keep hierarchy option

tests/test_pack.py

@@ -694,6 +694,152 @@ class ProgressTest(AbstractPackTest):
         )
 
 
+class KeepHierarchyPackTest(AbstractPackTest):
+    def hierarchy_path(self, filepath) -> Path:
+        """Return the keep-hierarchy path for a file: target / strip_root(abs_path)."""
+        return Path(self.tpath, bpathlib.strip_root(filepath))
+
+    def test_strategise_keep_hierarchy_no_rewrite(self):
+        """When all deps are in-project with relative paths, no rewriting is needed."""
+        infile = self.blendfiles / "doubly_linked.blend"
+
+        packer = pack.Packer(
+            infile, self.blendfiles, self.tpath, keep_hierarchy=True
+        )
+        packer.strategise()
+
+        packed_files = (
+            "doubly_linked.blend",
+            "linked_cube.blend",
+            "basic_file.blend",
+            "material_textures.blend",
+            "textures/Bricks/brick_dotted_04-bump.jpg",
+            "textures/Bricks/brick_dotted_04-color.jpg",
+        )
+        for pf in packed_files:
+            path = self.blendfiles / pf
+            act = packer._actions[path]
+            self.assertEqual(
+                pack.PathAction.KEEP_PATH, act.path_action, "for %s" % pf
+            )
+            # In keep_hierarchy mode, paths use strip_root(abs_path) instead of
+            # relative_to(project).
+            self.assertEqual(
+                self.hierarchy_path(path), act.new_path, "for %s" % pf
+            )
+
+        self.assertEqual({}, self.rewrites(packer))
+        self.assertEqual(len(packed_files), len(packer._actions))
+
+    def test_strategise_keep_hierarchy_rewrite(self):
+        """Deps outside the project go to target/strip_root(path), not _outside_project/."""
+        ppath = self.blendfiles / "subdir"
+        infile = ppath / "doubly_linked_up.blend"
+
+        packer = pack.Packer(infile, ppath, self.tpath, keep_hierarchy=True)
+        packer.strategise()
+
+        # The blendfile itself should be at target / strip_root(abs_path)
+        act = packer._actions[infile]
+        self.assertEqual(pack.PathAction.KEEP_PATH, act.path_action)
+        self.assertEqual(self.hierarchy_path(infile), act.new_path)
+
+        # External files should NOT be under _outside_project/
+        external_files = (
+            "linked_cube.blend",
+            "basic_file.blend",
+            "material_textures.blend",
+            "textures/Bricks/brick_dotted_04-bump.jpg",
+            "textures/Bricks/brick_dotted_04-color.jpg",
+        )
+        for fn in external_files:
+            path = self.blendfiles / fn
+            act = packer._actions[path]
+            self.assertEqual(
+                pack.PathAction.FIND_NEW_LOCATION, act.path_action, "for %s" % fn
+            )
+            # Should be at target / strip_root(abs_path), NOT target/_outside_project/...
+            expected = self.hierarchy_path(path)
+            self.assertEqual(
+                expected,
+                act.new_path,
+                f"\nEXPECT: {expected}\nACTUAL: {act.new_path}\nfor {fn}",
+            )
+
+        # There should be no _outside_project in any new_path
+        for path, action in packer._actions.items():
+            self.assertNotIn(
+                "_outside_project",
+                str(action.new_path),
+                f"_outside_project should not appear in keep_hierarchy mode for {path}",
+            )
+
+    def test_execute_keep_hierarchy(self):
+        """Verify files are copied to correct hierarchy and paths are rewritten."""
+        ppath = self.blendfiles / "subdir"
+        infile = ppath / "doubly_linked_up.blend"
+
+        with pack.Packer(infile, ppath, self.tpath, keep_hierarchy=True) as packer:
+            packer.strategise()
+            packer.execute()
+
+        # The blendfile should be at its hierarchy position
+        packed_blend = self.hierarchy_path(infile)
+        self.assertTrue(packed_blend.exists(), "Blendfile should be in hierarchy")
+
+        # There should be NO _outside_project directory
+        self.assertFalse(
+            (self.tpath / "_outside_project").exists(),
+            "_outside_project should not exist in keep_hierarchy mode",
+        )
+
+        # Dependencies should be at their hierarchy positions
+        for fn in ("linked_cube.blend", "basic_file.blend", "material_textures.blend"):
+            dep_path = self.hierarchy_path(self.blendfiles / fn)
+            self.assertTrue(dep_path.exists(), "%s should be in hierarchy" % fn)
+
+        # Verify paths were rewritten correctly in the packed blend file.
+        # The rewritten paths should be relative from the packed blend to
+        # the packed dependencies.
+        bfile = blendfile.open_cached(packed_blend, assert_cached=False)
+        libs = sorted(bfile.code_index[b"LI"])
+
+        # Since keep_hierarchy preserves relative positions, the relative paths
+        # from subdir/doubly_linked_up.blend to the parent blendfiles should
+        # be the same as the originals (//../linked_cube.blend etc.)
+        self.assertEqual(b"LILib", libs[0].id_name)
+        self.assertEqual(b"//../linked_cube.blend", libs[0][b"name"])
+        self.assertEqual(b"LILib.002", libs[1].id_name)
+        self.assertEqual(b"//../material_textures.blend", libs[1][b"name"])
+
+    def test_execute_keep_hierarchy_no_touch_origs(self):
+        """Original files should not be modified."""
+        ppath = self.blendfiles / "subdir"
+        infile = ppath / "doubly_linked_up.blend"
+
+        with pack.Packer(infile, ppath, self.tpath, keep_hierarchy=True) as packer:
+            packer.strategise()
+            packer.execute()
+
+        # The original file shouldn't be touched.
+        bfile = blendfile.open_cached(infile, assert_cached=False)
+        libs = sorted(bfile.code_index[b"LI"])
+        self.assertEqual(b"LILib", libs[0].id_name)
+        self.assertEqual(b"//../linked_cube.blend", libs[0][b"name"])
+        self.assertEqual(b"LILib.002", libs[1].id_name)
+        self.assertEqual(b"//../material_textures.blend", libs[1][b"name"])
+
+    def test_keep_hierarchy_output_path(self):
+        """output_path should use the full hierarchy path."""
+        infile = self.blendfiles / "basic_file.blend"
+        packer = pack.Packer(
+            infile, self.blendfiles, self.tpath, keep_hierarchy=True
+        )
+        packer.strategise()
+
+        self.assertEqual(self.hierarchy_path(infile), packer.output_path)
+
+
 class AbortTest(AbstractPackTest):
     def test_abort_strategise(self):
         infile = self.blendfiles / "subdir/doubly_linked_up.blend"