reflect: fix method indexing for non-ASCII exported methods

Currently, methods are sorted by name. This happens to guarantee that exported ASCII methods appear before non-exported ASCII methods, but this breaks down when Unicode method names are considered. Type.Method already accounts for this by always indexing into the slice returned by exportedMethods. This CL makes Value.Method do the same. Fixes #22073. Change-Id: I9bfc6bbfb7353e0bd3c439a15d1c3da60d16d209 Reviewed-on: https://go-review.googlesource.com/66770 Run-TryBot: Matthew Dempsky <[email protected]> TryBot-Result: Gobot Gobot <[email protected]> Reviewed-by: David Crawshaw <[email protected]>
golang · Sep 28, 2017 · 6f1724f · 6f1724f
1 parent b3cae37
commit 6f1724f
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Showing 2 changed files with 22 additions and 6 deletions.
diff --git a/src/reflect/all_test.go b/src/reflect/all_test.go
@@ -6405,3 +6405,19 @@ func TestIssue22031(t *testing.T) {
 		}
 	}
 }
+
+type NonExportedFirst int
+
+func (i NonExportedFirst) ΦExported()       {}
+func (i NonExportedFirst) nonexported() int { panic("wrong") }
+
+func TestIssue22073(t *testing.T) {
+	m := ValueOf(NonExportedFirst(0)).Method(0)
+
+	if got := m.Type().NumOut(); got != 0 {
+		t.Errorf("NumOut: got %v, want 0", got)
+	}
+
+	// Shouldn't panic.
+	m.Call(nil)
+}
diff --git a/src/reflect/value.go b/src/reflect/value.go
@@ -584,11 +584,11 @@ func methodReceiver(op string, v Value, methodIndex int) (rcvrtype, t *rtype, fn
 		t = tt.typeOff(m.typ)
 	} else {
 		rcvrtype = v.typ
-		ut := v.typ.uncommon()
-		if ut == nil || uint(i) >= uint(ut.mcount) {
+		ms := v.typ.exportedMethods()
+		if uint(i) >= uint(len(ms)) {
 			panic("reflect: internal error: invalid method index")
 		}
-		m := ut.methods()[i]
+		m := ms[i]
 		if !v.typ.nameOff(m.name).isExported() {
 			panic("reflect: " + op + " of unexported method")
 		}
@@ -1717,11 +1717,11 @@ func (v Value) Type() Type {
 		return v.typ.typeOff(m.typ)
 	}
 	// Method on concrete type.
-	ut := v.typ.uncommon()
-	if ut == nil || uint(i) >= uint(ut.mcount) {
+	ms := v.typ.exportedMethods()
+	if uint(i) >= uint(len(ms)) {
 		panic("reflect: internal error: invalid method index")
 	}
-	m := ut.methods()[i]
+	m := ms[i]
 	return v.typ.typeOff(m.mtyp)
 }