Reland "[parser] Forbid \08 in strict strings"

test/cctest/test-parsing.cc

 // Copyright 2012 the V8 project authors. All rights reserved.
 // Redistribution and use in source and binary forms, with or without
 // modification, are permitted provided that the following conditions are
 // met:
 //
 //     * Redistributions of source code must retain the above copyright
 //       notice, this list of conditions and the following disclaimer.
 //     * Redistributions in binary form must reproduce the above
 //       copyright notice, this list of conditions and the following
 //       disclaimer in the documentation and/or other materials provided
@@ skipping 5883 matching lines @@
     "\"foob\\{uc481}r\"",
     // This character is a valid unicode character, representable as a surrogate
     // pair, not representable as 4 hex digits.
     "\"foo\\u{10e6d}\"",
     // Max value for the unicode escape
     "\"\\u{10ffff}\"",
     NULL};
   RunParserSyncTest(context_data, data, kSuccess);
 }
 
+TEST(OctalEscapes) {
+  const char* sloppy_context_data[][2] = {{"", ""},    // as a directive
+                                          {"0;", ""},  // as a string literal
+                                          {NULL, NULL}};
+
+  const char* strict_context_data[][2] = {
+      {"'use strict';", ""},     // as a directive before 'use strict'
+      {"", ";'use strict';"},    // as a directive after 'use strict'
+      {"'use strict'; 0;", ""},  // as a string literal
+      {NULL, NULL}};
+
+  // clang-format off
+  const char* data[] = {
+    "'\\1'",
+    "'\\01'",
+    "'\\001'",
+    "'\\08'",
+    "'\\09'",
+    NULL};
+  // clang-format on
+
+  // Permitted in sloppy mode
+  RunParserSyncTest(sloppy_context_data, data, kSuccess);
+
+  // Error in strict mode
+  RunParserSyncTest(strict_context_data, data, kError);
+}
 
 TEST(ScanTemplateLiterals) {
   const char* context_data[][2] = {{"'use strict';", ""},
                                    {"function foo(){ 'use strict';"
                                     "  var a, b, c; return ", "}"},
                                    {NULL, NULL}};
 
   const char* data[] = {
       "``",
       "`no-subst-template`",
@@ skipping 1191 matching lines @@
 
 TEST(TemplateEscapesPositiveTests) {
   // clang-format off
   const char* context_data[][2] = {
     {"", ""},
     {"'use strict';", ""},
     {NULL, NULL}};
 
   // clang-format off
   const char* data[] = {
+    "tag`\\08`",
     "tag`\\01`",
     "tag`\\01${0}right`",
     "tag`left${0}\\01`",
     "tag`left${0}\\01${1}right`",
     "tag`\\1`",
     "tag`\\1${0}right`",
     "tag`left${0}\\1`",
     "tag`left${0}\\1${1}right`",
     "tag`\\xg`",
     "tag`\\xg${0}right`",
@@ skipping 63 matching lines @@
 
 TEST(TemplateEscapesNegativeTests) {
   // clang-format off
   const char* context_data[][2] = {
     {"", ""},
     {"'use strict';", ""},
     {NULL, NULL}};
 
   // clang-format off
   const char* data[] = {
+    "`\\08`",
     "`\\01`",
     "`\\01${0}right`",
     "`left${0}\\01`",
     "`left${0}\\01${1}right`",
     "`\\1`",
     "`\\1${0}right`",
     "`left${0}\\1`",
     "`left${0}\\1${1}right`",
     "`\\xg`",
     "`\\xg${0}right`",
@@ skipping 3131 matching lines @@
       CHECK(loop_var->IsStackLocal());
       CHECK_EQ(loop_block->ContextLocalCount(), 0);
 
       i::Variable* loop_var2 = loop_block->inner_scope()->LookupLocal(var_name);
       CHECK_NE(loop_var, loop_var2);
       CHECK(loop_var2->IsContextSlot());
       CHECK_EQ(loop_block->inner_scope()->ContextLocalCount(), 1);
     });
   }
 }