add check root dir

colcon_core/verb/__init__.py

@@ -11,6 +11,8 @@
 from colcon_core.plugin_system import order_extensions_by_name
 
 logger = colcon_logger.getChild(__name__)
+DEFAULT_START_PATH = Path(os.path.abspath(os.getcwd()))
+MARKER_NAME = '.colcon_root'
 
 
 class VerbExtensionPoint:
@@ -124,6 +126,34 @@ def check_and_mark_install_layout(install_base, *, merge_install):
     marker_path.write_text(this_install_layout + '\n')
 
 
+def check_and_mark_colcon_root(start_path):
+    """
+    Check the marker file for root workspace, otherwise create it.
+
+    The marker filename is `.colcon_root`.
+
+    :param str start_path: The path where verb is invoked
+    :raises RuntimeError: if marker file is found in parent directory
+    """
+    current_path = start_path
+    home_path = Path(os.path.abspath(os.sep))
+    while current_path != home_path:
+        marker_path = current_path / MARKER_NAME
+        if marker_path.is_file():
+            if current_path != start_path:
+                raise RuntimeError(
+                    "'{start_path}' is not marked as the root directory. "
+                    "Please go to '{current_path}'. "
+                    'If you want to mark current path as root directory, '
+                    "please remove the '{MARKER_NAME}' file "
+                    "in '{current_path}'.".format_map(locals()))
+            return
+        else:
+            current_path = current_path.parent
+    marker_path = start_path / MARKER_NAME
+    marker_path.write_text('\n')
+
+
 def update_object(
     object_, key, value, package_name, argument_type, value_source
 ):

colcon_core/verb/build.py

@@ -26,6 +26,8 @@
 from colcon_core.task import TaskContext
 from colcon_core.verb import check_and_mark_build_tool
 from colcon_core.verb import check_and_mark_install_layout
+from colcon_core.verb import check_and_mark_colcon_root
+from colcon_core.verb import DEFAULT_START_PATH
 from colcon_core.verb import logger
 from colcon_core.verb import update_object
 from colcon_core.verb import VerbExtensionPoint
@@ -49,7 +51,7 @@ def __init__(self, pkg, args, *, additional_destinations=None):
         self.build_base = os.path.abspath(os.path.join(
             os.getcwd(), args.build_base, pkg.name))
         self.install_base = os.path.abspath(os.path.join(
-            os.getcwd(), args.install_base))
+            os.getcwd()))
         self.merge_install = args.merge_install
         if not args.merge_install:
             self.install_base = os.path.join(
@@ -116,6 +118,7 @@ def add_arguments(self, *, parser):  # noqa: D102
         self.task_argument_destinations = decorated_parser.get_destinations()
 
     def main(self, *, context):  # noqa: D102
+        check_and_mark_colcon_root(DEFAULT_START_PATH)
         check_and_mark_build_tool(context.args.build_base)
         check_and_mark_install_layout(
             context.args.install_base,

colcon_core/verb/test.py

@@ -23,6 +23,8 @@
 from colcon_core.task import TaskContext
 from colcon_core.verb import check_and_mark_build_tool
 from colcon_core.verb import check_and_mark_install_layout
+from colcon_core.verb import check_and_mark_colcon_root
+from colcon_core.verb import DEFAULT_START_PATH
 from colcon_core.verb import update_object
 from colcon_core.verb import VerbExtensionPoint
 
@@ -130,6 +132,7 @@ def add_arguments(self, *, parser):  # noqa: D102
             'retest_until_fail'
 
     def main(self, *, context):  # noqa: D102
+        check_and_mark_colcon_root(DEFAULT_START_PATH)
         check_and_mark_build_tool(context.args.build_base)
         check_and_mark_install_layout(
             context.args.install_base,