duplicate arg checks "use strict" in body

evanw · Feb 18, 2021 · c4a6943 · c4a6943
1 parent ef31c4f
commit c4a6943
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Showing 2 changed files with 7 additions and 1 deletion.
diff --git a/internal/js_parser/js_parser.go b/internal/js_parser/js_parser.go
@@ -8977,7 +8977,7 @@ func (p *parser) visitArgs(args []js_ast.Arg, opts visitArgsOpts) {
 	// the same BindingIdentifier in a FormalParameterList is only allowed for
 	// functions which have simple parameter lists and which are not defined in
 	// strict mode code."
-	if opts.isUniqueFormalParameters || !hasSimpleArgs || p.isStrictMode() {
+	if opts.isUniqueFormalParameters || hasUseStrict || !hasSimpleArgs || p.isStrictMode() {
 		duplicateArgCheck = make(map[string]bool)
 	}
 

diff --git a/internal/js_parser/js_parser_test.go b/internal/js_parser/js_parser_test.go
@@ -257,6 +257,12 @@ func TestStrictMode(t *testing.T) {
 	expectPrinted(t, "({ f: function*(a, a) {} })", "({f: function* (a, a) {\n}});\n")
 	expectPrinted(t, "({ f: async function(a, a) {} })", "({f: async function(a, a) {\n}});\n")
 
+	expectParseError(t, "function f(a, a) { 'use strict' }", "<stdin>: error: \"a\" cannot be bound multiple times in the same parameter list\n")
+	expectParseError(t, "function *f(a, a) { 'use strict' }", "<stdin>: error: \"a\" cannot be bound multiple times in the same parameter list\n")
+	expectParseError(t, "async function f(a, a) { 'use strict' }", "<stdin>: error: \"a\" cannot be bound multiple times in the same parameter list\n")
+	expectParseError(t, "(function(a, a) { 'use strict' })", "<stdin>: error: \"a\" cannot be bound multiple times in the same parameter list\n")
+	expectParseError(t, "(function*(a, a) { 'use strict' })", "<stdin>: error: \"a\" cannot be bound multiple times in the same parameter list\n")
+	expectParseError(t, "(async function(a, a) { 'use strict' })", "<stdin>: error: \"a\" cannot be bound multiple times in the same parameter list\n")
 	expectParseError(t, "function f(a, [a]) {}", "<stdin>: error: \"a\" cannot be bound multiple times in the same parameter list\n")
 	expectParseError(t, "function f([a], a) {}", "<stdin>: error: \"a\" cannot be bound multiple times in the same parameter list\n")
 	expectParseError(t, "'use strict'; function f(a, a) {}", "<stdin>: error: \"a\" cannot be bound multiple times in the same parameter list\n")