exp/template: forgot to allow . as a function argument

R=golang-dev, adg
CC=golang-dev
https://golang.org/cl/4671053

src/pkg/exp/template/exec.go

@@ -284,7 +284,10 @@ isFirst, canBeMethod bool) reflect.Value {
 		if canBeMethod {
 			// Need to get to a value of type *T to guarantee we see all
 			// methods of T and *T.
-			ptr := data.Addr()
+			ptr := data
+			if ptr.CanAddr() {
+				ptr = ptr.Addr()
+			}
 			if method, ok := methodByName(ptr.Type(), fieldName); ok {
 				return s.evalCall(ptr, method.Func, fieldName, true, args, final)
 			}
@@ -382,8 +385,14 @@ func (s *state) evalCall(v, fun reflect.Value, name string, isMethod bool, args
 }
 
 func (s *state) evalArg(data reflect.Value, typ reflect.Type, n node) reflect.Value {
-	if field, ok := n.(*fieldNode); ok {
-		value := s.evalFieldNode(data, field, []node{n}, zero)
+	switch arg := n.(type) {
+	case *dotNode:
+		if !data.Type().AssignableTo(typ) {
+			s.errorf("wrong type for value; expected %s; got %s", typ, data.Type())
+		}
+		return data
+	case *fieldNode:
+		value := s.evalFieldNode(data, arg, []node{n}, zero)
 		if !value.Type().AssignableTo(typ) {
 			s.errorf("wrong type for value; expected %s; got %s", typ, value.Type())
 		}

src/pkg/exp/template/exec_test.go

@@ -161,7 +161,7 @@ var execTests = []execTest{
 	{"*[]int[1]", "{{index .PSI 1}}", "22", tVal, true},
 	{"NIL", "{{.NIL}}", "<nil>", tVal, true},
 
-	// Emtpy interfaces holding values.
+	// Empty interfaces holding values.
 	{"empty nil", "{{.Empty0}}", "<no value>", tVal, true},
 	{"empty with int", "{{.Empty1}}", "3", tVal, true},
 	{"empty with string", "{{.Empty2}}", "empty2", tVal, true},
@@ -200,7 +200,7 @@ var execTests = []execTest{
 	{"printf float", `{{printf "%g" 3.5}}`, "3.5", tVal, true},
 	{"printf complex", `{{printf "%g" 1+7i}}`, "(1+7i)", tVal, true},
 	{"printf string", `{{printf "%s" "hello"}}`, "hello", tVal, true},
-	{"printf function", `{{printf "%#q" gopher}}`, "`gopher`", tVal, true},
+	{"printf function", `{{printf "%#q" zeroArgs}}`, "`zeroArgs`", tVal, true},
 	{"printf field", `{{printf "%s" .U.V}}`, "v", tVal, true},
 	{"printf method", `{{printf "%s" .Method0}}`, "M0", tVal, true},
 	{"printf lots", `{{printf "%d %s %g %s" 127 "hello" 7-3i .Method0}}`, "127 hello (7-3i) M0", tVal, true},
@@ -273,13 +273,17 @@ var execTests = []execTest{
 	{"error method, no error", "{{.EPERM false}}", "false", tVal, true},
 }
 
-func gopher() string {
-	return "gopher"
+func zeroArgs() string {
+	return "zeroArgs"
+}
+
+func oneArg(a string) string {
+	return "oneArg=" + a
 }
 
 func testExecute(execTests []execTest, set *Set, t *testing.T) {
 	b := new(bytes.Buffer)
-	funcs := FuncMap{"gopher": gopher}
+	funcs := FuncMap{"zeroArgs": zeroArgs, "oneArg": oneArg}
 	for _, test := range execTests {
 		tmpl := New(test.name).Funcs(funcs)
 		err := tmpl.Parse(test.input)

src/pkg/exp/template/set_test.go

@@ -81,6 +81,10 @@ var setExecTests = []execTest{
 	{"invoke dot []int", `{{template "dot" .SI}}`, "[3 4 5]", tVal, true},
 	{"invoke dotV", `{{template "dotV" .U}}`, "v", tVal, true},
 	{"invoke nested int", `{{template "nested" .I}}`, "17", tVal, true},
+
+	// User-defined function: test argument evaluator.
+	{"testFunc literal", `{{oneArg "joe"}}`, "oneArg=joe", tVal, true},
+	{"testFunc .", `{{oneArg .}}`, "oneArg=joe", "joe", true},
 }
 
 const setText = `