[njs] Checking for duplicate function parameter names.

[Dmitry Volyntsev]

details:   https://hg.nginx.org/njs/rev/4df50ca085e7
branches:  
changeset: 879:4df50ca085e7
user:      hongzhidao <hongzhidao at gmail.com>
date:      Thu Apr 11 21:13:03 2019 +0800
description:
Checking for duplicate function parameter names.

This closes #80 issue on Github.

diffstat:

 njs/njs_parser.c         |   6 ++++++
 njs/test/njs_unit_test.c |  21 +++++++++++++++++++++
 2 files changed, 27 insertions(+), 0 deletions(-)

diffs (47 lines):

diff -r b9d619068453 -r 4df50ca085e7 njs/njs_parser.c
--- a/njs/njs_parser.c	Thu Apr 11 16:32:06 2019 +0300
+++ b/njs/njs_parser.c	Thu Apr 11 21:13:03 2019 +0800
@@ -837,6 +837,12 @@ njs_parser_lambda_argument(njs_vm_t *vm,
         return NJS_TOKEN_ERROR;
     }
 
+    if (arg->index > 0) {
+        njs_parser_syntax_error(vm, parser, "Duplicate parameter names");
+
+        return NJS_TOKEN_ILLEGAL;
+    }
+
     arg->index = index;
 
     ret = njs_name_copy(vm, &arg->name, njs_parser_text(parser));
diff -r b9d619068453 -r 4df50ca085e7 njs/test/njs_unit_test.c
--- a/njs/test/njs_unit_test.c	Thu Apr 11 16:32:06 2019 +0300
+++ b/njs/test/njs_unit_test.c	Thu Apr 11 21:13:03 2019 +0800
@@ -5716,6 +5716,27 @@ static njs_unit_test_t  njs_test[] =
                  "binded.length"),
       nxt_string("0") },
 
+    { nxt_string("function f(a,a) { };"),
+      nxt_string("SyntaxError: Duplicate parameter names in 1") },
+
+    { nxt_string("function f(a,b,a) { };"),
+      nxt_string("SyntaxError: Duplicate parameter names in 1") },
+
+    { nxt_string("function f(a, ...a) { };"),
+      nxt_string("SyntaxError: Duplicate parameter names in 1") },
+
+    { nxt_string("(function(a,a) { })"),
+      nxt_string("SyntaxError: Duplicate parameter names in 1") },
+
+    { nxt_string("(function(a,...a) { })"),
+      nxt_string("SyntaxError: Duplicate parameter names in 1") },
+
+    { nxt_string("(function f(a,a) { })"),
+      nxt_string("SyntaxError: Duplicate parameter names in 1") },
+
+    { nxt_string("(function f(a,...a) { })"),
+      nxt_string("SyntaxError: Duplicate parameter names in 1") },
+
     { nxt_string("function f(a,b) { }; f.length"),
       nxt_string("2") },