Extract _generateSyntheticStacktrace method from captureMessage

Author: kamilogorek

src/raven.js

@@ -438,39 +438,7 @@ Raven.prototype = {
     );
 
     if (this._globalOptions.stacktrace || (options && options.stacktrace)) {
-      var ex;
-      // Generate a "synthetic" stack trace from this point.
-      // NOTE: If you are a Sentry user, and you are seeing this stack frame, it is NOT indicative
-      //       of a bug with Raven.js. Sentry generates synthetic traces either by configuration,
-      //       or if it catches a thrown object without a "stack" property.
-      try {
-        throw new Error(msg);
-      } catch (ex1) {
-        ex = ex1;
-      }
-
-      // null exception name so `Error` isn't prefixed to msg
-      ex.name = null;
-
-      options = objectMerge(
-        {
-          // fingerprint on msg, not stack trace (legacy behavior, could be
-          // revisited)
-          fingerprint: msg,
-          // since we know this is a synthetic trace, the top N-most frames
-          // MUST be from Raven.js, so mark them as in_app later by setting
-          // trimHeadFrames
-          trimHeadFrames: (options.trimHeadFrames || 0) + 1
-        },
-        options
-      );
-
-      var stack = TraceKit.computeStackTrace(ex);
-      var frames = this._prepareFrames(stack, options);
-      data.stacktrace = {
-        // Sentry expects frames oldest to newest
-        frames: frames.reverse()
-      };
+      data.stacktrace = this._generateSyntheticStacktrace(msg, options);
     }
 
     // Fire away!
@@ -1471,6 +1439,45 @@ Raven.prototype = {
     this._send(data);
   },
 
+  _generateSyntheticStacktrace: function(msg, options) {
+    options = options || {};
+
+    var ex;
+    // Generate a "synthetic" stack trace from this point.
+    // NOTE: If you are a Sentry user, and you are seeing this stack frame, it is NOT indicative
+    //       of a bug with Raven.js. Sentry generates synthetic traces either by configuration,
+    //       or if it catches a thrown object without a "stack" property.
+    try {
+      throw new Error(msg);
+    } catch (ex1) {
+      ex = ex1;
+    }
+
+    // null exception name so `Error` isn't prefixed to msg
+    ex.name = null;
+
+    options = objectMerge(
+      {
+        // fingerprint on msg, not stack trace (legacy behavior, could be
+        // revisited)
+        fingerprint: msg,
+        // since we know this is a synthetic trace, the top N-most frames
+        // MUST be from Raven.js, so mark them as in_app later by setting
+        // trimHeadFrames
+        trimHeadFrames: (options.trimHeadFrames || 0) + 1
+      },
+      options
+    );
+
+    var stack = TraceKit.computeStackTrace(ex);
+    var frames = this._prepareFrames(stack, options);
+    return {
+      // Sentry expects frames oldest to newest
+      // We also remove _generateSyntheticStacktrace call itself from the stack
+      frames: frames.slice(1).reverse()
+    };
+  },
+
   _trimPacket: function(data) {
     // For now, we only want to truncate the two different messages
     // but this could/should be expanded to just trim everything

test/raven.test.js

@@ -716,6 +716,15 @@ describe('globals', function() {
     });
   });
 
+  describe('generateSyntheticStacktrace', function() {
+    it('should return an object with generated frames', function() {
+      var stacktrace = Raven._generateSyntheticStacktrace('foo');
+
+      assert.isDefined(stacktrace.frames);
+      assert.isAbove(stacktrace.frames.length, 1);
+    });
+  });
+
   describe('send', function() {
     it('should build a good data payload', function() {
       this.sinon.stub(Raven, 'isSetup').returns(true);
@@ -2654,6 +2663,7 @@ describe('Raven (public API)', function() {
         }
 
         foo();
+
         var frames = Raven._send.lastCall.args[0].stacktrace.frames;
         assertSynthetic(frames);
       });
@@ -2668,6 +2678,7 @@ describe('Raven (public API)', function() {
         }
 
         foo();
+
         var frames = Raven._send.lastCall.args[0].stacktrace.frames;
         assertSynthetic(frames);
       });