newm := newmap.Interface().(map[string]int);
	if len(newm) != len(m) {
		t.Errorf("length after copy: newm=%d, m=%d", newm, m);
	}

	for k, v := range newm {
		mv, ok := m[k];
		if mv != v {
			t.Errorf("newm[%q] = %d, but m[%q] = %d, %v", k, v, k, mv, ok);
		}
	}
	
	newmap.Put(NewValue("a"), nil);
	v, ok := newm["a"];
	if ok {
		t.Errorf("newm[\"a\"] = %d after delete", v);
	}
}