ifcquery/ifcedit: enable shell scripting by composing query and edit commands

Add --format ids to ifcquery to output step IDs suitable for piping into
ifcedit parameters. Add ifcedit foreach to apply an operation to every
element in a query result. Extend clash and relations output so --format ids
extracts all involved element IDs, enabling one-liners like clash detection
piped directly into render.

Generated with the assistance of an AI coding tool.

src/ifcquery/tests/test_main.py

@@ -82,3 +82,40 @@ class TestCLI:
     def test_no_command(self, ifc_path):
         rc, stdout, stderr = run_ifcquery(ifc_path)
         assert rc != 0
+
+    def test_select_ids_format(self, ifc_path):
+        rc, stdout, stderr = run_ifcquery(ifc_path, "--format", "ids", "select", "IfcWall")
+        assert rc == 0
+        # Should be a comma-separated string of integers with no surrounding whitespace
+        ids = stdout.strip()
+        assert ids != ""
+        for part in ids.split(","):
+            assert part.isdigit()
+
+    def test_select_ids_format_multiple(self, ifc_path, model):
+        rc, stdout, stderr = run_ifcquery(ifc_path, "--format", "ids", "select", "IfcElement")
+        assert rc == 0
+        ids = stdout.strip().split(",")
+        assert len(ids) >= 2
+
+    def test_ids_format_empty_result(self, ifc_path):
+        rc, stdout, stderr = run_ifcquery(ifc_path, "--format", "ids", "select", "IfcDoor")
+        assert rc == 0
+        assert stdout.strip() == ""
+
+    def test_relations_ids_format(self, ifc_path, model):
+        storey = model.by_type("IfcBuildingStorey")[0]
+        rc, stdout, stderr = run_ifcquery(ifc_path, "--format", "ids", "relations", str(storey.id()))
+        assert rc == 0
+        ids = stdout.strip().split(",")
+        assert all(i.isdigit() for i in ids)
+        # should include the storey itself and its contained elements
+        assert str(storey.id()) in ids
+        wall_id = str(model.by_type("IfcWall")[0].id())
+        assert wall_id in ids
+
+    def test_info_ids_format(self, ifc_path, model):
+        wall = model.by_type("IfcWall")[0]
+        rc, stdout, stderr = run_ifcquery(ifc_path, "--format", "ids", "info", str(wall.id()))
+        assert rc == 0
+        assert stdout.strip() == str(wall.id())

src/ifcquery/tests/test_relations.py

@@ -91,6 +91,47 @@ class TestTraverseUp:
         assert len(chain) == 4  # storey -> building -> site -> project
 
 
+class TestElementsSummary:
+    def test_wall_elements_includes_self(self, model):
+        wall = model.by_type("IfcWall")[0]
+        result = relations(model, wall)
+        ids = [e["id"] for e in result["elements"]]
+        assert wall.id() in ids
+
+    def test_wall_elements_includes_container(self, model):
+        wall = model.by_type("IfcWall")[0]
+        result = relations(model, wall)
+        ids = [e["id"] for e in result["elements"]]
+        storey = model.by_type("IfcBuildingStorey")[0]
+        assert storey.id() in ids
+
+    def test_storey_elements_includes_contained(self, model):
+        storey = model.by_type("IfcBuildingStorey")[0]
+        result = relations(model, storey)
+        ids = [e["id"] for e in result["elements"]]
+        wall = model.by_type("IfcWall")[0]
+        assert wall.id() in ids
+
+    def test_elements_no_duplicates(self, model):
+        storey = model.by_type("IfcBuildingStorey")[0]
+        result = relations(model, storey)
+        ids = [e["id"] for e in result["elements"]]
+        assert len(ids) == len(set(ids))
+
+    def test_elements_all_have_id_and_type(self, model):
+        wall = model.by_type("IfcWall")[0]
+        result = relations(model, wall)
+        for e in result["elements"]:
+            assert "id" in e
+            assert "type" in e
+
+    def test_traverse_up_has_no_elements_field(self, model):
+        wall = model.by_type("IfcWall")[0]
+        result = relations(model, wall, traverse="up")
+        assert isinstance(result, list)
+        assert not any("elements" in item for item in result)
+
+
 class TestJsonSerializable:
     def test_relations_serializable(self, model):
         wall = model.by_type("IfcWall")[0]