Bug 568953 - Parser support for module declarations; r=jorendorff

js/src/frontend/Parser.cpp

@@ -412,7 +412,7 @@ FunctionBox::FunctionBox(JSContext *cx, ObjectBox* traceListHead, JSFunction *fu
                 inWith = true;
             scope = scope->enclosingScope();
         }
-    } else {
+    } else if (outerpc->sc->isFunctionBox()) {
         // This is like the above case, but for more deeply nested functions.
         // For example:
         //
@@ -1845,6 +1845,41 @@ Parser::functionArgsAndBody(ParseNode *pn, HandleFunction fun, HandlePropertyNam
     return true;
 }
 
+ParseNode *
+Parser::moduleDecl()
+{
+    JS_ASSERT(tokenStream.currentToken().name() == context->runtime->atomState.module);
+    if (!((pc->sc->isGlobalSharedContext() || pc->sc->isModuleBox()) && pc->atBodyLevel()))
+    {
+        reportError(NULL, JSMSG_MODULE_STATEMENT);
+        return NULL;
+    }
+
+    ParseNode *pn = CodeNode::create(PNK_MODULE, this);
+    if (!pn)
+        return NULL;
+    JS_ALWAYS_TRUE(tokenStream.matchToken(TOK_STRING));
+    RootedAtom atom(context, tokenStream.currentToken().atom());
+    Module *module = js_NewModule(context, atom);
+    if (!module)
+        return NULL;
+    ModuleBox *modulebox = newModuleBox(module, pc);
+    if (!modulebox)
+        return NULL;
+    pn->pn_modulebox = modulebox;
+
+    ParseContext modulepc(this, modulebox, pc->staticLevel + 1, pc->blockidGen);
+    if (!modulepc.init())
+        return NULL;
+    MUST_MATCH_TOKEN(TOK_LC, JSMSG_CURLY_BEFORE_MODULE);
+    pn->pn_body = statements();
+    if (!pn->pn_body)
+        return NULL;
+    MUST_MATCH_TOKEN(TOK_RC, JSMSG_CURLY_AFTER_MODULE);
+
+    return pn;
+}
+
 ParseNode *
 Parser::functionStmt()
 {
@@ -4047,6 +4082,13 @@ Parser::statement()
       case TOK_ERROR:
         return NULL;
 
+      case TOK_NAME:
+        if (tokenStream.currentToken().name() == context->names().module &&
+            tokenStream.peekTokenSameLine(TSF_OPERAND) == TOK_STRING)
+        {
+            return moduleDecl();
+        }
+
       default:
         return expressionStatement();
     }

js/src/frontend/Parser.h

@@ -374,6 +374,7 @@ struct Parser : private AutoGCRooter
      * Some parsers have two versions:  an always-inlined version (with an 'i'
      * suffix) and a never-inlined version (with an 'n' suffix).
      */
+    ParseNode *moduleDecl();
     ParseNode *functionStmt();
     ParseNode *functionExpr();
     ParseNode *statements(bool *hasFunctionStmt = NULL);

js/src/js.msg

@@ -388,3 +388,6 @@ MSG_DEF(JSMSG_INVALID_CURRENCY_CODE,  334, 1, JSEXN_RANGEERR, "invalid currency
 MSG_DEF(JSMSG_UNDEFINED_CURRENCY,     335, 0, JSEXN_TYPEERR, "undefined currency in NumberFormat() with currency style")
 MSG_DEF(JSMSG_INVALID_TIME_ZONE,      336, 1, JSEXN_RANGEERR, "invalid time zone in DateTimeFormat(): {0}")
 MSG_DEF(JSMSG_DATE_NOT_FINITE,        337, 0, JSEXN_RANGEERR, "date value is not finite in DateTimeFormat.format()")
+MSG_DEF(JSMSG_MODULE_STATEMENT,       338, 0, JSEXN_SYNTAXERR, "module declarations may only appear at the top level of a program or module body")
+MSG_DEF(JSMSG_CURLY_BEFORE_MODULE,    339, 0, JSEXN_SYNTAXERR, "missing { before module body")
+MSG_DEF(JSMSG_CURLY_AFTER_MODULE,     340, 0, JSEXN_SYNTAXERR, "missing } after module body")

js/src/vm/CommonPropertyNames.h

@@ -87,6 +87,7 @@
     macro(lookupGetter, lookupGetter, "__lookupGetter__") \
     macro(lookupSetter, lookupSetter, "__lookupSetter__") \
     macro(message, message, "message") \
+    macro(module, module, "module") \
     macro(multiline, multiline, "multiline") \
     macro(name, name, "name") \
     macro(NaN, NaN, "NaN") \