prfun - npm Package Compare versions

Comparing version 1.0.1 to 1.0.2

CHANGELOG.md

@@ -0,1 +1,5 @@
+# prfun 1.0.2 (2014-11-06)
+
+* Fix potential resource leak in `Promise#timeout`.
+
 # prfun 1.0.1 (2014-09-25)
@@ -2,0 +6,0 @@

lib/index.js

@@ -292,2 +292,8 @@ // Utility functions for ES6 Promises.
 
+  var makeRejector = function(reject, message, ms) {
+    // create this function in an outer scope so that we don't inadvertently
+    // keep a reference to the promise here.  Perhaps this is overkill.
+    var id = setTimeout(function() { reject(new TimeoutError(message)); }, ms);
+    return function() { clearTimeout(id); };
+  };
   Promise.prototype.timeout = function(ms, message) {
@@ -298,3 +304,4 @@ var P = this.constructor || Promise;
       promise.then(resolve, reject);
-      setTimeout(function() { reject(new TimeoutError(message)); }, ms);
+      var cleanup = makeRejector(reject, message, ms);
+      promise.then(cleanup, cleanup);
     });
@@ -301,0 +308,0 @@ };

package.json

 {
   "name": "prfun",
-  "version": "1.0.1",
+  "version": "1.0.2",
   "description": "Helper functions for ES6 promises",
@@ -5,0 +5,0 @@ "main": "index.js",

README.md

@@ -945,4 +945,21 @@ # prfun
 
-`Promise#finally` works like [Q's finally method](https://github.com/kriskowal/q/wiki/API-Reference#wiki-promisefinallycallback).
+`Promise#finally` works like [Q's finally method](https://github.com/kriskowal/q/wiki/API-Reference#wiki-promisefinallycallback), unless `callback` returns a rejected promise.
 
+Note that the parallel with synchronous `finally` is not exact:
+```js
+// as expected:
+(function() { try { return 1; } finally { throw "2"; } })(); // throws "2"
+Promise.resolve(1).finally(function() { throw "2"; }); // rejects with "2"
+
+// but:
+(function() { try { return 1; } finally { return 2; } })(); // returns 2
+Promise.resolve(1).finally(function() { return 2; }); // resolves to '1'
+
+// compare:
+(function() { try { return 1; } finally { 2; } })(); // returns 1
+```
+
+This asymmetry is because the `Promise` API can't distinguish the `return`
+statement from an expression evaluating to a value.
+
 <hr>
@@ -949,0 +966,0 @@

No alert changes

Improved metrics

Total package byte prevSize

191593

0.57%

Lines of code

4485

0.16%

Number of lines in readme file

1434

1.2%

No dependency changes