1 files changed, 97 insertions, 0 deletions
diff --git a/test/interface/fake.go b/test/interface/fake.go
new file mode 100644
index 0000000..861a640
--- /dev/null
+++ b/test/interface/fake.go
@@ -0,0 +1,97 @@
+// run
+
+// 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.
+
+// Test interface comparisons using types hidden
+// inside reflected-on structs.
+
+package main
+
+import "reflect"
+
+type T struct {
+	F float32
+	G float32
+
+	S string
+	T string
+
+	U uint32
+	V uint32
+
+	W uint32
+	X uint32
+
+	Y uint32
+	Z uint32
+}
+
+func add(s, t string) string {
+	return s + t
+}
+
+func assert(b bool) {
+	if !b {
+		panic("assert")
+	}
+}
+
+func main() {
+	var x T
+	x.F = 1.0
+	x.G = x.F
+	x.S = add("abc", "def")
+	x.T = add("abc", "def")
+	x.U = 1
+	x.V = 2
+	x.W = 1 << 28
+	x.X = 2 << 28
+	x.Y = 0x12345678
+	x.Z = x.Y
+
+	// check mem and string
+	v := reflect.ValueOf(x)
+	i := v.Field(0)
+	j := v.Field(1)
+	assert(i.Interface() == j.Interface())
+
+	s := v.Field(2)
+	t := v.Field(3)
+	assert(s.Interface() == t.Interface())
+
+	// make sure different values are different.
+	// make sure whole word is being compared,
+	// not just a single byte.
+	i = v.Field(4)
+	j = v.Field(5)
+	assert(i.Interface() != j.Interface())
+
+	i = v.Field(6)
+	j = v.Field(7)
+	assert(i.Interface() != j.Interface())
+
+	i = v.Field(8)
+	j = v.Field(9)
+	assert(i.Interface() == j.Interface())
+}
+
+/*
+comparing uncomparable type float32
+throw: interface compare
+
+panic PC=0x28ceb8 [1]
+throw+0x41 /Users/rsc/goX/src/runtime/runtime.c:54
+	throw(0x3014a, 0x0)
+ifaceeq+0x15c /Users/rsc/goX/src/runtime/iface.c:501
+	ifaceeq(0x2aa7c0, 0x0, 0x0, 0x0, 0x2aa7c0, ...)
+sys·ifaceeq+0x48 /Users/rsc/goX/src/runtime/iface.c:527
+	sys·ifaceeq(0x2aa7c0, 0x0, 0x0, 0x0, 0x2aa7c0, ...)
+main·main+0x190 /Users/rsc/goX/src/cmd/gc/x.go:10
+	main·main()
+mainstart+0xf /Users/rsc/goX/src/runtime/amd64/asm.s:53
+	mainstart()
+sys·Goexit /Users/rsc/goX/src/runtime/proc.c:124
+	sys·Goexit()
+*/