Improve expected identifier checks. (#3064)

Checks for "of" or "from" does not accept quoted strings.

JerryScript-DCO-1.0-Signed-off-by: Zoltan Herczeg zherczeg.u-szeged@partner.samsung.com

jerry-core/parser/js/common.h

@@ -47,6 +47,7 @@
  */
 typedef enum
 {
+  /* The LEXER_IS_IDENT_OR_STRING macro must be updated if the order is changed. */
   LEXER_IDENT_LITERAL = 0,          /**< identifier literal */
   LEXER_STRING_LITERAL = 1,         /**< string literal */
   LEXER_NUMBER_LITERAL = 2,         /**< number literal */
@@ -56,6 +57,11 @@ typedef enum
                                          used by the byte code generator. */
 } lexer_literal_type_t;
 
+/**
+ * Checks whether the literal type is identifier or string.
+ */
+#define LEXER_IS_IDENT_OR_STRING(literal_type) ((literal_type) <= LEXER_STRING_LITERAL)
+
 /**
  * Flag bits for status_flags member of lexer_literal_t.
  */

jerry-core/parser/js/js-lexer.c

@@ -2331,12 +2331,12 @@ lexer_expect_object_literal_id (parser_context_t *context_p, /**< context */
         if (context_p->source_p < context_p->source_end_p
             && context_p->source_p[0] != LIT_CHAR_COLON)
         {
-          if (lexer_compare_raw_identifier_to_current (context_p, "get", 3))
+          if (lexer_compare_literal_to_string (context_p, "get", 3))
           {
             context_p->token.type = LEXER_PROPERTY_GETTER;
             return;
           }
-          else if (lexer_compare_raw_identifier_to_current (context_p, "set", 3))
+          else if (lexer_compare_literal_to_string (context_p, "set", 3))
           {
             context_p->token.type = LEXER_PROPERTY_SETTER;
             return;
@@ -2345,8 +2345,7 @@ lexer_expect_object_literal_id (parser_context_t *context_p, /**< context */
       }
 
 #if ENABLED (JERRY_ES2015_CLASS)
-      if (is_class_method
+      if (is_class_method && lexer_compare_literal_to_string (context_p, "static", 6))
-          && lexer_compare_raw_identifier_to_current (context_p, "static", 6))
       {
         context_p->token.type = LEXER_KEYW_STATIC;
         return;
@@ -2406,8 +2405,7 @@ lexer_expect_object_literal_id (parser_context_t *context_p, /**< context */
     if (create_literal_object)
     {
 #if ENABLED (JERRY_ES2015_CLASS)
-      if (is_class_method
+      if (is_class_method && lexer_compare_literal_to_string (context_p, "constructor", 11))
-          && lexer_compare_raw_identifier_to_current (context_p, "constructor", 11))
       {
         context_p->token.type = LEXER_CLASS_CONSTRUCTOR;
         return;
@@ -2447,11 +2445,11 @@ lexer_scan_identifier (parser_context_t *context_p, /**< context */
       if (context_p->source_p < context_p->source_end_p
           && context_p->source_p[0] != LIT_CHAR_COLON)
       {
-        if (lexer_compare_raw_identifier_to_current (context_p, "get", 3))
+        if (lexer_compare_literal_to_string (context_p, "get", 3))
         {
           context_p->token.type = LEXER_PROPERTY_GETTER;
         }
-        else if (lexer_compare_raw_identifier_to_current (context_p, "set", 3))
+        else if (lexer_compare_literal_to_string (context_p, "set", 3))
         {
           context_p->token.type = LEXER_PROPERTY_SETTER;
         }
@@ -2573,27 +2571,46 @@ lexer_compare_identifier_to_current (parser_context_t *context_p, /**< context *
 } /* lexer_compare_identifier_to_current */
 
 /**
- * Compares the current identifier in the context to the parameter identifier
+ * Compares the current identifier to an expected identifier.
  *
  * Note:
  *   Escape sequences are not allowed.
  *
- * @return true if the input identifiers are the same
+ * @return true if they are the same, false otherwise
  */
-bool
+inline bool JERRY_ATTR_ALWAYS_INLINE
-lexer_compare_raw_identifier_to_current (parser_context_t *context_p, /**< context */
+lexer_compare_literal_to_identifier (parser_context_t *context_p, /**< context */
-                                         const char *right_ident_p, /**< identifier */
+                                     const char *identifier_p, /**< identifier */
-                                         size_t right_ident_length) /**< identifier length */
+                                     size_t identifier_length) /**< identifier length */
 {
-  lexer_lit_location_t *left_ident_p = &context_p->token.lit_location;
+  /* Checking has_escape is unnecessary because memcmp will fail if escape sequences are present. */
+  return (context_p->token.type == LEXER_LITERAL
+          && context_p->token.lit_location.type == LEXER_IDENT_LITERAL
+          && context_p->token.lit_location.length == identifier_length
+          && memcmp (context_p->token.lit_location.char_p, identifier_p, identifier_length) == 0);
+} /* lexer_compare_literal_to_identifier */
 
