twister: Add --keep-artifacts option

Introduce a new command-line option `--keep-artifacts` in twister that
allows users to specify which artifacts should be preserved
during test cleanup in addition to the default set.

Signed-off-by: Benjamin Cabé <benjamin@zephyrproject.org>
Co-authored-by: Anas Nashif <anas.nashif@intel.com>

scripts/pylib/twister/twisterlib/environment.py

@@ -578,6 +578,11 @@ structure in the main Zephyr tree: boards/<vendor>/<board_name>/""")
         which only removes artifacts of passing tests. If you wish to
         remove all artificats including those of failed tests, use 'all'.""")
 
+    parser.add_argument(
+        "--keep-artifacts", action="append", default=[],
+        help="""Keep specified artifacts when cleaning up at runtime. Multiple invocations
+        are possible."""
+    )
     test_xor_generator.add_argument(
         "-N", "--ninja", action="store_true",
         default=not any(a in sys.argv for a in ("-k", "--make")),

scripts/pylib/twister/twisterlib/runner.py

@@ -1207,7 +1207,7 @@ class ProjectBuilder(FilterBuilder):
                     mode == "passed"
                     or (mode == "all" and self.instance.reason != "CMake build failure")
                 ):
-                    self.cleanup_artifacts()
+                    self.cleanup_artifacts(self.options.keep_artifacts)
             except StatusAttributeError as sae:
                 logger.error(str(sae))
                 self.instance.status = TwisterStatus.ERROR