Add --prune option to cbi-tree

Excludes unused files from the output and computed metrics.

Signed-off-by: John Pennycook <john.pennycook@intel.com>

Author: Pennycook

codebasin/report.py

@@ -748,7 +748,9 @@ def write_to(self, stream: TextIO):
 def files(
     codebase: CodeBase,
     state: ParserState | None = None,
+    *,
     stream: TextIO = sys.stdout,
+    prune: bool = False,
 ):
     """
     Produce a file tree representing the code base.
@@ -787,6 +789,11 @@ def files(
             ):
                 platform = frozenset(association[node])
                 setmap[platform] += node.num_lines
+        if prune:
+            # Prune unused files from the tree.
+            platforms = set().union(*setmap.keys())
+            if len(platforms) == 0:
+                continue
         tree.insert(f, setmap)
 
     # Print a legend.

codebasin/tree.py

@@ -61,6 +61,15 @@ def _build_parser() -> argparse.ArgumentParser:
             "May be specified multiple times.",
             "If not specified, all platforms will be included.",
             is_long=True,
+        ),
+    )
+    parser.add_argument(
+        "--prune",
+        dest="prune",
+        action="store_true",
+        help=_help_string(
+            "Prune unused files from the tree.",
+            is_long=True,
             is_last=True,
         ),
     )
@@ -131,7 +140,7 @@ def _tree(args: argparse.Namespace):
     )
 
     # Print the file tree.
-    report.files(codebase, state)
+    report.files(codebase, state, prune=args.prune)
     sys.exit(0)