Add C support for a class containing only scalar data (#1472)

- Visit the lhs of a `DottedVariable`.
- Add `is_argument = True` for the `self` variable when it's in a method
argument of a class.
- Add the declaration of the attributes of the class in the `struct def`.

---------

Co-authored-by: EmilyBourne <louise.bourne@gmail.com>

CHANGELOG.md

@@ -5,6 +5,8 @@ All notable changes to this project will be documented in this file.
 
 ### Added
 
+-   #1472 : Add C printing support for a class containing scalar data.
+
 ### Fixed
 
 -   #1484 : Use scope for classes to avoid name clashes.

pyccel/codegen/printing/ccode.py

@@ -14,7 +14,7 @@
 from pyccel.ast.builtins  import PythonList, PythonTuple
 
 from pyccel.ast.core      import Declare, For, CodeBlock
-from pyccel.ast.core      import FuncAddressDeclare, FunctionCall, FunctionCallArgument, FunctionDef
+from pyccel.ast.core      import FuncAddressDeclare, FunctionCall, FunctionCallArgument, ClassDef
 from pyccel.ast.core      import Allocate, Deallocate
 from pyccel.ast.core      import FunctionAddress, FunctionDefArgument
 from pyccel.ast.core      import Assign, Import, AugAssign, AliasAssign
@@ -736,6 +736,7 @@ def _print_ModuleHeader(self, expr):
         funcs = ""
         for classDef in expr.module.classes:
             classes += f"struct {classDef.name} {{\n"
+            classes += ''.join(self._print(Declare(var.dtype,var)) for var in classDef.attributes)
             for method in classDef.methods:
                 method.rename(classDef.name + ("__" + method.name if not method.name.startswith("__") else method.name))
                 funcs += f"{self.function_signature(method)};\n"

pyccel/parser/semantic.py

@@ -1267,7 +1267,7 @@ def _assign_lhs_variable(self, lhs, d_var, rhs, new_expressions, is_augassign,ar
                 # the following is a small fix, since lhs must be already
                 # declared
                 if isinstance(lhs, DottedName):
-                    lhs = var.clone(var.name, new_class = DottedVariable, lhs = lhs.name[0])
+                    lhs = var.clone(var.name, new_class = DottedVariable, lhs = self._visit(lhs.name[0]))
                 else:
                     lhs = var
         else:
@@ -3281,7 +3281,7 @@ def _visit_FunctionDef(self, expr):
                 dt        = self.get_class_construct(cls_name)()
                 cls_base  = self.scope.find(cls_name, 'classes')
                 cls_base.scope.insert_symbols(expr.scope.local_used_symbols.copy())
-                var       = Variable(dt, 'self', cls_base=cls_base)
+                var       = Variable(dt, 'self', cls_base=cls_base, is_argument=True)
                 self.scope.insert_variable(var)
 
             if arguments:

tests/pyccel/scripts/classes/classes_3.py

@@ -0,0 +1,24 @@
+# pylint: disable=missing-class-docstring, missing-function-docstring, missing-module-docstring
+# coding: utf-8
+
+#$ header class Point1(public)
+#$ header method __init__(Point1, double)
+#$ header class Point2(public)
+#$ header method __init__(Point2, double)
+#$ header method test_func(Point2)
+
+class Point1:
+    def __init__(self, x):
+        self.x = x
+
+class Point2:
+    def __init__(self, y):
+        self.y = y
+
+    def test_func(self):
+        p = Point1(self.y)
+        print(p.x)
+
+if __name__ == '__main__':
+    j = Point2(2.2)
+    j.test_func()

tests/pyccel/test_pyccel.py

@@ -863,9 +863,8 @@ def test_basic_header():
 
 #------------------------------------------------------------------------------
 @pytest.mark.parametrize( "test_file", ["scripts/classes/classes.py",
-                                        "scripts/classes/classes_1.py",
-                                        "scripts/classes/classes_5.py",
                                         "scripts/classes/generic_methods.py",
+                                        "scripts/classes/classes_1.py",
                                         ] )
 @pytest.mark.parametrize( 'language', (
         pytest.param("python", marks = pytest.mark.python),
@@ -882,6 +881,8 @@ def test_classes_f_only( test_file , language):
 #------------------------------------------------------------------------------
 @pytest.mark.xdist_incompatible
 @pytest.mark.parametrize( "test_file", ["scripts/classes/classes_2_C.py",
+                                        "scripts/classes/classes_5.py",
+                                        "scripts/classes/classes_3.py",
                                         ] )
 @pytest.mark.parametrize( 'language', (
         pytest.param("python", marks = pytest.mark.python),