test: cover compatibility function multiplication returns

docs/CURRENT_STATUS.md

@@ -64,7 +64,7 @@ Ready now:
 - typed `TEACH ... RETURNS` declarations reject a missing return type with a direct repair hint, such as `Function greet needs a return type after RETURNS. Add a type such as NUMBER.` The same diagnostic names the complete class and method, including compatibility `TAKES` / `LEARNED` methods: `Method Player.score needs a return type after RETURNS. Add a type such as NUMBER.`
 - typed list/map checks through `claro typecheck`, including a nested `LIST OF MAP` insertion example
 - simple function and object-method return checks with `TEACH name ... RETURNS TYPE`, including learner-facing diagnostics for unknown declared return types, mismatched or not-yet-inferable `RETURN` expressions (including method-specific diagnostics naming the class and method, with modern and compatibility method coverage), empty `RETURN` statements in modern and compatibility functions and methods, declarations that contain no `RETURN`, and declarations whose only return is inside an incomplete conditional; missing return types are checked for modern functions and both modern and compatibility methods, with compatibility-function coverage as well; extra text after a return value is rejected consistently in modern functions, compatibility `TAKES` / `LEARNED` functions, and both method forms; `RETURNS` is case-insensitive like other Claro keywords and has positive coverage in both modern and compatibility function forms, including lowercase compatibility declarations and lowercase compatibility method declarations, plus a lowercase compatibility-method mismatch diagnostic; positive function-return coverage includes numeric multiplication; compatibility methods now have dedicated positive numeric addition, subtraction, division, and multiplication return fixtures plus compatibility addition, subtraction, division, and multiplication diagnostic fixtures; NUMBER return diagnostics name a known TEXT operand and arithmetic operation instead of hiding the cause behind a generic mismatch, with focused addition, subtraction, multiplication, and division coverage for functions and methods; typed-function return diagnostics now have focused subtraction and division positives alongside multiplication coverage. Text concatenation into a TEXT field has focused positive fixtures for both operand orders, including concatenation of two TEXT object fields. Each numeric operator names the text operand and explains that it needs NUMBER values.
-- compatibility `TAKES` / `LEARNED` functions also have focused positive numeric-addition, subtraction, and division return fixtures, keeping arithmetic return coverage aligned with modern functions and compatibility methods.
+- compatibility `TAKES` / `LEARNED` functions also have focused positive numeric-addition, subtraction, division, and multiplication return fixtures, keeping arithmetic return coverage aligned with modern functions and compatibility methods.
 - a narrow function/method argument check: `CHECK TYPE parameter IS TYPE` inside a function or simple object method lets `claro typecheck` accept correct checked calls, catch mismatched `DO`, `CALL ... WITH`, `DO object.method ...`, and compatibility `CALL object.method WITH ...` arguments, including checked methods that appear after another method in the same class, report missing checked function and method arguments, report missing unchecked arguments for simple functions and simple object methods in both modern `DO` and compatibility `CALL ... WITH` forms, treat empty compatibility calls such as `CALL greet WITH` and `CALL player.rename WITH` as missing-argument mistakes, catch extra arguments to simple functions and checked methods even when the checked method appears after another method in the same class, catch modern `DO` and compatibility `CALL ... WITH` calls to undeclared simple functions, explain when `DO object.method ...` or compatibility `CALL object.method ...` happens before the object is created with `NEW` even if the method name is also wrong, and catch modern plus compatibility calls to undeclared object methods with a class-specific `TEACH` hint
 - function and method declarations now reject repeated parameter names with a direct repair hint before calls are checked, including modern and compatibility `TAKES` / `LEARNED` functions and methods; object methods with the same name are also rejected within a class with a rename hint in both modern and compatibility method syntax
 - top-level function declarations now reject repeated names with a direct repair hint, so two `TEACH greet` blocks cannot silently compete for one callable function; a missing function name after `TEACH` gets a direct beginner-facing repair hint, and a missing method name inside `CLASS` names the class and gives a method example

