Fix optional parameter unification

trans/stdlib/__init__.py

@@ -92,4 +92,13 @@ class file:
     def read(self) -> Task[str]: ...
     def close(self) -> Task[None]: ...
 
-def open(filename: str, mode: str) -> Task[file]: ...
\ No newline at end of file
+def open(filename: str, mode: str) -> Task[file]: ...
+
+def __test_opt(x: int, y: int = 5) -> int:
+    ...
+
+assert __test_opt
+assert __test_opt(5)
+assert __test_opt(5, 6)
+assert not __test_opt(5, 6, 7)
+assert not __test_opt()
\ No newline at end of file

trans/transpiler/phases/if_main/__init__.py

@@ -9,13 +9,8 @@ class IfMainVisitor(ast.NodeVisitor):
         for i, stmt in enumerate(node.body):
             if isinstance(stmt, ast.If):
                 if not stmt.orelse and compare_ast(stmt.test, NAME_MAIN):
-                    new_node = ast.FunctionDef(
-                        name="main",
-                        args=ast.arguments(args=[]),
-                        body=stmt.body,
-                        decorator_list=[],
-                        returns=None
-                    )
+                    new_node = ast.parse("def main(): pass").body[0]
+                    new_node.body = stmt.body
                     new_node.is_main = True
                     node.body[i] = new_node
                     return
\ No newline at end of file

trans/transpiler/phases/typing/block.py

@@ -55,7 +55,10 @@ class ScoperBlockVisitor(ScoperVisitor):
             raise NotImplementedError(node)
         target = node.targets[0]
         ty = self.get_type(node.value)
-        node.is_declare = self.visit_assign_target(target, ty)
+        try:
+            node.is_declare = self.visit_assign_target(target, ty)
+        except IncompatibleTypesError as e:
+            raise IncompatibleTypesError(f"`{ast.unparse(node)}: {e}")
 
     def visit_assign_target(self, target, decl_val: BaseType) -> bool:
         if isinstance(target, ast.Name):
@@ -92,6 +95,7 @@ class ScoperBlockVisitor(ScoperVisitor):
         scope.function = scope
         node.inner_scope = scope
         node.type = ftype
+        ftype.optional_at = 1 + len(node.args.args) - len(node.args.defaults)
         for arg, ty in zip(node.args.args, argtypes):
             scope.vars[arg.arg] = VarDecl(VarKind.LOCAL, ty)
         for b in node.body:

trans/transpiler/phases/typing/stdlib.py

@@ -77,6 +77,7 @@ class StdlibVisitor(NodeVisitorSeq):
         ty.typevars = arg_visitor.typevars
         if node.args.vararg:
             ty.variadic = True
+        ty.optional_at = 1 + len(node.args.args) - len(node.args.defaults)
         if self.cur_class:
             assert isinstance(self.cur_class, TypeType)
             if isinstance(self.cur_class.type_object, ABCMeta):
@@ -86,7 +87,16 @@ class StdlibVisitor(NodeVisitorSeq):
         self.scope.vars[node.name] = VarDecl(VarKind.LOCAL, ty)
 
     def visit_Assert(self, node: ast.Assert):
-        print("Type of", ast.unparse(node.test), ":=", self.expr().visit(node.test))
+        if isinstance(node.test, ast.UnaryOp) and isinstance(node.test.op, ast.Not):
+            oper = node.test.operand
+            try:
+                res = self.expr().visit(oper)
+            except:
+                print("Type of", ast.unparse(oper), ":=", "INVALID")
+            else:
+                raise AssertionError(f"Assertion should fail, got {res} for {ast.unparse(oper)}")
+        else:
+            print("Type of", ast.unparse(node.test), ":=", self.expr().visit(node.test))
 
     def visit_Call(self, node: ast.Call) -> BaseType:
         ty_op = self.visit(node.func)

trans/transpiler/phases/typing/types.py

@@ -144,6 +144,8 @@ class TypeOperator(BaseType, ABC):
     def unify_internal(self, other: BaseType):
         if not isinstance(other, TypeOperator):
             raise IncompatibleTypesError()
+        if len(self.args) < len(other.args):
+            return other.unify_internal(self)
         if type(self) != type(other):
             for parent in other.get_parents():
                 try:
@@ -161,28 +163,34 @@ class TypeOperator(BaseType, ABC):
                     return
             raise IncompatibleTypesError(f"Cannot unify {self} and {other} with different type and no common parents")
         if len(self.args) != len(other.args):
-            a, b = self, other
-            a_opt = a.optional_at is not None
-            b_opt = b.optional_at is not None
-            if a_opt and b_opt:
-                raise IncompatibleTypesError(f"This really should never happen")
-            if b_opt:
-                a, b = b, a
-            if a_opt:
-                # a = f(A, B; C=?, D=?)
-                # b = g(A, B, ... ?)
-                # either
-                # |a| < |b| => b has more args => invalid
-                # |a| ≥ |b| => b has less args => valid, up to |b|, so normal course of events
-
-                x = True
-
-                # c'est pété => utiliser le truc de la boucle en bas
-
-                # TODO: pas implémenté
-
             if not (self.variadic or other.variadic):
-                raise IncompatibleTypesError(f"Cannot unify {self} and {other} with different number of arguments")
+                pass
+                # # a, b = self, other
+                # # if a.optio
+                # # a_opt = a.optional_at is not None
+                # # b_opt = b.optional_at is not None
+                # # if a_opt and b_opt:
+                # #     raise IncompatibleTypesError(f"This really should never happen")
+                # # if b_opt:
+                # #     other.unify_internal(self)
+                # #     return
+                # if a_opt:
+                #     if len(a.args) < len(b.args):
+                #         raise IncompatibleTypesError(f"Cannot unify {self} and {other} with different number of arguments")
+                #     # a = f(A, B; C=?, D=?)
+                #     # b = g(A, B, ... ?)
+                #     # either
+                #     # |a| < |b| => b has more args => invalid
+                #     # |a| ≥ |b| => b has less args => valid, up to |b|, so normal course of events
+                #
+                #     x = True
+                #
+                #     # c'est pété => utiliser le truc de la boucle en bas
+                #
+                #     # TODO: pas implémenté
+                #
+                # # if not (self.variadic or other.variadic):
+                # #     raise IncompatibleTypesError(f"Cannot unify {self} and {other} with different number of arguments")
         if len(self.args) == 0:
             if self.name != other.name:
                 raise IncompatibleTypesError(f"Cannot unify {self} and {other}")
@@ -190,6 +198,12 @@ class TypeOperator(BaseType, ABC):
             if a is None and self.variadic or b is None and other.variadic:
                 continue
 
+            if a is not None and b is None:
+                if i >= self.optional_at:
+                    continue
+                else:
+                    raise IncompatibleTypesError(f"Cannot unify {self} and {other}, not enough arguments")
+
             if isinstance(a, BaseType) and isinstance(b, BaseType):
                 a.unify(b)
             else: