From: Robert Griesemer <gri@golang.org>
Date: Fri, 26 Aug 2022 04:10:36 +0000 (-0700)
Subject: go/parser: check that go/defer expressions are not parenthesized
X-Git-Tag: go1.20rc1~1286
X-Git-Url: http://www.git.cypherpunks.su/?a=commitdiff_plain;h=a74d46d8ff44abe409282bf1a9a9ab1b0b2cdaa0;p=gostls13.git

go/parser: check that go/defer expressions are not parenthesized

Logic matches the code in the syntax package.
This error was missing from go/parser and go/types.
Added some tests.

For #54511.

Change-Id: I418de4bd4c7169457b424366caae70227a92a761
Reviewed-on: https://go-review.googlesource.com/c/go/+/425795
Auto-Submit: Robert Griesemer <gri@google.com>
TryBot-Result: Gopher Robot <gobot@golang.org>
Run-TryBot: Robert Griesemer <gri@google.com>
Reviewed-by: Alan Donovan <adonovan@google.com>
Reviewed-by: Robert Griesemer <gri@google.com>
---

diff --git a/src/go/parser/parser.go b/src/go/parser/parser.go
index 3d4d83c4a4..26ba7b2892 100644
--- a/src/go/parser/parser.go
+++ b/src/go/parser/parser.go
@@ -1928,6 +1928,10 @@ func (p *parser) checkAssignStmt(as *ast.AssignStmt) {
 
 func (p *parser) parseCallExpr(callType string) *ast.CallExpr {
 	x := p.parseRhs() // could be a conversion: (some type)(x)
+	if t := unparen(x); t != x {
+		p.error(x.Pos(), fmt.Sprintf("expression in %s must not be parenthesized", callType))
+		x = t
+	}
 	if call, isCall := x.(*ast.CallExpr); isCall {
 		return call
 	}
diff --git a/src/go/parser/short_test.go b/src/go/parser/short_test.go
index 2d9016aadd..ea8b087bae 100644
--- a/src/go/parser/short_test.go
+++ b/src/go/parser/short_test.go
@@ -159,7 +159,9 @@ var invalids = []string{
 	`package p; func f() { for i /* ERROR "boolean or range expression" */ , x = []string {} }`,
 	`package p; func f() { for i /* ERROR "boolean or range expression" */ , x := []string {} }`,
 	`package p; func f() { go f /* ERROR HERE "must be function call" */ }`,
+	`package p; func f() { go ( /* ERROR "must not be parenthesized" */ f()) }`,
 	`package p; func f() { defer func() {} /* ERROR HERE "must be function call" */ }`,
+	`package p; func f() { defer ( /* ERROR "must not be parenthesized" */ f()) }`,
 	`package p; func f() { go func() { func() { f(x func /* ERROR "missing ','" */ (){}) } } }`,
 	`package p; func _() (type /* ERROR "found 'type'" */ T)(T)`,
 	`package p; func (type /* ERROR "found 'type'" */ T)(T) _()`,
diff --git a/src/go/types/testdata/check/stmt0.go b/src/go/types/testdata/check/stmt0.go
index 0caebcf544..14a37c1ed9 100644
--- a/src/go/types/testdata/check/stmt0.go
+++ b/src/go/types/testdata/check/stmt0.go
@@ -231,6 +231,7 @@ func selects() {
 func gos() {
 	go 1; /* ERROR "must be function call" */
 	go int /* ERROR "go requires function call, not conversion" */ (0)
+	go ( /* ERROR expression in go must not be parenthesized */ gos())
 	go gos()
 	var c chan int
 	go close(c)
@@ -240,6 +241,7 @@ func gos() {
 func defers() {
 	defer 1; /* ERROR "must be function call" */
 	defer int /* ERROR "defer requires function call, not conversion" */ (0)
+	defer ( /* ERROR expression in defer must not be parenthesized */ defers())
 	defer defers()
 	var c chan int
 	defer close(c)