sambacc: fix join interactive test

Fix how the Joiner and the test for interactive login was using stdin.
When the test was run without pytest capturing the stdio, the test would
hang waiting on input. This behavior was incorrect. Add a hook to the
Joiner for the unit tests to use so that the stdin of the interactive
join command can be manipulated.

Signed-off-by: John Mulligan <[email protected]>

Author: phlogistonjohn

sambacc/join.py

@@ -169,6 +169,9 @@ def _read_from(self, path: str) -> UserPass:
             raise JoinError("invalid file content: invalid password")
         return upass
 
+    def _interactive_input(self) -> typing.Optional[typing.IO]:
+        return None
+
     def _join(self, upass: UserPass, dns_updates: bool = False) -> None:
         args = []
         if not dns_updates:
@@ -177,7 +180,7 @@ def _join(self, upass: UserPass, dns_updates: bool = False) -> None:
 
         if upass.password is _PROMPT:
             cmd = list(self._net_ads_join[args])
-            proc = subprocess.Popen(cmd)
+            proc = subprocess.Popen(cmd, stdin=self._interactive_input())
         else:
             cmd = list(self._net_ads_join[args])
             proc = subprocess.Popen(cmd, stdin=subprocess.PIPE)

tests/test_join.py

@@ -45,8 +45,14 @@ class TestJoiner(sambacc.join.Joiner):
         _net_ads_join = samba_cmds.SambaCommand(fake_net_script)["ads", "join"]
         path = tmp_path
         logpath = data_path / "log"
+        _nullfh = None
 
-    return TestJoiner()
+        def _interactive_input(self):
+            return self._nullfh
+
+    with open(os.devnull, "rb") as dnull:
+        TestJoiner._null = dnull
+        yield TestJoiner()
 
 
 def test_no_sources(testjoiner):