parser honours defaults by default

Author: telmomenezes

src/hyperbase/parsers/__init__.py

@@ -31,6 +31,14 @@ def get_parser(
     compatibility, keyword arguments are merged into *params* (explicit
     *params* entries take precedence).
 
+    Any parameter the caller does not supply is seeded with the
+    ``"default"`` declared in the parser's :meth:`Parser.accepted_params`,
+    so a programmatic caller gets the same effective configuration as the
+    REPL/CLI front-ends (which pre-fill those defaults before constructing
+    the parser). A declared default of ``None`` means "no default" — it is
+    left unset so the parser's own ``__init__`` fallback or validation
+    applies.
+
     Raises :class:`ValueError` if the parser is not installed.
     """
     parsers = list_parsers()
@@ -41,6 +49,9 @@ def get_parser(
         )
     merged: dict[str, Any] = {**kwargs, **(params or {})}
     cls = parsers[name].load()
+    for pname, info in cls.accepted_params().items():
+        if pname not in merged and info.get("default") is not None:
+            merged[pname] = info["default"]
     return cls(merged)
 
 

tests/test_parser_plugin.py

@@ -82,7 +82,15 @@ def parse_sentence(self, sentence):
 
         parser = get_parser("mock", params={"lang": "en"})
         assert isinstance(parser, MockParser)
-        assert parser.params == {"lang": "en"}
+        # get_parser seeds any unset accepted_params() default (here the base
+        # class's max_depth) so programmatic callers match the REPL/CLI, while
+        # preserving the caller's own values.
+        default_depth = MockParser.accepted_params()["max_depth"]["default"]
+        assert parser.params == {"lang": "en", "max_depth": default_depth}
+
+        # A caller-supplied value wins over the seeded schema default.
+        overridden = get_parser("mock", params={"max_depth": 7})
+        assert overridden.params["max_depth"] == 7
 
     @patch("hyperbase.parsers.entry_points")
     def test_plugin_load_failure(self, mock_eps):