-  if (left_ident_p->length != right_ident_length || left_ident_p->has_escape)
+/**
-  {
+ * Compares the current identifier or string to an expected string.
-    return 0;
+ *
-  }
+ * Note:
+ *   Escape sequences are not allowed.
+ *
+ * @return true if they are the same, false otherwise
+ */
+inline bool JERRY_ATTR_ALWAYS_INLINE
+lexer_compare_literal_to_string (parser_context_t *context_p, /**< context */
+                                 const char *string_p, /**< string */
+                                 size_t string_length) /**< string length */
+{
+  JERRY_ASSERT (context_p->token.type == LEXER_LITERAL
+                && (context_p->token.lit_location.type == LEXER_IDENT_LITERAL
+                    || context_p->token.lit_location.type == LEXER_STRING_LITERAL));
 
-  return memcmp (left_ident_p->char_p, right_ident_p, right_ident_length) == 0;
+  /* Checking has_escape is unnecessary because memcmp will fail if escape sequences are present. */
-} /* lexer_compare_raw_identifier_to_current */
+  return (context_p->token.lit_location.length == string_length
+          && memcmp (context_p->token.lit_location.char_p, string_p, string_length) == 0);
+} /* lexer_compare_literal_to_string */
 
 /**
  * Convert binary lvalue token to binary token

jerry-core/parser/js/js-parser-expr.c

@@ -442,7 +442,8 @@ parser_parse_class_literal (parser_context_t *context_p) /**< context */
         is_computed = true;
       }
       else if (!(status_flags & PARSER_CLASS_STATIC_FUNCTION)
-               && lexer_compare_raw_identifier_to_current (context_p, "constructor", 11))
+               && LEXER_IS_IDENT_OR_STRING (context_p->token.lit_location.type)
+               && lexer_compare_literal_to_string (context_p, "constructor", 11))
       {
         parser_raise_error (context_p, PARSER_ERR_CLASS_CONSTRUCTOR_AS_ACCESSOR);
       }
@@ -538,7 +539,8 @@ parser_parse_class_literal (parser_context_t *context_p) /**< context */
       is_computed = true;
     }
     else if ((status_flags & PARSER_CLASS_STATIC_FUNCTION)
-             && lexer_compare_raw_identifier_to_current (context_p, "prototype", 9))
+             && LEXER_IS_IDENT_OR_STRING (context_p->token.lit_location.type)
+             && lexer_compare_literal_to_string (context_p, "prototype", 9))
     {
       parser_raise_error (context_p, PARSER_ERR_CLASS_STATIC_PROTOTYPE);
     }

jerry-core/parser/js/js-parser-internal.h

@@ -521,8 +521,9 @@ void lexer_convert_push_number_to_push_literal (parser_context_t *context_p);
 uint16_t lexer_construct_function_object (parser_context_t *context_p, uint32_t extra_status_flags);
 void lexer_construct_regexp_object (parser_context_t *context_p, bool parse_only);
 bool lexer_compare_identifier_to_current (parser_context_t *context_p, const lexer_lit_location_t *right_ident_p);
-bool lexer_compare_raw_identifier_to_current (parser_context_t *context_p, const char *right_ident_p,
+bool lexer_compare_literal_to_identifier (parser_context_t *context_p, const char *identifier_p,
-                                              size_t right_ident_length);
+                                          size_t identifier_length);
+bool lexer_compare_literal_to_string (parser_context_t *context_p, const char *string_p, size_t string_length);
 uint8_t lexer_convert_binary_lvalue_token_to_binary (uint8_t token);
 
 /**

jerry-core/parser/js/js-parser-module.c

@@ -362,8 +362,7 @@ parser_module_parse_export_clause (parser_context_t *context_p) /**< parser cont
     uint16_t export_name_index = PARSER_MAXIMUM_NUMBER_OF_LITERALS;
 
     lexer_next_token (context_p);
-    if (context_p->token.type == LEXER_LITERAL
+    if (lexer_compare_literal_to_identifier (context_p, "as", 2))
-        && lexer_compare_raw_identifier_to_current (context_p, "as", 2))
     {
       lexer_next_token (context_p);
 
@@ -415,8 +414,7 @@ parser_module_parse_export_clause (parser_context_t *context_p) /**< parser cont
       lexer_next_token (context_p);
     }
 
-    if (context_p->token.type == LEXER_LITERAL
+    if (lexer_compare_literal_to_identifier (context_p, "from", 4))
-        && lexer_compare_raw_identifier_to_current (context_p, "from", 4))
     {
       parser_raise_error (context_p, PARSER_ERR_RIGHT_BRACE_EXPECTED);
     }
@@ -455,8 +453,7 @@ parser_module_parse_import_clause (parser_context_t *context_p) /**< parser cont
     uint16_t local_name_index = PARSER_MAXIMUM_NUMBER_OF_LITERALS;
 
     lexer_next_token (context_p);
-    if (context_p->token.type == LEXER_LITERAL
+    if (lexer_compare_literal_to_identifier (context_p, "as", 2))
-        && lexer_compare_raw_identifier_to_current (context_p, "as", 2))
     {
       lexer_next_token (context_p);
 
