fix dash test runner

packages/tracker/meshnet_tracker/test_runner.py

@@ -57,6 +57,7 @@ DEFAULT_MAX_LOG_LINES = 4000
 _MAX_LINE_CHARS = 4000
 DEFAULT_COLLECT_TIMEOUT = 120.0
 DEFAULT_RUN_TIMEOUT = 1800.0
+PYTHON_ENV_VAR = "MESHNET_PYTHON"
 
 _NODE_ID_RE = re.compile(r"^[\w./\[\]:,= @-]+$")
 
@@ -98,6 +99,23 @@ def _real_inference_enabled() -> bool:
     return os.environ.get(REAL_INFERENCE_ENV_VAR) == "1"
 
 
+def _test_python() -> str:
+    """Return the project interpreter configured by the machine env file.
+
+    The tracker may run from a lightweight service environment while the test
+    suite needs the project's full environment (including SDK dependencies).
+    ``meshnet_tracker.cli`` loads ``.env.<hostname>`` before constructing the
+    server, so use its explicit interpreter selection for child pytest runs.
+    Direct users of ``TestRunManager`` retain the normal interpreter fallback.
+    """
+    configured = os.environ.get(PYTHON_ENV_VAR, "").strip()
+    if configured:
+        python = Path(configured).expanduser()
+        if python.is_file() and os.access(python, os.X_OK):
+            return str(python)
+    return sys.executable
+
+
 class TestRunManager:
     """Collects pytest node IDs and runs one fixed target at a time."""
 
@@ -145,7 +163,7 @@ class TestRunManager:
             if self._collected_at is not None and not refresh:
                 return self._collection_snapshot_locked()
 
-        cmd = [sys.executable, "-m", "pytest", "--collect-only", "-q", "-p", "no:cacheprovider"]
+        cmd = [_test_python(), "-m", "pytest", "--collect-only", "-q", "-p", "no:cacheprovider"]
         if not _real_inference_enabled():
             for name in sorted(
                 p.name for p in (self.repo_root / "tests").glob("test_real_*.py")
@@ -216,7 +234,7 @@ class TestRunManager:
         with self._lock:
             if self._run is not None and self._run["status"] == "running":
                 raise RunInProgressError("a test run is already in progress")
-            cmd = [sys.executable, "-m", "pytest", "-q", "-p", "no:cacheprovider", *pytest_args]
+            cmd = [_test_python(), "-m", "pytest", "-q", "-p", "no:cacheprovider", *pytest_args]
             self._stdout = deque(maxlen=self.max_log_lines)
             self._stderr = deque(maxlen=self.max_log_lines)
             process = subprocess.Popen(  # noqa: S603 — fixed argv, no shell