More on Builtin.contribute and Builtin.get_functions.

mathics/core/builtin.py

@@ -239,12 +239,16 @@ def __init__(self, *args, **kwargs):
     def contribute(self, definitions: Definitions, is_pymodule=False):
         from mathics.core.parser import parse_builtin_rule
 
-        # Set the default context
-        if not self.context:
-            self.context = "Pymathics`" if is_pymodule else "System`"
         name = self.get_name()
         attributes = self.attributes
         options = {}
+        # Set the default context
+        if not self.context:
+            self.context = "Pymathics`" if is_pymodule else "System`"
+            # get_name takes the context from the class, not from the
+            # instance, so even if we set the context here,
+            # self.get_name() does not includes the context.
+            name = self.context + name
 
         # - 'Strict': warn and fail with unsupported options
         # - 'Warn': warn about unsupported options, but continue
@@ -468,7 +472,15 @@ def get_functions(self, prefix="eval", is_pymodule=False):
                 if pattern is None:  # Fixes PyPy bug
                     continue
                 else:
-                    m = re.match(r"[(]([\w,]+),[)]\:\s*(.*)", pattern)
+                    # TODO: consider to use a more sophisticated
+                    # regular expression, which handles breaklines
+                    # more properly, that supports format names
+                    # with contexts (context`name) and be less
+                    # fragile against leaving spaces between the
+                    # elements.
+                    m = re.match(
+                        r"[(]([\w,]+),[ ]*[)]\:\s*(.*)", pattern.replace("\n", " ")
+                    )
                 if m is not None:
                     attrs = m.group(1).split(",")
                     pattern = m.group(2)

test/core/test_builtin.py

@@ -0,0 +1,63 @@
+"""
+Test how builtins are loaded
+"""
+
+from mathics.builtin.makeboxes import MakeBoxes
+from mathics.core.builtin import Builtin
+from mathics.core.definitions import Definitions
+
+
+def test_contribute_builtin():
+    """Test for Builtin.contribute."""
+
+    definitions = Definitions()
+    MakeBoxes.context = "System`"
+    MakeBoxes(expression=False).contribute(definitions)
+
+    class TestBuiltin(Builtin):
+        """
+        <dl>
+          <dt>'TestBuiltin'[$x$]
+          <dd>nothing
+        </dl>
+        """
+
+        messages = {
+            "nomsg": "Test message `1`.",
+        }
+
+        def eval_downvalue(self, expr, evaluation):
+            """expr: TestBuiltin[_:Symbol]"""
+            return
+
+        def eval_upvalue(self, expr, x, evaluation):
+            """expr: G[TestBuiltin[x_:Symbol]]"""
+            return
+
+        def format_parm1(self, expr, x, evaluation):
+            """(CustomForm,): expr: F[x_:Symbol]"""
+            return
+
+        def format_parm2(self, expr, x, y, evaluation):
+            """(MakeBoxes, ):expr: G[x_:Symbol,
+            y_]
+            """
+            return
+
+        def format_parmb(self, expr, x, y, evaluation):
+            """(OutputForm,): expr: G[x_:Symbol,
+            y:P|Q]
+            """
+            return
+
+    TestBuiltin(expression=False).contribute(definitions)
+    assert "System`TestBuiltin" in definitions.builtin.keys()
+    definition = definitions.get_definition("System`TestBuiltin")
+    # Check that the formats are loaded into the right places.
+    assert "System`MakeBoxes" in definition.formatvalues
+    assert "System`CustomForm" in definition.formatvalues
+    assert "System`OutputForm" in definition.formatvalues
+    # Test if the rules are loaded into the right place.
+    assert definition.upvalues
+    assert definition.downvalues
+    assert definition.messages