@@ -508,8 +505,7 @@ parser_module_parse_import_clause (parser_context_t *context_p) /**< parser cont
       lexer_next_token (context_p);
     }
 
-    if (context_p->token.type == LEXER_LITERAL
+    if (lexer_compare_literal_to_identifier (context_p, "from", 4))
-        && lexer_compare_raw_identifier_to_current (context_p, "from", 4))
     {
       parser_raise_error (context_p, PARSER_ERR_RIGHT_BRACE_EXPECTED);
     }

jerry-core/parser/js/js-parser-scanner.c

@@ -720,7 +720,7 @@ parser_scan_until (parser_context_t *context_p, /**< context */
           context_p->token.type = LEXER_KEYW_IN;
           return;
         }
-        else if (type == LEXER_LITERAL && lexer_compare_raw_identifier_to_current (context_p, "of", 2))
+        else if (lexer_compare_literal_to_identifier (context_p, "of", 2))
         {
           parser_stack_pop_uint8 (context_p);
           context_p->token.type = LEXER_LITERAL_OF;
@@ -788,13 +788,13 @@ parser_scan_until (parser_context_t *context_p, /**< context */
           break;
         }
 
-        if (lexer_compare_raw_identifier_to_current (context_p, "static", 6))
+        if (lexer_compare_literal_to_identifier (context_p, "static", 6))
         {
           lexer_next_token (context_p);
         }
 
-        if (lexer_compare_raw_identifier_to_current (context_p, "get", 3)
+        if (lexer_compare_literal_to_identifier (context_p, "get", 3)
-            || lexer_compare_raw_identifier_to_current (context_p, "set", 3))
+            || lexer_compare_literal_to_identifier (context_p, "set", 3))
         {
           lexer_next_token (context_p);
         }

jerry-core/parser/js/js-parser-statm.c

@@ -1884,12 +1884,6 @@ parser_parse_import_statement (parser_context_t *context_p) /**< parser context
 
       lexer_next_token (context_p);
 
-      if (context_p->token.type != LEXER_COMMA
-          && !lexer_compare_raw_identifier_to_current (context_p, "from", 4))
-      {
-        parser_raise_error (context_p, PARSER_ERR_FROM_COMMA_EXPECTED);
-      }
-
       if (context_p->token.type == LEXER_COMMA)
       {
         lexer_next_token (context_p);
@@ -1899,14 +1893,17 @@ parser_parse_import_statement (parser_context_t *context_p) /**< parser context
           parser_raise_error (context_p, PARSER_ERR_LEFT_BRACE_MULTIPLY_EXPECTED);
         }
       }
+      else if (!lexer_compare_literal_to_identifier (context_p, "from", 4))
+      {
+        parser_raise_error (context_p, PARSER_ERR_FROM_COMMA_EXPECTED);
+      }
     }
 
     if (context_p->token.type == LEXER_MULTIPLY)
     {
       /* NameSpaceImport*/
       lexer_next_token (context_p);
-      if (context_p->token.type != LEXER_LITERAL
+      if (!lexer_compare_literal_to_identifier (context_p, "as", 2))
-          || !lexer_compare_raw_identifier_to_current (context_p, "as", 2))
       {
         parser_raise_error (context_p, PARSER_ERR_AS_EXPECTED);
       }
@@ -1942,7 +1939,7 @@ parser_parse_import_statement (parser_context_t *context_p) /**< parser context
       parser_module_parse_import_clause (context_p);
     }
 
-    if (context_p->token.type != LEXER_LITERAL || !lexer_compare_raw_identifier_to_current (context_p, "from", 4))
+    if (!lexer_compare_literal_to_identifier (context_p, "from", 4))
     {
       parser_raise_error (context_p, PARSER_ERR_FROM_EXPECTED);
     }
@@ -2035,8 +2032,7 @@ parser_parse_export_statement (parser_context_t *context_p) /**< context */
     case LEXER_MULTIPLY:
     {
       lexer_next_token (context_p);
-      if (!(context_p->token.type == LEXER_LITERAL
+      if (!lexer_compare_literal_to_identifier (context_p, "from", 4))
-            && lexer_compare_raw_identifier_to_current (context_p, "from", 4)))
       {
         parser_raise_error (context_p, PARSER_ERR_FROM_EXPECTED);
       }
@@ -2106,8 +2102,7 @@ parser_parse_export_statement (parser_context_t *context_p) /**< context */
     {
       parser_module_parse_export_clause (context_p);
 
-      if (context_p->token.type == LEXER_LITERAL
+      if (lexer_compare_literal_to_identifier (context_p, "from", 4))
-          && lexer_compare_raw_identifier_to_current (context_p, "from", 4))
       {
         lexer_next_token (context_p);
         parser_module_handle_module_specifier (context_p);

tests/jerry/es2015/for-of.js

@@ -52,6 +52,10 @@ var forOf =
   "   obj[prop] += 4;"
 parse (forOf)
 
+var forOf =
+  "for (var a \"of\" []) {}"
+parse (forOf)
+
 checkError(5)
 
 var obj = {}