Let auto-expand work in -c/-f mode, where there is no prompt

changelog.rst

@@ -6,6 +6,15 @@ Features:
 * Add a ``\service`` prompt token for connections made using ``service=...``
   or ``PGSERVICE``. For example, set ``prompt = '\service> '``.
 
+Bug fixes:
+----------
+* ``--auto-vertical-output``, ``\x auto`` and ``auto_expand`` in the config work
+  in ``-c``/``-f`` mode. The terminal width was read from the prompt, which
+  those modes never build, so every statement failed with ``'NoneType' object
+  has no attribute 'output'``. Without a prompt the terminal is asked directly,
+  and only when the output is one: a pipe or a file gets the plain table, as
+  with psql's ``\x auto``.
+
 4.7.1 (2026-09-20)
 ==================
 

pgcli/main.py

@@ -1314,6 +1314,19 @@ def _limit_output(self, cur):
 
         return new_cur, new_status
 
+    def _output_width(self):
+        """Columns available to auto-expand into, or None when it must not apply.
+
+        In -c/-f mode no prompt is ever built, so the terminal is asked
+        directly. psql's \\x auto only expands when the output is a terminal:
+        a pipe or a file gets the plain table whatever its width.
+        """
+        if self.prompt_app:
+            return self.prompt_app.output.get_size().columns
+        if sys.stdout.isatty():
+            return shutil.get_terminal_size().columns
+        return None
+
     def _evaluate_command(self, text):
         """Used to run a command entered by the user during CLI operation
         (Puts the E in REPL)
@@ -1356,7 +1369,7 @@ def _evaluate_command(self, text):
                 cur, status = self._limit_output(cur)
 
             if self.pgspecial.auto_expand or self.auto_expand:
-                max_width = self.prompt_app.output.get_size().columns
+                max_width = self._output_width()
             else:
                 max_width = None
 

tests/test_main.py

@@ -1087,3 +1087,29 @@ def test_connect_timeout_config_value_must_be_a_number(tmpdir):
         f.write("[main]\nconnect_timeout = soon\n")
     with pytest.raises(ValueError):
         PGCli(pgclirc_file=rc)
+
+
+@dbtest
+def test_auto_expand_works_without_a_prompt(executor):
+    # -c/-f mode never builds the prompt, and --auto-vertical-output (or
+    # \x auto, or auto_expand in the config) then failed every statement
+    # with "'NoneType' object has no attribute 'output'". Output that is not
+    # a terminal gets the plain table, as psql's \x auto does.
+    cli = PGCli(pgexecute=executor, auto_vertical_output=True)
+    assert cli.prompt_app is None
+    with mock.patch("pgcli.main.sys.stdout.isatty", return_value=False):
+        output, query = cli._evaluate_command("select 1 as a, 2 as b")
+    assert query.successful
+    assert not any("RECORD 1" in line for line in output)
+
+
+@dbtest
+def test_auto_expand_without_a_prompt_asks_the_terminal(executor):
+    cli = PGCli(pgexecute=executor, auto_vertical_output=True)
+    with (
+        mock.patch("pgcli.main.sys.stdout.isatty", return_value=True),
+        mock.patch("pgcli.main.shutil.get_terminal_size", return_value=os.terminal_size((5, 24))),
+    ):
+        output, query = cli._evaluate_command("select 1 as a, 2 as b")
+    assert query.successful
+    assert any("RECORD 1" in line for line in output)