forbid "eval" and "arguments" as function names

evanw · Feb 18, 2021 · 281733b · 281733b
1 parent 030715a
commit 281733b
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Showing 2 changed files with 18 additions and 6 deletions.
diff --git a/internal/js_parser/js_parser.go b/internal/js_parser/js_parser.go
@@ -4261,7 +4261,7 @@ func (p *parser) parseImportClause() ([]js_ast.ClauseItem, bool) {
 		}
 
 		// Reject forbidden names
-		if originalName == "eval" || originalName == "arguments" {
+		if isEvalOrArguments(originalName) {
 			r := js_lexer.RangeOfIdentifier(p.source, name.Loc)
 			p.log.AddRangeError(&p.source, r, fmt.Sprintf("Cannot use %q as an identifier here", originalName))
 		}
@@ -7359,10 +7359,8 @@ func (p *parser) visitBinding(binding js_ast.Binding, opts bindingOpts) {
 	case *js_ast.BIdentifier:
 		p.recordDeclaredSymbol(b.Ref)
 		name := p.symbols[b.Ref.InnerIndex].OriginalName
-		if p.isStrictMode() {
-			if name == "eval" || name == "arguments" {
-				p.markStrictModeFeature(evalOrArguments, js_lexer.RangeOfIdentifier(p.source, binding.Loc), name)
-			}
+		if isEvalOrArguments(name) {
+			p.markStrictModeFeature(evalOrArguments, js_lexer.RangeOfIdentifier(p.source, binding.Loc), name)
 		}
 		if opts.duplicateArgCheck != nil {
 			if opts.duplicateArgCheck[name] {
@@ -9572,11 +9570,16 @@ func canBeDeleted(expr js_ast.Expr) bool {
 	return false
 }
 
+// This function exists to tie all of these checks together in one place
+func isEvalOrArguments(name string) bool {
+	return name == "eval" || name == "arguments"
+}
+
 func (p *parser) isValidAssignmentTarget(expr js_ast.Expr) bool {
 	switch e := expr.Data.(type) {
 	case *js_ast.EIdentifier:
 		if p.isStrictMode() {
-			if name := p.loadNameFromRef(e.Ref); name == "eval" || name == "arguments" {
+			if name := p.loadNameFromRef(e.Ref); isEvalOrArguments(name) {
 				return false
 			}
 		}
@@ -11370,6 +11373,9 @@ func (p *parser) visitFn(fn *js_ast.Fn, scopeLoc logger.Loc) {
 
 	if fn.Name != nil {
 		p.recordDeclaredSymbol(fn.Name.Ref)
+		if name := p.symbols[fn.Name.Ref.InnerIndex].OriginalName; isEvalOrArguments(name) {
+			p.markStrictModeFeature(evalOrArguments, js_lexer.RangeOfIdentifier(p.source, fn.Name.Loc), name)
+		}
 	}
 
 	p.pushScopeForVisitPass(js_ast.ScopeFunctionArgs, scopeLoc)

diff --git a/internal/js_parser/js_parser_test.go b/internal/js_parser/js_parser_test.go
@@ -292,10 +292,16 @@ func TestStrictMode(t *testing.T) {
 	expectParseError(t, "'use strict'; arguments += 0", "<stdin>: error: Invalid assignment target\n")
 	expectParseError(t, "'use strict'; [arguments] = 0", "<stdin>: error: Invalid assignment target\n")
 
+	expectPrinted(t, "function eval() {}", "function eval() {\n}\n")
 	expectPrinted(t, "function f(eval) {}", "function f(eval) {\n}\n")
+	expectPrinted(t, "function arguments() {}", "function arguments() {\n}\n")
 	expectPrinted(t, "function f(arguments) {}", "function f(arguments) {\n}\n")
+	expectParseError(t, "'use strict'; function eval() {}",
+		"<stdin>: error: Declarations with the name \"eval\" cannot be used in strict mode\n")
 	expectParseError(t, "'use strict'; function f(eval) {}",
 		"<stdin>: error: Declarations with the name \"eval\" cannot be used in strict mode\n")
+	expectParseError(t, "'use strict'; function arguments() {}",
+		"<stdin>: error: Declarations with the name \"arguments\" cannot be used in strict mode\n")
 	expectParseError(t, "'use strict'; function f(arguments) {}",
 		"<stdin>: error: Declarations with the name \"arguments\" cannot be used in strict mode\n")