Enabled parent method calls via der obj and improved tests

Author: tanay-man

integration_tests/class_05.py

@@ -33,4 +33,5 @@ def main():
     assert op2 == "Whiskers is a 3-year-old Cat."
     print(cat.is_domestic)
     assert cat.is_domestic == True
+
 main()

integration_tests/class_06.py

@@ -1,24 +1,36 @@
 from lpython import i32
+
 class Base():
     def __init__(self:"Base"):
         self.x : i32 = 10
 
+    def get_x(self:"Base")->i32:
+        print(self.x)
+        return self.x
+    
+#Testing polymorphic fn calls    
+def get_x_static(d: Base)->i32:
+    print(d.x)
+    return d.x
+
 class Derived(Base):
     def __init__(self: "Derived"):
         super().__init__()
-        fn()
-        self.y : i32 = 20        
+        self.y : i32 = 20 
 
-def f(i:Base) -> i32:
-    print(i.x)
-    return i.x
+    def get_y(self:"Derived")->i32:
+        print(self.y)
+        return self.y       
 
-def fn():
-    print("Inside fn")
 
 def main():
     d : Derived = Derived()
-    op :i32 = f(d)
-    assert op == 10
+    x : i32 = get_x_static(d)
+    assert x == 10
+    # Testing parent method call using der obj
+    x = d.get_x()
+    assert x == 10
+    y: i32 = d.get_y()
+    assert y == 20
 
 main()

src/lpython/semantics/python_ast_to_asr.cpp

@@ -8146,7 +8146,8 @@ we will have to use something else.
                         //TODO: Correct Class and ClassType
                         // call to struct member function
                         // modifying args to pass the object as self
-                        ASR::symbol_t* der = ASR::down_cast<ASR::StructType_t>(var->m_type)->m_derived_type;
+                        ASR::symbol_t* der_sym = ASR::down_cast<ASR::StructType_t>(var->m_type)->m_derived_type;
+                        ASR::Struct_t* der = ASR::down_cast<ASR::Struct_t>(der_sym);
                         Vec<ASR::call_arg_t> new_args; new_args.reserve(al, args.n + 1);
                         ASR::call_arg_t self_arg;
                         self_arg.loc = args[0].loc;
@@ -8155,7 +8156,19 @@ we will have to use something else.
                         for (size_t i=0; i<args.n; i++) {
                             new_args.push_back(al, args[i]);
                         }
-                        st = get_struct_member(der, call_name, loc);
+                        if ( der->m_symtab->get_symbol(call_name) ) {
+                            st = get_struct_member(der_sym, call_name, loc);
+                        } else if ( der->m_parent ) {
+                            ASR::Struct_t* parent = ASR::down_cast<ASR::Struct_t>(der->m_parent);
+                            if ( !parent->m_symtab->get_symbol(call_name) ) {
+                                throw SemanticError("Method not found in the class or parents",loc);
+                            } else {
+                                st = get_struct_member(der->m_parent, call_name, loc);
+                            }
+                        } else {
+                            throw SemanticError("Method not found in the class "+std::string(der->m_name)+
+                                " or it's parents",loc);    
+                        }
                         tmp = make_call_helper(al, st, current_scope, new_args, call_name, loc);
                         return;
                     } else {

tests/reference/asr-structs_09-f3ffe08.json

@@ -8,6 +8,6 @@
     "stdout": null,
     "stdout_hash": null,
     "stderr": "asr-structs_09-f3ffe08.stderr",
-    "stderr_hash": "f59ab2d213f6423e0a891e43d5a19e83d4405391b1c7bf481b4b939e",
+    "stderr_hash": "14119a0bc6420ad242b99395d457f2092014d96d2a1ac81d376c649d",
     "returncode": 2
 }

tests/reference/asr-structs_09-f3ffe08.stderr

@@ -1,4 +1,4 @@
-semantic error: read not present in StringIO dataclass
+semantic error: Method not found in the class StringIO or it's parents
   --> tests/errors/structs_09.py:13:23
    |
 13 |     bytes_read: i32 = fd.read()