go/printer: parenthesize literal function types in conversions
Also: gofmt -w src misc
R=r
CC=golang-dev, iant
https://golang.org/cl/6591071
diff --git a/src/pkg/go/printer/nodes.go b/src/pkg/go/printer/nodes.go
index 01a7473..6eee9a9 100644
--- a/src/pkg/go/printer/nodes.go
+++ b/src/pkg/go/printer/nodes.go
@@ -791,7 +791,14 @@
if len(x.Args) > 1 {
depth++
}
- p.expr1(x.Fun, token.HighestPrec, depth)
+ if _, ok := x.Fun.(*ast.FuncType); ok {
+ // conversions to literal function types require parentheses around the type
+ p.print(token.LPAREN)
+ p.expr1(x.Fun, token.HighestPrec, depth)
+ p.print(token.RPAREN)
+ } else {
+ p.expr1(x.Fun, token.HighestPrec, depth)
+ }
p.print(x.Lparen, token.LPAREN)
if x.Ellipsis.IsValid() {
p.exprList(x.Lparen, x.Args, depth, 0, x.Ellipsis)
diff --git a/src/pkg/go/printer/testdata/expressions.golden b/src/pkg/go/printer/testdata/expressions.golden
index 45fa4d9..4291c55 100644
--- a/src/pkg/go/printer/testdata/expressions.golden
+++ b/src/pkg/go/printer/testdata/expressions.golden
@@ -647,3 +647,18 @@
a...,
)
}
+
+// Literal function types in conversions must be parenthesized;
+// for now go/parser accepts the unparenthesized form where it
+// is non-ambiguous.
+func _() {
+ // these conversions should be rewritten to look
+ // the same as the parenthesized conversions below
+ _ = (func())(nil)
+ _ = (func(x int) float)(nil)
+ _ = (func() func() func())(nil)
+
+ _ = (func())(nil)
+ _ = (func(x int) float)(nil)
+ _ = (func() func() func())(nil)
+}
diff --git a/src/pkg/go/printer/testdata/expressions.input b/src/pkg/go/printer/testdata/expressions.input
index f545c66..1ec12a0 100644
--- a/src/pkg/go/printer/testdata/expressions.input
+++ b/src/pkg/go/printer/testdata/expressions.input
@@ -676,3 +676,18 @@
a...,
)
}
+
+// Literal function types in conversions must be parenthesized;
+// for now go/parser accepts the unparenthesized form where it
+// is non-ambiguous.
+func _() {
+ // these conversions should be rewritten to look
+ // the same as the parenthesized conversions below
+ _ = func()()(nil)
+ _ = func(x int)(float)(nil)
+ _ = func() func() func()()(nil)
+
+ _ = (func()())(nil)
+ _ = (func(x int)(float))(nil)
+ _ = (func() func() func()())(nil)
+}
diff --git a/src/pkg/go/printer/testdata/expressions.raw b/src/pkg/go/printer/testdata/expressions.raw
index 87a4b00..062900e 100644
--- a/src/pkg/go/printer/testdata/expressions.raw
+++ b/src/pkg/go/printer/testdata/expressions.raw
@@ -647,3 +647,18 @@
a...,
)
}
+
+// Literal function types in conversions must be parenthesized;
+// for now go/parser accepts the unparenthesized form where it
+// is non-ambiguous.
+func _() {
+ // these conversions should be rewritten to look
+ // the same as the parenthesized conversions below
+ _ = (func())(nil)
+ _ = (func(x int) float)(nil)
+ _ = (func() func() func())(nil)
+
+ _ = (func())(nil)
+ _ = (func(x int) float)(nil)
+ _ = (func() func() func())(nil)
+}
diff --git a/src/pkg/reflect/all_test.go b/src/pkg/reflect/all_test.go
index 5dad071..5ddd6be 100644
--- a/src/pkg/reflect/all_test.go
+++ b/src/pkg/reflect/all_test.go
@@ -1494,7 +1494,7 @@
}
// Curried method of value.
- tfunc := TypeOf(func(int) int(nil))
+ tfunc := TypeOf((func(int) int)(nil))
v := ValueOf(p).Method(1)
if tt := v.Type(); tt != tfunc {
t.Errorf("Value Method Type is %s; want %s", tt, tfunc)
