From 309dd061f07fb423fd952599089d4ffa781cbd4e Mon Sep 17 00:00:00 2001
From: Semyon Proshev <Semyon.Proshev@jetbrains.com>
Date: Wed, 9 Nov 2016 19:28:02 +0300
Subject: [PATCH] Support type checking for positional arguments

---
 .../inspections/PyTypeCheckerInspection.java  | 27 +++++++++++++++----
 .../PositionalArguments.py                    |  8 ++++++
 .../PyTypeCheckerInspectionTest.java          |  4 +++
 3 files changed, 34 insertions(+), 5 deletions(-)
 create mode 100644 python/testData/inspections/PyTypeCheckerInspection/PositionalArguments.py

diff --git a/python/src/com/jetbrains/python/inspections/PyTypeCheckerInspection.java b/python/src/com/jetbrains/python/inspections/PyTypeCheckerInspection.java
index 0ff3c667f448..bef8c9c0f5ba 100644
--- a/python/src/com/jetbrains/python/inspections/PyTypeCheckerInspection.java
+++ b/python/src/com/jetbrains/python/inspections/PyTypeCheckerInspection.java
@@ -31,6 +31,7 @@ import com.jetbrains.python.codeInsight.dataflow.scope.ScopeUtil;
 import com.jetbrains.python.documentation.PythonDocumentationProvider;
 import com.jetbrains.python.inspections.quickfix.PyMakeFunctionReturnTypeQuickFix;
 import com.jetbrains.python.psi.*;
+import com.jetbrains.python.psi.impl.PyBuiltinCache;
 import com.jetbrains.python.psi.types.*;
 import org.jetbrains.annotations.Nls;
 import org.jetbrains.annotations.NotNull;
@@ -203,19 +204,19 @@ public class PyTypeCheckerInspection extends PyInspection {
       for (Map.Entry<PyExpression, PyNamedParameter> entry : mapping.entrySet()) {
         final PyNamedParameter param = entry.getValue();
         final PyExpression arg = entry.getKey();
-        if (param.isPositionalContainer() || param.isKeywordContainer()) {
+        if (param.isKeywordContainer()) {
           continue;
         }
-        final PyType paramType = myTypeEvalContext.getType(param);
-        if (paramType == null) {
+        final PyType expectedArgType = getExpectedArgumentType(param);
+        if (expectedArgType == null) {
           continue;
         }
-        final PyType argType = myTypeEvalContext.getType(arg);
+        final PyType actualArgType = myTypeEvalContext.getType(arg);
         if (!genericsCollected) {
           substitutions.putAll(PyTypeChecker.unifyReceiver(receiver, myTypeEvalContext));
           genericsCollected = true;
         }
-        final Pair<String, ProblemHighlightType> problem = checkTypes(paramType, argType, myTypeEvalContext, substitutions);
+        final Pair<String, ProblemHighlightType> problem = checkTypes(expectedArgType, actualArgType, myTypeEvalContext, substitutions);
         if (problem != null) {
           problems.put(arg, problem);
         }
@@ -223,6 +224,22 @@ public class PyTypeCheckerInspection extends PyInspection {
       return problems;
     }
 
+    @Nullable
+    private PyType getExpectedArgumentType(@NotNull PyNamedParameter param) {
+      final PyType paramType = myTypeEvalContext.getType(param);
+
+      if (param.isPositionalContainer()) {
+        if (paramType == PyBuiltinCache.getInstance(param).getTupleType()) {
+          return null;
+        }
+        else if (paramType instanceof PyCollectionType) {
+          return ((PyCollectionType)paramType).getIteratedItemType();
+        }
+      }
+
+      return paramType;
+    }
+
     @Nullable
     private static Pair<String, ProblemHighlightType> checkTypes(@Nullable PyType expected,
                                                                  @Nullable PyType actual,
diff --git a/python/testData/inspections/PyTypeCheckerInspection/PositionalArguments.py b/python/testData/inspections/PyTypeCheckerInspection/PositionalArguments.py
new file mode 100644
index 000000000000..1d2eb2d5daf7
--- /dev/null
+++ b/python/testData/inspections/PyTypeCheckerInspection/PositionalArguments.py
@@ -0,0 +1,8 @@
+def foo(*args):
+    """
+    :type args: tuple[str]
+    """
+    pass
+
+
+foo(<warning descr="Expected type 'str', got 'int' instead">1</warning>, '1')
diff --git a/python/testSrc/com/jetbrains/python/inspections/PyTypeCheckerInspectionTest.java b/python/testSrc/com/jetbrains/python/inspections/PyTypeCheckerInspectionTest.java
index b73f19a9c8ed..32f4f7ff39a1 100644
--- a/python/testSrc/com/jetbrains/python/inspections/PyTypeCheckerInspectionTest.java
+++ b/python/testSrc/com/jetbrains/python/inspections/PyTypeCheckerInspectionTest.java
@@ -346,4 +346,8 @@ public class PyTypeCheckerInspectionTest extends PyTestCase {
   public void testMapArgumentsInOppositeOrder() {
     doTest();
   }
+
+  public void testPositionalArguments() {
+    doTest();
+  }
 }