fix: clearing a timer inside its callback

fixes #30

Author: fent

lib/index.js

@@ -124,6 +124,7 @@ const timer = (type, clear, fn, ms) => {
     countdownStart = Date.now();
     nextTime = ms;
     fn();
+    if (done) return;
     if (type === setTimeout) {
       done = true;
       if (typeof finished === 'function') {

test/group-test.js

@@ -77,5 +77,26 @@ describe('Group', () => {
         done();
       }, 100);
     });
+
+    describe('Timer inside a callback', () => {
+      it('Timers are cleared', (done) => {
+        let called = false;
+        let a = group.setTimeout(() => {
+          called = true;
+          a.clear();
+        }, 10);
+        assert.equal(group.timers().length, 5);
+        mysetTimeout(() => {
+          assert.ok(called);
+          assert.equal(group.timers().length, 4);
+          mysetTimeout(() => {
+            assert.ok(!a.called);
+            assert.ok(b.called);
+            assert.ok(c.called);
+          }, 300);
+          done();
+        }, 10);
+      });
+    });
   });
 });