Fixed bug that leads to a false negative when passing multiple `*args…

packages/pyright-internal/src/analyzer/typeEvaluator.ts

@@ -11792,12 +11792,28 @@ export function createTypeEvaluator(
             if (paramSpec) {
                 if (argParam.argument.argCategory === ArgCategory.UnpackedList) {
                     if (isParamSpecArgs(paramSpec, argResult.argType)) {
+                        if (sawParamSpecArgs) {
+                            addDiagnostic(
+                                DiagnosticRule.reportCallIssue,
+                                LocMessage.paramSpecArgsKwargsDuplicate().format({ type: printType(paramSpec) }),
+                                argParam.errorNode
+                            );
+                        }
+
                         sawParamSpecArgs = true;
                     }
                 }
 
                 if (argParam.argument.argCategory === ArgCategory.UnpackedDictionary) {
                     if (isParamSpecKwargs(paramSpec, argResult.argType)) {
+                        if (sawParamSpecKwargs) {
+                            addDiagnostic(
+                                DiagnosticRule.reportCallIssue,
+                                LocMessage.paramSpecArgsKwargsDuplicate().format({ type: printType(paramSpec) }),
+                                argParam.errorNode
+                            );
+                        }
+
                         sawParamSpecKwargs = true;
                     }
                 }

packages/pyright-internal/src/localization/localize.ts

@@ -775,6 +775,8 @@ export namespace Localizer {
             new ParameterizedString<{ name: string }>(getRawString('Diagnostic.paramAnnotationMissing'));
         export const paramNameMissing = () =>
             new ParameterizedString<{ name: string }>(getRawString('Diagnostic.paramNameMissing'));
+        export const paramSpecArgsKwargsDuplicate = () =>
+            new ParameterizedString<{ type: string }>(getRawString('Diagnostic.paramSpecArgsKwargsDuplicate'));
         export const paramSpecArgsKwargsUsage = () => getRawString('Diagnostic.paramSpecArgsKwargsUsage');
         export const paramSpecArgsMissing = () =>
             new ParameterizedString<{ type: string }>(getRawString('Diagnostic.paramSpecArgsMissing'));

packages/pyright-internal/src/localization/package.nls.en-us.json

@@ -920,6 +920,10 @@
         "paramAnnotationMissing": "Type annotation is missing for parameter \"{name}\"",
         "paramAssignmentMismatch": "Expression of type \"{sourceType}\" cannot be assigned to parameter of type \"{paramType}\"",
         "paramNameMissing": "No parameter named \"{name}\"",
+        "paramSpecArgsKwargsDuplicate": {
+            "message": "Arguments for ParamSpec \"{type}\" have already been provided",
+            "comment": "{Locked='ParamSpec'}"
+        },
         "paramSpecArgsKwargsUsage": {
             "message": "\"args\" and \"kwargs\" attributes of ParamSpec must both appear within a function signature",
             "comment": "{Locked='args','kwargs','ParamSpec'}"

packages/pyright-internal/src/tests/samples/paramSpec49.py

@@ -57,3 +57,6 @@ def inner6(*args: P.args, **kwargs: P.kwargs) -> None:
             # extra *args argument.
             self.dispatcher.dispatch(stub, 1, *args, *args, **kwargs)
 
+            # This should generate an error because it has an
+            # extra **kwargs argument.
+            self.dispatcher.dispatch(stub, 1, *args, **kwargs, **kwargs)

packages/pyright-internal/src/tests/samples/paramSpec8.py

@@ -17,7 +17,7 @@ def func2(*args: P.args, s: str, t: int, **kwargs: P.kwargs) -> None:  # Rejecte
 
 
 def remove(f: Callable[Concatenate[int, P], int]) -> Callable[P, None]:
-    def foo(*args: P.args, **kwargs: P.kwargs) -> None:
+    def func1(*args: P.args, **kwargs: P.kwargs) -> None:
         f(1, *args, **kwargs)  # Accepted
 
         # Should generate an error because positional parameter
@@ -28,18 +28,24 @@ def foo(*args: P.args, **kwargs: P.kwargs) -> None:
         # is missing.
         f(*args, **kwargs)  # Rejected
 
-    return foo
+    return func1
 
 
 def outer(f: Callable[P, None]) -> Callable[P, None]:
-    def foo(x: int, *args: P.args, **kwargs: P.kwargs) -> None:
+    def func1(x: int, *args: P.args, **kwargs: P.kwargs) -> None:
         f(*args, **kwargs)
 
-    def bar(*args: P.args, **kwargs: P.kwargs) -> None:
-        foo(1, *args, **kwargs)  # Accepted
+    def func2(*args: P.args, **kwargs: P.kwargs) -> None:
+        func1(1, *args, **kwargs)  # Accepted
 
         # This should generate an error because keyword parameters
         # are not allowed in this situation.
-        foo(x=1, *args, **kwargs)  # Rejected
+        func1(x=1, *args, **kwargs)  # Rejected
 
-    return bar
+        # This should generate an error because *args is duplicated.
+        func1(1, *args, *args, **kwargs)
+
+        # This should generate an error because **kwargs is duplicated.
+        func1(1, *args, **kwargs, **kwargs)
+
+    return func2

packages/pyright-internal/src/tests/typeEvaluator4.test.ts

@@ -607,7 +607,7 @@ test('ParamSpec7', () => {
 
 test('ParamSpec8', () => {
     const results = TestUtils.typeAnalyzeSampleFiles(['paramSpec8.py']);
-    TestUtils.validateResults(results, 5);
+    TestUtils.validateResults(results, 7);
 });
 
 test('ParamSpec9', () => {
@@ -812,7 +812,7 @@ test('ParamSpec48', () => {
 
 test('ParamSpec49', () => {
     const results = TestUtils.typeAnalyzeSampleFiles(['paramSpec49.py']);
-    TestUtils.validateResults(results, 5);
+    TestUtils.validateResults(results, 7);
 });
 
 test('ParamSpec50', () => {