Enable maxFrames config option

Matt Loring · Matt Loring · commit 08fb68ce505e · 2016-01-21T16:31:46.000-08:00
diff --git a/config.js b/config.js
@@ -41,8 +41,7 @@ module.exports = {
 
     // Maximum number of stack frames to capture data for. The limit is aimed
     // to reduce overall capture time
-    // TODO: implement this
-    //maxFrames: 20,
+    maxFrames: 20,
 
     // Only collect locals and arguments on a few top frames. For the rest
     // only collect the source location
diff --git a/lib/state.js b/lib/state.js
@@ -180,10 +180,11 @@ StateResolver.prototype.trimVariableTable_ = function(fromIndex, frames) {
 
 StateResolver.prototype.resolveFrames_ = function() {
   // TODO(ofrobots): only gather variables for top n frames (python: 5)
-  // TODO(ofrobots): Do not gather the full stack trace (python: 20)
 
   var frames = [];
-  for (var i = 0; i < this.state_.frameCount(); i++) {
+  var frameCount = Math.min(this.state_.frameCount(),
+    this.config_.capture.maxFrames);
+  for (var i = 0; i < frameCount; i++) {
     var frame = this.state_.frame(i);
     if (this.shouldFrameBeResolved_(frame)) {
       var resolveVars = i < this.config_.capture.maxExpandFrames;
diff --git a/test/test-v8debugapi.js b/test/test-v8debugapi.js
@@ -336,6 +336,30 @@ describe('v8debugapi', function() {
       });
     });
 
+    it('should capture correct frame count', function(done) {
+      // clone a clean breakpointInFoo
+      var bp  = {id: breakpointInFoo.id, location: breakpointInFoo.location};
+      var oldMax = config.capture.maxFrames;
+      config.capture.maxFrames = 1;
+      api.set(bp, function(err) {
+        assert.ifError(err);
+        api.wait(bp, function(err) {
+          assert.ifError(err);
+          assert.ok(bp.stackFrames);
+          assert.equal(bp.stackFrames.length, config.capture.maxFrames);
+          var topFrame = bp.stackFrames[0];
+          assert.ok(topFrame);
+          assert.equal(topFrame['function'], 'foo');
+          assert.equal(topFrame.arguments[0].name, 'n');
+          assert.equal(topFrame.arguments[0].value, '2');
+          api.clear(bp);
+          config.capture.maxFrames = oldMax;
+          done();
+        });
+      process.nextTick(function() {foo(2);});
+      });
+    });
+
     it('should capture state with watch expressions', function(done) {
       // clone a clean breakpointInFoo
       var bp  = {
