[nrf noup] Add --keep-previous argument to zap-generate

* Remove previous ZAP generated files.
* Add `-k`/`--keep-previous` argument to skip removing old files.

Signed-off-by: Adrian Gielniewski <adrian.gielniewski@nordicsemi.no>

Author: adigie

scripts/west/zap_generate.py

@@ -7,6 +7,7 @@
 import sys
 
 from textwrap import dedent
+from pathlib import Path
 
 from west import log
 from west.commands import CommandError, WestCommand
@@ -37,6 +38,7 @@ def do_add_parser(self, parser_adder):
         parser.add_argument('-m', '--matter-path', type=existing_dir_path,
                             default=DEFAULT_MATTER_PATH, help='Path to Matter SDK')
         parser.add_argument('-f', '--full', action='store_true', help='Generate full data model files')
+        parser.add_argument('-k', '--keep-previous', action='store_true', help='Keep previously generated files')
         return parser
 
     def build_command(self, zap_file_path, output_path, templates_path):
@@ -68,10 +70,12 @@ def do_run(self, args, unknown_args):
         # make sure that the generate.py script uses the proper zap_cli binary (handled by west)
         os.environ["ZAP_INSTALL_PATH"] = str(zap_installer.get_zap_cli_path().parent.absolute())
 
-
         # Make sure that output directory exists
         output_path.mkdir(exist_ok=True)
 
+        if not args.keep_previous:
+            self.clear_generated_files(output_path)
+
         self.check_call(self.build_command(zap_file_path, output_path, app_templates_path))
 
         if args.full:
@@ -81,3 +85,15 @@ def do_run(self, args, unknown_args):
             self.check_call(self.build_command(zap_file_path, output_path, templates_path))
 
         log.inf(f"Done. Files generated in {output_path}")
+
+    def clear_generated_files(self, path: Path):
+        log.inf("Clearing previously generated files:")
+        for file in path.iterdir():
+            if file.is_file():
+                with open(file, 'r') as f:
+                    for line in f.readlines():
+                        if "// THIS FILE IS GENERATED BY ZAP" in line:
+                            log.inf(f"\tRemoving {file}")
+                            file.unlink()
+                            break
+