Merge branch '1.1' into 1.2

docs/usage/execution.rst

@@ -384,11 +384,29 @@ which is implemented similarly to the abovementioned ``hosts`` and ``roles``
 per-task kwargs, in that it is stripped from the actual task invocation. This
 example would have the same result as the global exclude above::
 
-    $ fab -R myrole mytask:exclude_hosts="host2;host5"
+    $ fab mytask:roles=myrole,exclude_hosts="host2;host5"
 
 Note that the host list is semicolon-separated, just as with the ``hosts``
 per-task argument.
 
+Combining exclusions
+~~~~~~~~~~~~~~~~~~~~
+
+Host exclusion lists, like host lists themselves, are not merged together
+across the different "levels" they can be declared in. For example, a global
+``-x`` option will not affect a per-task host list set with a decorator or
+keyword argument, nor will per-task ``exclude_hosts`` keyword arguments affect
+a global ``-H`` list.
+
+There is one minor exception to this rule, namely that CLI-level keyword
+arguments (``mytask:exclude_hosts=x,y``) **will** be taken into account when
+examining host lists set via ``@hosts`` or ``@roles``. Thus a task function
+decorated with ``@hosts('host1', 'host2')`` executed as ``fab
+taskname:exclude_hosts=host2`` will only run on ``host1``.
+
+As with the host list merging, this functionality is currently limited (partly
+to keep the implementation simple) and may be expanded in future releases.
+
 
 .. _failures:
 

fabric/main.py

@@ -518,8 +518,9 @@ def parse_arguments(arguments):
             for pair in _escape_split(',', argstr):
                 k, _, v = pair.partition('=')
                 if _:
-                    # Catch, interpret host/hosts/role/roles/exclude_hosts kwargs
-                    if k in ['host', 'hosts', 'role', 'roles','exclude_hosts']:
+                    # Catch, interpret host/hosts/role/roles/exclude_hosts
+                    # kwargs
+                    if k in ['host', 'hosts', 'role', 'roles', 'exclude_hosts']:
                         if k == 'host':
                             hosts = [v.strip()]
                         elif k == 'hosts':
@@ -567,11 +568,12 @@ def _merge(hosts, roles, exclude=[]):
         role_hosts += value
 
     # Return deduped combo of hosts and role_hosts, preserving order within
-    # them (vs using set(), which may lose ordering).
+    # them (vs using set(), which may lose ordering) and skipping hosts to be
+    # excluded.
     cleaned_hosts = _clean_hosts(list(hosts) + list(role_hosts))
     all_hosts = []
     for host in cleaned_hosts:
-        if host not in all_hosts:
+        if host not in all_hosts and host not in exclude:
             all_hosts.append(host)
     return all_hosts
 
@@ -594,9 +596,8 @@ def get_hosts(command, cli_hosts, cli_roles, cli_exclude_hosts):
     # Decorator-specific hosts/roles go next
     func_hosts = getattr(command, 'hosts', [])
     func_roles = getattr(command, 'roles', [])
-    func_exclude_hosts = getattr(command, 'exclude_hosts', [])
     if func_hosts or func_roles:
-        return _merge(func_hosts, func_roles, func_exclude_hosts)
+        return _merge(func_hosts, func_roles, cli_exclude_hosts)
     # Finally, the env is checked (which might contain globally set lists from
     # the CLI or from module-level code). This will be the empty list if these
     # have not been set -- which is fine, this method should return an empty
@@ -646,7 +647,8 @@ def main():
         for option in env_options:
             state.env[option.dest] = getattr(options, option.dest)
 
-        # Handle --hosts, --roles, --exclude-hosts (comma separated string => list)
+        # Handle --hosts, --roles, --exclude-hosts (comma separated string =>
+        # list)
         for key in ['hosts', 'roles', 'exclude_hosts']:
             if key in state.env and isinstance(state.env[key], basestring):
                 state.env[key] = state.env[key].split(',')

tests/test_main.py

@@ -179,8 +179,7 @@ def command():
     assert 'foo' not in get_hosts(command, [], [])
 
 
-@patched_env({'hosts': [' foo ', 'bar '], 'roles': [],
-        'exclude_hosts':[]})
+@patched_env({'hosts': [' foo ', 'bar '], 'roles': [], 'exclude_hosts': []})
 def test_hosts_stripped_env_hosts():
     """
     Make sure hosts defined in env.hosts are cleaned of extra spaces
@@ -231,6 +230,24 @@ def command():
     eq_(command.roles, role_list)
 
 
+#
+# Host exclusion
+#
+
+def dummy(): pass
+
+def test_get_hosts_excludes_cli_exclude_hosts_from_cli_hosts():
+    assert 'foo' not in get_hosts(dummy, ['foo', 'bar'], [], ['foo'])
+
+def test_get_hosts_excludes_cli_exclude_hosts_from_decorator_hosts():
+    assert 'foo' not in get_hosts(hosts('foo', 'bar')(dummy), [], [], ['foo'])
+
+@patched_env({'hosts': ['foo', 'bar'], 'exclude_hosts': ['foo']})
+def test_get_hosts_excludes_global_exclude_hosts_from_global_hosts():
+    assert 'foo' not in get_hosts(dummy, [], [], [])
+
+
+
 #
 # Basic role behavior
 #