Fix bug 737431 - Destructuring assignment doesn't work in expression …

…closures parameters. This creates a body node for expression closures, allowing extra code for destructuring parameters to be handled properly.
meh-uk · Mar 20, 2012 · 4607754 · 4607754
1 parent 6722b41
commit 4607754
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Showing 4 changed files with 80 additions and 46 deletions.
diff --git a/src/org/mozilla/javascript/IRFactory.java b/src/org/mozilla/javascript/IRFactory.java
@@ -962,14 +962,15 @@ private Node transformRegExp(RegExpLiteral node) {
     }
 
     private Node transformReturn(ReturnStatement node) {
-        if (Boolean.TRUE.equals(node.getProp(Node.EXPRESSION_CLOSURE_PROP))) {
+        boolean expClosure = Boolean.TRUE.equals(node.getProp(Node.EXPRESSION_CLOSURE_PROP));
+        if (expClosure) {
             decompiler.addName(" ");
         } else {
             decompiler.addToken(Token.RETURN);
         }
         AstNode rv = node.getReturnValue();
         Node value = rv == null ? null : transform(rv);
-        decompiler.addEOL(Token.SEMI);
+        if (!expClosure) decompiler.addEOL(Token.SEMI);
         return rv == null
             ? new Node(Token.RETURN, node.getLineno())
             : new Node(Token.RETURN, value, node.getLineno());

diff --git a/src/org/mozilla/javascript/Parser.java b/src/org/mozilla/javascript/Parser.java
@@ -619,11 +619,13 @@ private AstRoot parse() throws IOException
     private AstNode parseFunctionBody()
         throws IOException
     {
+        boolean isExpressionClosure = false;
         if (!matchToken(Token.LC)) {
             if (compilerEnv.getLanguageVersion() < Context.VERSION_1_8) {
                 reportError("msg.no.brace.body");
+            } else {
+                isExpressionClosure = true;
             }
-            return parseFunctionBodyExpr();
         }
         ++nestingOfFunction;
         int pos = ts.tokenBeg;
@@ -635,32 +637,41 @@ private AstNode parseFunctionBody()
 
         pn.setLineno(ts.lineno);
         try {
-            bodyLoop: for (;;) {
-                AstNode n;
-                int tt = peekToken();
-                switch (tt) {
-                  case Token.ERROR:
-                  case Token.EOF:
-                  case Token.RC:
-                    break bodyLoop;
-
-                  case Token.FUNCTION:
-                    consumeToken();
-                    n = function(FunctionNode.FUNCTION_STATEMENT);
-                    break;
-                  default:
-                    n = statement();
-                    if (inDirectivePrologue) {
-                        String directive = getDirective(n);
-                        if (directive == null) {
-                            inDirectivePrologue = false;
-                        } else if (directive.equals("use strict")) {
-                            inUseStrictDirective = true;
-                        }
+            if (isExpressionClosure) {
+                ReturnStatement n = new ReturnStatement(ts.lineno);
+                n.setReturnValue(assignExpr());
+                // expression closure flag is required on both nodes
+                n.putProp(Node.EXPRESSION_CLOSURE_PROP, Boolean.TRUE);
+                pn.putProp(Node.EXPRESSION_CLOSURE_PROP, Boolean.TRUE);
+                pn.addStatement(n);
+            } else {
+                bodyLoop: for (;;) {
+                    AstNode n;
+                    int tt = peekToken();
+                    switch (tt) {
+                        case Token.ERROR:
+                        case Token.EOF:
+                        case Token.RC:
+                            break bodyLoop;
+
+                        case Token.FUNCTION:
+                            consumeToken();
+                            n = function(FunctionNode.FUNCTION_STATEMENT);
+                            break;
+                        default:
+                            n = statement();
+                            if (inDirectivePrologue) {
+                                String directive = getDirective(n);
+                                if (directive == null) {
+                                    inDirectivePrologue = false;
+                                } else if (directive.equals("use strict")) {
+                                    inUseStrictDirective = true;
+                                }
+                            }
+                            break;
                     }
-                    break;
+                    pn.addStatement(n);
                 }
-                pn.addStatement(n);
             }
         } catch (ParserException e) {
             // Ignore it
@@ -671,7 +682,7 @@ private AstNode parseFunctionBody()
 
         int end = ts.tokenEnd;
         getAndResetJsDoc();
-        if (mustMatchToken(Token.RC, "msg.no.brace.after.body"))
+        if (!isExpressionClosure && mustMatchToken(Token.RC, "msg.no.brace.after.body"))
             end = ts.tokenEnd;
         pn.setLength(end - pos);
         return pn;
@@ -751,22 +762,6 @@ private void  parseFunctionParams(FunctionNode fnNode)
         }
     }
 
-
-    private AstNode parseFunctionBodyExpr()
-        throws IOException
-    {
-        ++nestingOfFunction;
-        int lineno = ts.getLineno();
-        ReturnStatement n = new ReturnStatement(lineno);
-        n.putProp(Node.EXPRESSION_CLOSURE_PROP, Boolean.TRUE);
-        try {
-            n.setReturnValue(assignExpr());
-        } finally {
-            --nestingOfFunction;
-        }
-        return n;
-    }
-
     private FunctionNode function(int type)
         throws IOException
     {

diff --git a/src/org/mozilla/javascript/ast/FunctionNode.java b/src/org/mozilla/javascript/ast/FunctionNode.java
@@ -418,9 +418,9 @@ public String toSource(int depth) {
         }
         if (isExpressionClosure) {
             AstNode body = getBody();
-            if (body instanceof ReturnStatement) {
+            if (body.getLastChild() instanceof ReturnStatement) {
                 // omit "return" keyword, just print the expression
-                body = ((ReturnStatement) body).getReturnValue();
+                body = ((ReturnStatement) body.getLastChild()).getReturnValue();
                 sb.append(body.toSource(0));
                 if (functionType == FUNCTION_STATEMENT) {
                     sb.append(";");

diff --git a/testsrc/doctests/expressionclosure.doctest b/testsrc/doctests/expressionclosure.doctest
@@ -0,0 +1,38 @@
+js> version(180)
+0
+js> x = function(x) x;
+
+function (x) x
+
+js> x.toSource()
+(function (x) x)
+js> x(123) === 123
+true
+js> x = function([a, b]) a + b;
+
+function ([a, b]) a + b
+
+js> x([1, 2])
+3
+js> x.toSource()
+(function ([a, b]) a + b)
+js> function outer() {
+  >    var k = function(a) a + 1;
+  >    return function(b) k(b) * 2;
+  > }
+js> outer
+
+function outer() {
+    var k = function (a) a + 1;
+    return function (b) k(b) * 2;
+}
+
+js> outer()
+
+function (b) k(b) * 2
+
+js> outer()(4)
+10
+js> outer()(5)
+12
+