docs/ROADMAP.md

@@ -36,7 +36,7 @@ See `CURRENT_STATUS.md` for the detailed feature matrix.
 3b. Keep package security validation in Forgejo/Gitea CI so unsafe names, exact manifest-version/name/version/checksum mismatches, missing manifests, duplicate project manifest versions and packages, duplicate lock packages, duplicate package manifest names, versions, and checksums, and lockfile errors remain release blockers.
 4. Add small examples for each foundation feature before adding bigger syntax. The object-field foundation now includes positive and negative validation for field expressions such as `SET player.score player.name`, `SET player.score player.score + 1`, `SET player.name player.score + 1`, explicitly typed field assignments, explicit typed assignments to undeclared fields, simple and chained aliases such as `SET alias player`, `SET backup alias`, followed by `SET backup.score ...` or `CHECK TYPE backup.score IS ...`, chained aliases in object-method calls through both modern `DO` and compatibility `CALL ... WITH` forms (including a dedicated positive modern `DO` fixture), and arithmetic/text expression mismatches; typed containers also accept a map with nested type metadata when it is added to a `LIST OF MAP`; broader alias/control-flow checking remains planned.
 5. Keep the focused typecheck validator complete: the method-body field diagnostic fixtures are now exercised by `claro validate` alongside the standalone diagnostic validator; continue wiring each new `typecheck_*.claro` fixture into both gates. Modern and compatibility unknown-field expression diagnostics now have matching focused coverage, and explicitly typed unknown method-field assignments have matching modern and compatibility fixtures with the expected `HAS field TYPE` repair hint.
--6. Continue narrowing expression diagnostics: known TEXT operands now remain visible through arithmetic, with focused numeric-subtraction, numeric-division, and numeric-multiplication positives plus text-operand addition, subtraction, multiplication, and division coverage. Typed function returns now include positive subtraction and division examples alongside multiplication, including compatibility `TAKES` / `LEARNED` numeric-addition, subtraction, and division return fixtures. Text concatenation into TEXT fields is covered in both operand orders, including field-to-field concatenation. Each numeric operator names the text operand and explains that it needs NUMBER values. Compatibility method return diagnostics now cover addition, subtraction, division, and multiplication. `CHECK TYPE` also rejects misspelled expected type names.
+-6. Continue narrowing expression diagnostics: known TEXT operands now remain visible through arithmetic, with focused numeric-subtraction, numeric-division, and numeric-multiplication positives plus text-operand addition, subtraction, multiplication, and division coverage. Typed function returns now include positive subtraction and division examples alongside multiplication, including compatibility `TAKES` / `LEARNED` numeric-addition, subtraction, division, and multiplication return fixtures. Text concatenation into TEXT fields is covered in both operand orders, including field-to-field concatenation. Each numeric operator names the text operand and explains that it needs NUMBER values. Compatibility method return diagnostics now cover addition, subtraction, division, and multiplication. `CHECK TYPE` also rejects misspelled expected type names.
 - Keep typed method return examples balanced: numeric addition, subtraction, division, and multiplication now have dedicated positive compatibility `TAKES` / `LEARNED` method fixtures in the focused validator, alongside compatibility addition, subtraction, and division mismatch coverage and the existing method return mismatch diagnostics.
 - Keep method field examples balanced across syntax generations: modern and compatibility `TAKES` / `LEARNED` NUMBER, TEXT, and YESNO assignments now have positive fixtures beside the modern and compatibility mismatch fixtures, and modern plus compatibility YESNO method-field metadata now have dedicated positive fixtures beside the negative fixture.
 - Keep IDE metadata aligned with the current beginner syntax: typed-language keywords such as `RETURNS`, `CHECK`, and `TYPE` are now included in the metadata used by editor helpers.

tests/test_validate_typecheck_diagnostics.py

@@ -220,6 +220,12 @@ class ValidateTypecheckDiagnosticsTests(unittest.TestCase):
             MODULE.EXPECTED_OK,
         )
 
+    def test_includes_compatibility_function_multiplication_return_success_fixture(self):
+        self.assertIn(
+            "tests/typecheck_function_compat_return_multiplication_good.claro",
+            MODULE.EXPECTED_OK,
+        )
+
     def test_includes_lowercase_compatibility_method_return_success_fixture(self):
         self.assertIn(
             "tests/typecheck_method_compat_lowercase_return_good.claro",

tests/typecheck_function_compat_return_multiplication_good.claro

@@ -0,0 +1,6 @@
+TEACH total TAKES amount RETURNS NUMBER
+    CHECK TYPE amount IS NUMBER
+    RETURN amount * 2
+LEARNED
+
+CALL total WITH 4

tools/validate_typecheck_diagnostics.py

@@ -470,6 +470,7 @@ EXPECTED_OK = [
     "tests/typecheck_function_compat_return_addition_good.claro",
     "tests/typecheck_function_compat_return_subtraction_good.claro",
     "tests/typecheck_function_compat_return_division_good.claro",
+    "tests/typecheck_function_compat_return_multiplication_good.claro",
     "tests/typecheck_function_compat_lowercase_return_good.claro",
     "tests/typecheck_function_lowercase_return_good.claro",
     "tests/typecheck_function_return_expression_good.claro",