incus connection: fix regex (#11347)

* incus connection: fix regex

* updates

* Apply suggestions from code review

* expand regexp capture

* add changelog frag

* Update plugins/connection/incus.py

* split arguments after command option

* Update plugins/connection/incus.py

* remove *() and split from the last command

* add tests, make small adjustments

* remove redundant strip()

* add more tests

* adjusted changelog fragment

tests/unit/plugins/connection/test_incus.py

@@ -0,0 +1,136 @@
+# Copyright (c) 2026, Alexei Znamensky <russoz@gmail.com>
+# GNU General Public License v3.0+ (see LICENSES/GPL-3.0-or-later.txt or https://www.gnu.org/licenses/gpl-3.0.txt)
+# SPDX-License-Identifier: GPL-3.0-or-later
+
+from __future__ import annotations
+
+import pytest
+import typing as t
+from io import StringIO
+
+from ansible.playbook.play_context import PlayContext
+from ansible.plugins.loader import connection_loader
+
+BUILD_CMD_TEST_CASES: list[dict[str, t.Any]] = [
+    dict(
+        id="sh simple",
+        input=dict(
+            cmd="""echo 123""",
+            shell="sh",
+        ),
+        output=["/bin/sh", "-c", "echo 123"],
+    ),
+    dict(
+        id="powershell simple",
+        input=dict(
+            cmd="""powershell -c My-Command1 -Param 'param' """,
+            shell="powershell",
+        ),
+        output=["powershell", "-c", "My-Command1 -Param 'param'"],
+    ),
+    dict(
+        id=r"D:\my path\powershell.exe simple",
+        input=dict(
+            cmd=r"""D:\my path\powershell.exe -c My-Command1 -Param 'param' """,
+            shell="powershell",
+        ),
+        output=[r"D:\my path\powershell.exe", "-c", "My-Command1 -Param 'param'"],
+    ),
+    dict(
+        id=r"\\127.0.0.1\share\powershell simple",
+        input=dict(
+            cmd=r"""\\127.0.0.1\share\powershell -c My-Command1 -Param 'param' """,
+            shell="powershell",
+        ),
+        output=[r"\\127.0.0.1\share\powershell", "-c", "My-Command1 -Param 'param'"],
+    ),
+    dict(
+        id=r"C:\powershell simple",
+        input=dict(
+            cmd=r"""C:\powershell -c My-Command1 -Param 'param' """,
+            shell="powershell",
+        ),
+        output=[r"C:\powershell", "-c", "My-Command1 -Param 'param'"],
+    ),
+    dict(
+        id=r'"C:\powershell" simple',
+        input=dict(
+            cmd=r""""C:\powershell" -c My-Command1 -Param 'param' """,
+            shell="cmd",  # the plugins does not care the shell type, as long as it is windows
+        ),
+        output=[r"C:\powershell", "-c", "My-Command1 -Param 'param'"],
+    ),
+    dict(
+        id="powershell multiline",
+        input=dict(
+            cmd=(
+                "powershell -ExecutionPolicy bypass -Command\n"
+                "My-Command1 \\\n"
+                "  -Param 'param';\n"
+                "My-Command2 \\\n"
+                "  -Param 'param'"
+            ),
+            shell="powershell",
+        ),
+        output=[
+            "powershell",
+            "-ExecutionPolicy",
+            "bypass",
+            "-Command",
+            "My-Command1 \\\n  -Param 'param';\nMy-Command2 \\\n  -Param 'param'",
+        ],
+    ),
+    dict(
+        id="cmd simple",
+        input=dict(
+            cmd="""CMD.EXE /C some-command /flag1 /flag2""",
+            shell="powershell",
+        ),
+        output=["CMD.EXE", "/C", "some-command /flag1 /flag2"],
+    ),
+    dict(
+        id=r"C:\cmd simple",
+        input=dict(
+            cmd=r"""C:\CMD.EXE /C some-command /flag1 /flag2""",
+            shell="powershell",
+        ),
+        output=[r"C:\CMD.EXE", "/C", "some-command /flag1 /flag2"],
+    ),
+    dict(
+        id=r'"C:\cmd" simple',
+        input=dict(
+            cmd=r""""C:\CMD" /c some-command /flag1 /flag2""",
+            shell="powershell",
+        ),
+        output=[r"C:\CMD", "/c", "some-command /flag1 /flag2"],
+    ),
+]
+
+
+BUILD_CMD_TEST_CASE_IDS: list[str] = [tc["id"] for tc in BUILD_CMD_TEST_CASES]
+
+
+@pytest.mark.parametrize("testcase", BUILD_CMD_TEST_CASES, ids=BUILD_CMD_TEST_CASE_IDS)
+def test_build_command(mocker, testcase):
+    mocker.patch("ansible.module_utils.common.process.get_bin_path").return_value = "/test/bin/incus"
+
+    play_context = PlayContext()
+    play_context.shell = testcase["input"].get("shell", "sh")
+    in_stream = StringIO()
+    conn = connection_loader.get("community.general.incus", play_context, in_stream)
+    conn.set_option("remote_addr", "server1")
+    conn.set_option("remote_user", "root")
+
+    cli_preamble = [
+        "/test/bin/incus",
+        "--project",
+        "default",
+        "exec",
+        *(["-T"] if play_context.shell in ["cmd", "powershell"] else []),
+        "local:server1",
+        "--",
+    ]
+
+    built = conn._build_command(testcase["input"]["cmd"])
+    tc_cmd = cli_preamble + testcase["output"]
+    assert built == tc_cmd, f"\n   built = {built}\ntestcase = {tc_cmd}"