Merge branch 'master' into fix-func-decl-invoke

Author: goto-bus-stop

CHANGELOG.md

@@ -0,0 +1,7 @@
+# static-eval Change Log
+All notable changes to this project will be documented in this file.
+This project adheres to [Semantic Versioning](http://semver.org/).
+
+## 2.0.4
+* Short-circuit evaluation in `&&` and `||` expressions. ([@RoboPhred](https://github.com/RoboPhred) in [#28](https://github.com/browserify/static-eval/pull/28))
+* Start tracking changes.

index.js

@@ -40,12 +40,30 @@ module.exports = function (ast, vars) {
         }
         else if (node.type === 'BinaryExpression' ||
                  node.type === 'LogicalExpression') {
+            var op = node.operator;
+
+            if (op === '&&') {
+                var l = walk(node.left);
+                if (l === FAIL) return FAIL;
+                if (!l) return l;
+                var r = walk(node.right);
+                if (r === FAIL) return FAIL;
+                return r;
+            }
+            else if (op === '||') {
+                var l = walk(node.left);
+                if (l === FAIL) return FAIL;
+                if (l) return l;
+                var r = walk(node.right);
+                if (r === FAIL) return FAIL;
+                return r;
+            }
+
             var l = walk(node.left, noExecute);
             if (l === FAIL) return FAIL;
             var r = walk(node.right, noExecute);
             if (r === FAIL) return FAIL;
 
-            var op = node.operator;
             if (op === '==') return l == r;
             if (op === '===') return l === r;
             if (op === '!=') return l != r;
@@ -62,8 +80,6 @@ module.exports = function (ast, vars) {
             if (op === '|') return l | r;
             if (op === '&') return l & r;
             if (op === '^') return l ^ r;
-            if (op === '&&') return l && r;
-            if (op === '||') return l || r;
 
             return FAIL;
         }

package.json

@@ -1,6 +1,6 @@
 {
   "name": "static-eval",
-  "version": "2.0.3",
+  "version": "2.0.4",
   "description": "evaluate statically-analyzable expressions",
   "main": "index.js",
   "dependencies": {

readme.markdown

@@ -4,7 +4,7 @@ evaluate statically-analyzable expressions
 
 [![testling badge](https://ci.testling.com/substack/static-eval.png)](https://ci.testling.com/substack/static-eval)
 
-[![build status](https://secure.travis-ci.org/substack/static-eval.png)](http://travis-ci.org/substack/static-eval)
+[![build status](https://secure.travis-ci.org/browserify/static-eval.png)](http://travis-ci.org/browserify/static-eval)
 
 # security
 

test/eval.js

@@ -136,6 +136,32 @@ test('constructor at runtime only', function(t) {
     t.equal(res, undefined);
 });
 
+test('short circuit evaluation AND', function(t) {
+    t.plan(1);
+
+    var variables = {
+        value: null
+    };
+    var src = 'value && value.func()';
+    var ast = parse(src).body[0].expression;
+    var res = evaluate(ast, variables);
+    t.equals(res, null);
+})
+
+test('short circuit evaluation OR', function(t) {
+    t.plan(1);
+
+    var fnInvoked = false;
+    var variables = {
+        value: true,
+        fn: function() { fnInvoked = true}
+    };
+    var src = 'value || fn()';
+    var ast = parse(src).body[0].expression;
+    evaluate(ast, variables);
+    t.equals(fnInvoked, false);
+})
+
 test('function declaration does not invoke CallExpressions', function(t) {
     t.plan(1);