Use deferral mechanism for cfg file options

Fixes #3162

mitmproxy/optmanager.py

@@ -217,6 +217,10 @@ class OptManager:
                 self.changed.send(self, updated=updated)
         return unknown
 
+    def update_defer(self, **kwargs):
+        unknown = self.update_known(**kwargs)
+        self._deferred.update(unknown)
+
     def update(self, **kwargs):
         u = self.update_known(**kwargs)
         if u:
@@ -494,26 +498,21 @@ def parse(text):
     return data
 
 
-def load(opts, text):
+def load(opts: OptManager, text: str) -> None:
     """
         Load configuration from text, over-writing options already set in
         this object. May raise OptionsError if the config file is invalid.
-
-        Returns a dictionary of all unknown options.
     """
     data = parse(text)
-    return opts.update_known(**data)
+    opts.update_defer(**data)
 
 
-def load_paths(opts, *paths):
+def load_paths(opts: OptManager, *paths: str) -> None:
     """
         Load paths in order. Each path takes precedence over the previous
         path. Paths that don't exist are ignored, errors raise an
         OptionsError.
-
-        Returns a dictionary of unknown options.
     """
-    ret = {}
     for p in paths:
         p = os.path.expanduser(p)
         if os.path.exists(p) and os.path.isfile(p):
@@ -525,15 +524,14 @@ def load_paths(opts, *paths):
                         "Error reading %s: %s" % (p, e)
                     )
             try:
-                ret.update(load(opts, txt))
+                load(opts, txt)
             except exceptions.OptionsError as e:
                 raise exceptions.OptionsError(
                     "Error reading %s: %s" % (p, e)
                 )
-    return ret
 
 
-def serialize(opts, text, defaults=False):
+def serialize(opts: OptManager, text: str, defaults: bool = False) -> str:
     """
         Performs a round-trip serialization. If text is not None, it is
         treated as a previous serialization that should be modified
@@ -554,7 +552,7 @@ def serialize(opts, text, defaults=False):
     return ruamel.yaml.round_trip_dump(data)
 
 
-def save(opts, path, defaults=False):
+def save(opts: OptManager, path: str, defaults: bool =False) -> None:
     """
         Save to path. If the destination file exists, modify it in-place.
 

mitmproxy/tools/main.py

@@ -93,7 +93,7 @@ def run(
         sys.exit(1)
     try:
         opts.confdir = args.confdir
-        unknown = optmanager.load_paths(
+        optmanager.load_paths(
             opts,
             os.path.join(opts.confdir, OPTIONS_FILE_NAME),
         )
@@ -109,7 +109,6 @@ def run(
             server = proxy.server.DummyServer(pconf)
 
         master.server = server
-        opts.update_known(**unknown)
         if args.options:
             print(optmanager.dump_defaults(opts))
             sys.exit(0)

test/mitmproxy/test_optmanager.py

@@ -269,11 +269,13 @@ def test_serialize():
 
     t = "# a comment"
     optmanager.load(o2, t)
-    assert optmanager.load(o2, "foobar: '123'") == {"foobar": "123"}
+    optmanager.load(o2, "foobar: '123'")
+    assert o2._deferred == {"foobar": "123"}
 
     t = ""
     optmanager.load(o2, t)
-    assert optmanager.load(o2, "foobar: '123'") == {"foobar": "123"}
+    optmanager.load(o2, "foobar: '123'")
+    assert o2._deferred == {"foobar": "123"}
 
 
 def test_serialize_defaults():
@@ -297,7 +299,8 @@ def test_saving(tmpdir):
 
     with open(dst, 'a') as f:
         f.write("foobar: '123'")
-    assert optmanager.load_paths(o, dst) == {"foobar": "123"}
+    optmanager.load_paths(o, dst)
+    assert o._deferred == {"foobar": "123"}
 
     with open(dst, 'a') as f:
         f.write("'''")