fix(declare): refuse a part reference that closes a master-part group cycle

src/datajoint/autopopulate.py

@@ -189,7 +189,12 @@ def __get__(self, obj, objtype=None):
 
     jobs: Job = _JobsDescriptor()
 
-    def _declare_check(self, primary_key: list[str], fk_attribute_map: dict[str, tuple[str, str]]) -> None:
+    def _declare_check(
+        self,
+        primary_key: list[str],
+        fk_attribute_map: dict[str, tuple[str, str]],
+        foreign_keys: list[tuple[str, dict[str, str]]],
+    ) -> None:
         """
         Validate FK-only primary key constraint for auto-populated tables.
 
@@ -203,6 +208,9 @@ def _declare_check(self, primary_key: list[str], fk_attribute_map: dict[str, tup
             List of primary key attribute names.
         fk_attribute_map : dict
             Mapping of child_attr -> (parent_table, parent_attr).
+        foreign_keys : list
+            One ``(parent_table, attr_map)`` entry per foreign key.
+            Not used here.
 
         Raises
         ------

src/datajoint/declare.py

@@ -204,6 +204,7 @@ def compile_foreign_key(
     fk_attribute_map: dict[str, tuple[str, str]] | None = None,
     fk_index_candidates: list[list[str]] | None = None,
     column_comments: dict[str, str] | None = None,
+    foreign_keys: list[tuple[str, dict[str, str]]] | None = None,
 ) -> None:
     """
     Parse a foreign key line and update declaration components.
@@ -239,6 +240,11 @@ def compile_foreign_key(
         out of line (PostgreSQL's ``COMMENT ON COLUMN``). Each copied column's
         comment, with its core-type marker (e.g. ``:int32:``), is added so the
         child keeps the parent's declared type. Updated in place.
+    foreign_keys : list, optional
+        One ``(parent_table, attr_map)`` entry per foreign key, where
+        ``attr_map`` maps each child attribute to the parent attribute it
+        references. Unlike ``fk_attribute_map``, it keeps every reference when
+        several share an attribute. Updated in place.
 
     Raises
     ------
@@ -327,6 +333,9 @@ def compile_foreign_key(
     foreign_key_sql.append(
         f"FOREIGN KEY ({fk_cols}) REFERENCES {ref_table_name} ({pk_cols}) ON UPDATE CASCADE ON DELETE RESTRICT"
     )
+    if foreign_keys is not None:
+        attr_map = {attr: ref.heading[attr].original_name for attr in ref.primary_key}
+        foreign_keys.append((ref_table_name, attr_map))
 
     # Supporting index on the foreign-key columns.
     #
@@ -382,7 +391,13 @@ def _tier_attributes(table_name: str | None, config) -> tuple[str, ...]:
 
 
 def prepare_declare(
-    definition: str, context: dict, adapter, *, table_name: str | None = None, config=None
+    definition: str,
+    context: dict,
+    adapter,
+    *,
+    table_name: str | None = None,
+    config=None,
+    foreign_keys: list[tuple[str, dict[str, str]]] | None = None,
 ) -> tuple[str, list[str], list[str], list[str], list[str], list[str], dict[str, tuple[str, str]], dict[str, str]]:
     """
     Parse a table definition into its components.
@@ -407,6 +422,9 @@ def prepare_declare(
         declares them.
     config : Config, optional
         Read for ``jobs.add_job_metadata`` and ``provenance.capture``.
+    foreign_keys : list, optional
+        Receives one ``(parent_table, attr_map)`` entry per foreign
+        key; see :func:`compile_foreign_key`. Updated in place.
 
     Returns
     -------
@@ -469,6 +487,7 @@ def add_attribute(line: str, in_key: bool) -> None:
                 fk_attribute_map,
                 fk_index_candidates,
                 column_comments,
+                foreign_keys,
             )
         elif re.match(r"^(unique\s+)?index\s*\(.*\)\s*(#.*)?$", line, re.I):  # index
             compile_index(re.sub(r"\s*#.*$", "", line), index_sql, adapter)
@@ -534,7 +553,13 @@ def _covered(candidate: list[str]) -> bool:
 
 
 def declare(
-    full_table_name: str, definition: str, context: dict, adapter, *, config=None
+    full_table_name: str,
+    definition: str,
+    context: dict,
+    adapter,
+    *,
+    config=None,
+    foreign_keys: list[tuple[str, dict[str, str]]] | None = None,
 ) -> tuple[str, list[str], list[str], dict[str, tuple[str, str]], list[str], list[str]]:
     r"""
     Parse a definition and generate SQL CREATE TABLE statement.
@@ -551,6 +576,9 @@ def declare(
         Database adapter for backend-specific SQL generation.
     config : Config, optional
         Configuration object. If None, falls back to global config.
+    foreign_keys : list, optional
+        Receives one ``(parent_table, attr_map)`` entry per foreign
+        key; see :func:`compile_foreign_key`. Updated in place.
 
     Returns
     -------
@@ -593,7 +621,7 @@ def declare(
         external_stores,
         fk_attribute_map,
         column_comments,
-    ) = prepare_declare(definition, context, adapter, table_name=table_name, config=config)
+    ) = prepare_declare(definition, context, adapter, table_name=table_name, config=config, foreign_keys=foreign_keys)
 
     pre_ddl = []  # DDL to run BEFORE CREATE TABLE (e.g., CREATE TYPE for enums)
     post_ddl = []  # DDL to run AFTER CREATE TABLE (e.g., COMMENT ON)