test.taddon: Add cycle() method, use it to test addons.intercept

mitmproxy/addons/intercept.py

@@ -19,11 +19,10 @@ class Intercept:
 
     def process_flow(self, f):
         if self.filt:
-            should_intercept = all(
+            should_intercept = all([
                 self.filt(f),
                 not f.request.is_replay,
-                f.reply.state == "handled"
-            )
+            ])
             if should_intercept:
                 f.intercept(ctx.master)
 

mitmproxy/controller.py

@@ -174,10 +174,10 @@ class Reply:
 
 class DummyReply(Reply):
     """
-    A reply object that is not connected to anything. In contrast to regular Reply objects,
-    DummyReply objects are reset to "unhandled" at the end of an handler so that they can be used
-    multiple times. Useful when we need an object to seem like it has a channel,
-    and during testing.
+    A reply object that is not connected to anything. In contrast to regular
+    Reply objects, DummyReply objects are reset to "unhandled" at the end of an
+    handler so that they can be used multiple times. Useful when we need an
+    object to seem like it has a channel, and during testing.
     """
     def __init__(self):
         super().__init__(None)

mitmproxy/test/taddons.py

@@ -1,6 +1,7 @@
 import mitmproxy.master
 import mitmproxy.options
 from mitmproxy import proxy
+from mitmproxy import events
 
 
 class context:
@@ -26,6 +27,19 @@ class context:
         self.wrapped = None
         return False
 
+    def cycle(self, addon, f):
+        """
+            Cycles the flow through the events for the flow. Stops if a reply
+            is taken (as in flow interception).
+        """
+        f.reply._state = "handled"
+        for evt, arg in events.event_sequence(f):
+            h = getattr(addon, evt, None)
+            if h:
+                h(arg)
+                if f.reply.state == "taken":
+                    return
+
     def configure(self, addon, **kwargs):
         """
             A helper for testing configure methods. Modifies the registered

test/mitmproxy/addons/test_intercept.py

@@ -3,6 +3,7 @@ from mitmproxy import options
 from mitmproxy import exceptions
 from mitmproxy.test import taddons
 from mitmproxy.test import tutils
+from mitmproxy.test import tflow
 
 
 class Options(options.Options):
@@ -23,3 +24,13 @@ def test_simple():
             r,
             intercept="~~"
         )
+
+        tctx.configure(r, intercept="~s")
+
+        f = tflow.tflow(resp=True)
+        tctx.cycle(r, f)
+        assert f.intercepted
+
+        f = tflow.tflow(resp=False)
+        tctx.cycle(r, f)
+        assert not f.intercepted