gc: implement []int(string) and []byte(string)

R=ken2
CC=golang-dev
http://codereview.appspot.com/224060

2 files changed, 57 insertions, 0 deletions

diff --git a/test/convlit.go b/test/convlit.go
index e65dad3df..22415bb32 100644
--- a/test/convlit.go
+++ b/test/convlit.go
@@ -35,3 +35,30 @@ var good2 int = 1.0;
 var good3 int = 1e9;
 var good4 float = 1e20;
 
+// explicit conversion of string is okay
+var _ = []int("abc")
+var _ = []byte("abc")
+
+// implicit is not
+var _ []int = "abc"	// ERROR "cannot use|incompatible|invalid"
+var _ []byte = "abc"	// ERROR "cannot use|incompatible|invalid"
+
+// named string is okay
+type Tstring string
+var ss Tstring = "abc"
+var _ = []int(ss)
+var _ = []byte(ss)
+
+// implicit is still not
+var _ []int = ss	// ERROR "cannot use|incompatible|invalid"
+var _ []byte = ss	// ERROR "cannot use|incompatible|invalid"
+
+// named slice is not
+type Tint []int
+type Tbyte []byte
+var _ = Tint("abc")	// ERROR "convert|incompatible|invalid"
+var _ = Tbyte("abc")	// ERROR "convert|incompatible|invalid"
+
+// implicit is still not
+var _ Tint = "abc"	// ERROR "cannot use|incompatible|invalid"
+var _ Tbyte = "abc"	// ERROR "cannot use|incompatible|invalid"
diff --git a/test/string_lit.go b/test/string_lit.go
index 547be8003..88b5d251f 100644
--- a/test/string_lit.go
+++ b/test/string_lit.go
@@ -34,6 +34,19 @@ func assert(a, b, c string) {
 	}
 }
 
+const (
+	gx1 = "aä本☺"
+	gx2 = "aä\xFF\xFF本☺"
+	gx2fix = "aä\uFFFD\uFFFD本☺"
+)
+
+var (
+	gr1 = []int(gx1)
+	gr2 = []int(gx2)
+	gb1 = []byte(gx1)
+	gb2 = []byte(gx2)
+)
+
 func main() {
 	ecode = 0;
 	s :=
@@ -86,5 +99,22 @@ func main() {
 	r = 0x10ffff + 1;
 	s = string(r);
 	assert(s, "\xef\xbf\xbd", "too-large rune");
+
+	assert(string(gr1), gx1, "global ->[]int")
+	assert(string(gr2), gx2fix, "global invalid ->[]int")
+	assert(string(gb1), gx1, "->[]byte")
+	assert(string(gb2), gx2, "global invalid ->[]byte")
+
+	var (
+		r1 = []int(gx1)
+		r2 = []int(gx2)
+		b1 = []byte(gx1)
+		b2 = []byte(gx2)
+	)
+	assert(string(r1), gx1, "->[]int")
+	assert(string(r2), gx2fix, "invalid ->[]int")
+	assert(string(b1), gx1, "->[]byte")
+	assert(string(b2), gx2, "invalid ->[]byte")
+
 	os.Exit(ecode);
 }