[tor-commits] [stem/master] Resilience to 'Tor' prefix in 'GETINFO version'

[atagar at torproject.org]

commit 3b8c9efa8546827fa7cc6f2d93bff6a5ccff6f12
Author: Damian Johnson <atagar at torproject.org>
Date:   Wed Jul 5 09:57:31 2017 -0700

    Resilience to 'Tor' prefix in 'GETINFO version'
    
    Spec mistakenly said 'GETINFO version' prefixed its response with 'Tor '. It
    didn't, so we changed this to a may clause...
    
      https://trac.torproject.org/projects/tor/ticket/20014
      https://gitweb.torproject.org/torspec.git/commit/?id=c5ff1b1
    
    If tor ever did provide a 'Tor' prefix we'd choke, so making ourselves
    resilient to that.
---
 docs/change_log.rst             | 1 +
 stem/control.py                 | 3 ++-
 test/unit/control/controller.py | 5 +++++
 3 files changed, 8 insertions(+), 1 deletion(-)

diff --git a/docs/change_log.rst b/docs/change_log.rst
index af697a5..7159288 100644
--- a/docs/change_log.rst
+++ b/docs/change_log.rst
@@ -55,6 +55,7 @@ The following are only available within Stem's `git repository
   * Tor change caused :func:`~stem.control.Controller.list_ephemeral_hidden_services` to provide empty strings if unset (:trac:`21329`)
   * Better error message when :func:`~stem.control.Controller.set_conf` fails due to an option being immutable
   * Failed to parse torrcs without a port on ipv6 exit policy entries
+  * Resilient to 'Tor' prefix in 'GETINFO version' result (:spec:`c5ff1b1`)
 
  * **Descriptors**
 
diff --git a/stem/control.py b/stem/control.py
index 6475af4..a88f6e0 100644
--- a/stem/control.py
+++ b/stem/control.py
@@ -1242,7 +1242,8 @@ class Controller(BaseController):
     version = self._get_cache('version')
 
     if not version:
-      version = stem.version.Version(self.get_info('version'))
+      version_str = self.get_info('version')
+      version = stem.version.Version(version_str[4:] if version_str.startswith('Tor ') else version_str)
       self._set_cache({'version': version})
 
     return version
diff --git a/test/unit/control/controller.py b/test/unit/control/controller.py
index 124c115..17ca2bf 100644
--- a/test/unit/control/controller.py
+++ b/test/unit/control/controller.py
@@ -73,6 +73,11 @@ class TestControl(unittest.TestCase):
       # Return a version without caching, so it will be the new version.
       self.assertEqual(version_2_2_object, self.controller.get_version())
 
+      # Spec says the getinfo response may optionally be prefixed by 'Tor '. In
+      # practice it doesn't but we should accept that.
+      get_info_mock.return_value = 'Tor 0.2.1.32'
+      self.assertEqual(version_2_1_object, self.controller.get_version())
+
       # Raise an exception in the get_info() call.
       get_info_mock.side_effect = InvalidArguments