Merge pull request #2956 from kira0204/test-for-2850

Test for #2850

mitmproxy/command.py

@@ -1,5 +1,5 @@
 """
-    This module manges and invokes typed commands.
+    This module manages and invokes typed commands.
 """
 import inspect
 import types
@@ -131,7 +131,12 @@ class CommandManager(mitmproxy.types._CommandBase):
         for i in dir(addon):
             if not i.startswith("__"):
                 o = getattr(addon, i)
-                if hasattr(o, "command_path"):
+                try:
+                    is_command = hasattr(o, "command_path")
+                except Exception:
+                    pass  # hasattr may raise if o implements __getattr__.
+                else:
+                    if is_command:
                         self.add(o.command_path, o)
 
     def add(self, path: str, func: typing.Callable):

test/mitmproxy/test_command.py

@@ -309,6 +309,31 @@ class TDec:
         pass
 
 
+class TAttr:
+    def __getattr__(self, item):
+        raise IOError
+
+
+class TCmds(TAttr):
+    def __init__(self):
+        self.TAttr = TAttr()
+
+    @command.command("empty")
+    def empty(self) -> None:
+        pass
+
+
+def test_collect_commands():
+    """
+        This tests for the error thrown by hasattr()
+    """
+    with taddons.context() as tctx:
+        c = command.CommandManager(tctx.master)
+        a = TCmds()
+        c.collect_commands(a)
+        assert "empty" in c.commands
+
+
 def test_decorator():
     with taddons.context() as tctx:
         c = command.CommandManager(tctx.master)