Detect Pine shadowing and ATR-based consistency

Author: Poryaei

src/pinescript_validator/ast_validator.py

@@ -22,6 +22,8 @@
     }
 )
 
+CONSISTENCY_PROPAGATION_BUILTINS = CONSISTENCY_SENSITIVE_BUILTINS | frozenset({"ta.atr"})
+
 PLOT_COUNT_LIMIT = 64
 
 
@@ -154,6 +156,17 @@ def define_symbol(
     ) -> None:
         if name == "_":
             return
+        if kind in {"variable", "parameter", "iterator"} and name in self.builtins.standalone_variables:
+            self.errors.append(
+                Diagnostic(
+                    line=line,
+                    column=column,
+                    length=len(name),
+                    message=f'Shadowing built-in variable "{name}"',
+                    severity=Severity.WARNING,
+                    source="ast",
+                )
+            )
         existing = scope.symbols.get(name)
         if existing is None:
             scope.symbols[name] = Symbol(name=name, line=line, column=column, kind=kind, type_name=type_name)
@@ -586,9 +599,15 @@ def expression_uses_consistency_sensitive_state(self, expression: AST.Expression
         if isinstance(expression, AST.CallExpression):
             function_name = self.extract_function_name(expression.callee)
             resolved_function_name = self.resolve_generic_function_name(function_name) if function_name is not None else None
-            if function_name in self.consistency_sensitive_functions:
+            if function_name in self.consistency_sensitive_functions or function_name in CONSISTENCY_PROPAGATION_BUILTINS:
                 return True
-            if resolved_function_name is not None and resolved_function_name in self.consistency_sensitive_functions:
+            if (
+                resolved_function_name is not None
+                and (
+                    resolved_function_name in self.consistency_sensitive_functions
+                    or resolved_function_name in CONSISTENCY_PROPAGATION_BUILTINS
+                )
+            ):
                 return True
             if self.expression_uses_consistency_sensitive_state(expression.callee):
                 return True

tests/test_validator.py

@@ -50,6 +50,10 @@ def test_unused_variable(self) -> None:
         diagnostics = self.validator.validate_text('indicator("Test")\nvalue = close')
         self.assertTrue(any("never used" in diagnostic.message for diagnostic in diagnostics))
 
+    def test_shadowing_builtin_variable_is_reported(self) -> None:
+        diagnostics = self.validator.validate_text("foo(int bar_index) =>\n    bar_index")
+        self.assertTrue(any('Shadowing built-in variable "bar_index"' in diagnostic.message for diagnostic in diagnostics))
+
     def test_untyped_variable_declaration_cannot_use_na(self) -> None:
         diagnostics = self.validator.validate_text("x = na")
         self.assertTrue(
@@ -348,6 +352,20 @@ def test_consistency_warning_for_user_function_wrapping_ema_and_stdev(self) -> N
         self.assertTrue(any('The function "f_zscore" should be called on each calculation for consistency.' in d.message for d in diagnostics))
         self.assertTrue(any("extract the call from the ternary operator or from the scope" in d.message for d in diagnostics))
 
+    def test_consistency_warning_for_user_function_wrapping_atr(self) -> None:
+        code = """
+f_push_struct_label_draw(y) =>
+    atrv = ta.atr(14)
+    y + atrv
+
+if cond
+    value = f_push_struct_label_draw(close)
+"""
+        diagnostics = self.validator.validate_text(code)
+        self.assertTrue(any('The function "f_push_struct_label_draw" should be called on each calculation for consistency.' in d.message for d in diagnostics))
+        self.assertTrue(any("extract the call from this scope" in d.message for d in diagnostics))
+        self.assertFalse(any('The function "ta.atr" should be called on each calculation for consistency.' in d.message for d in diagnostics))
+
     def test_consistency_warning_for_conditional_cross_functions_and_sensitive_wrapper(self) -> None:
         code = """
 f_detect_breakout_direction(level_up, level_down) =>