persist: add attributes props to accumulator

pkgs/clan-cli/clan_lib/persist/write_rules.py

@@ -8,7 +8,9 @@ WRITABLE_PRIORITY_THRESHOLD = 100  # Values below this are not writeable
 
 
 class PersistenceAttribute(Enum):
+    WRITE = "write"
     READONLY = "readonly"
+    DELETE = "delete"  # can be deleted
 
 
 class AttributeMap(TypedDict):
@@ -112,6 +114,8 @@ def _determine_writeability_recursive(
     """Recursively determine writeability for all paths in the priority structure.
 
     This is internal recursive function. Use 'determine_writeability' as entry point.
+
+    results: AttributeMap that accumulates results, returned at the end.
     """
     if results is None:
         results = AttributeMap(writeable=set(), non_writeable=set(), attrs={})
@@ -121,8 +125,28 @@ def _determine_writeability_recursive(
         if key in {"__this", "__list", "__prio"}:
             continue
 
+        def get_inventory_exclusive(value: dict) -> bool | None:
+            if "__this" not in value or value:
+                return None
+
+            definition_locations = value.get("__this", {}).get("files")
+            if not definition_locations:
+                return None
+
+            return (
+                len(definition_locations) == 1
+                and definition_locations[0] == "inventory.json"
+            )
+
         path = (*current_path, key)
 
+        # If the value is defined only in inventory.json, we might be able to delete it.
+        # If we don't know (None), decide to allow deletion as well. (Backwards compatibility)
+        # Unless there is a default that applies instead, when removed. Currently we cannot test that.
+        # So we assume exclusive values can be removed. In reality we might need to check defaults too. (TODO)
+        is_inventory_exclusive = get_inventory_exclusive(value)
+        if is_inventory_exclusive or is_inventory_exclusive is None:
+            results["attrs"].setdefault(path, set()).add(PersistenceAttribute.DELETE)
         # Determine priority for this key
         key_priority = get_priority(value)
         effective_priority = (
@@ -135,6 +159,8 @@ def _determine_writeability_recursive(
         )
 
         if force_non_writeable:
+            results["attrs"].setdefault(path, set()).add(PersistenceAttribute.READONLY)
+            # Legacy:
             results["non_writeable"].add(path)
             # All children are also non-writeable
             if isinstance(value, dict):
@@ -157,8 +183,13 @@ def _determine_writeability_recursive(
             value_in_all = all_values.get(key)
 
             if is_key_writeable(effective_priority, exists_in_persisted, value_in_all):
+                # TODO: Distinguish between different write types?
+                results["attrs"].setdefault(path, set()).add(PersistenceAttribute.WRITE)
+                # Legacy:
                 results["writeable"].add(path)
             else:
+                results["attrs"].setdefault(path, set()).add(PersistenceAttribute.READONLY)
+                # Legacy:
                 results["non_writeable"].add(path)
 
             # Recurse into children

pkgs/clan-cli/clan_lib/persist/write_rules_test.py

@@ -50,10 +50,8 @@ def test_write_simple() -> None:
     data: dict = {}
     res = compute_write_map(prios, default, data)
 
-    assert res == {
-        "writeable": {("foo", "bar"), ("foo",), ("foo.bar",)},
-        "non_writeable": set(),
-    }
+    assert res["writeable"] == {("foo", "bar"), ("foo",), ("foo.bar",)}
+    assert res["non_writeable"] == set()
 
 
 # Compatibility test for old __prio style
@@ -73,10 +71,8 @@ def test_write_inherited() -> None:
     data: dict = {}
     res = compute_write_map(prios, {"foo": {"bar": {}}}, data)
 
-    assert res == {
-        "writeable": {("foo",), ("foo", "bar"), ("foo", "bar", "baz")},
-        "non_writeable": set(),
-    }
+    assert res["writeable"] == {("foo", "bar"), ("foo",), ("foo", "bar", "baz")}
+    assert res["non_writeable"] == set()
 
 
 def test_non_write_inherited() -> None:
@@ -93,10 +89,8 @@ def test_non_write_inherited() -> None:
     data: dict = {}
     res = compute_write_map(prios, {}, data)
 
-    assert res == {
-        "writeable": set(),
-        "non_writeable": {("foo",), ("foo", "bar", "baz"), ("foo", "bar")},
-    }
+    assert res["non_writeable"] == {("foo",), ("foo", "bar"), ("foo", "bar", "baz")}
+    assert res["writeable"] == set()
 
 
 def test_write_list() -> None:
@@ -114,10 +108,9 @@ def test_write_list() -> None:
         ],  # <- writeable: because lists are merged. Filtering out nix-values comes later
     }
     res = compute_write_map(prios, default, data)
-    assert res == {
-        "writeable": {("foo",)},
-        "non_writeable": set(),
-    }
+
+    assert res["writeable"] == {("foo",)}
+    assert res["non_writeable"] == set()
 
 
 def test_write_because_written() -> None:
@@ -138,10 +131,9 @@ def test_write_because_written() -> None:
     # Given the following data. {}
     # Check that the non-writeable paths are correct.
     res = compute_write_map(prios, {"foo": {"bar": {}}}, {})
-    assert res == {
-        "writeable": {("foo",), ("foo", "bar")},
-        "non_writeable": {("foo", "bar", "baz"), ("foo", "bar", "foobar")},
-    }
+
+    assert res["writeable"] == {("foo",), ("foo", "bar")}
+    assert res["non_writeable"] == {("foo", "bar", "baz"), ("foo", "bar", "foobar")}
 
     data: dict = {
         "foo": {
@@ -151,7 +143,4 @@ def test_write_because_written() -> None:
         },
     }
     res = compute_write_map(prios, {}, data)
-    assert res == {
-        "writeable": {("foo",), ("foo", "bar"), ("foo", "bar", "baz")},
-        "non_writeable": {("foo", "bar", "foobar")},
     }