add PyMethodOverridingInspection (PY-140)

python/src/com/jetbrains/python/PyBundle.properties

@@ -74,7 +74,10 @@ INSP.NAME.first.arg.assign=Reassignment of method's first argument
 INSP.first.arg.$0.assigned=Method''s parameter ''{0}'' reassigned
 
 # PyStringFormatInspection
-INSP.NAME.str.format=Detect errors in string formatting operations.
+INSP.NAME.str.format=Errors in string formatting operations
+
+# PyMethodOverridingInspection
+INSP.NAME.method.over=Method signature does not match signature of overridden method
 
 ### Annotators ###
 ANN.deleting.none=deleting None

python/src/com/jetbrains/python/inspections/PyMethodOverridingInspection.java

@@ -0,0 +1,82 @@
+package com.jetbrains.python.inspections;
+
+import com.intellij.codeInspection.LocalInspectionTool;
+import com.intellij.codeInspection.ProblemsHolder;
+import com.intellij.psi.PsiElement;
+import com.intellij.psi.PsiElementVisitor;
+import com.jetbrains.python.PyBundle;
+import com.jetbrains.python.psi.PyFunction;
+import com.jetbrains.python.psi.PyNamedParameter;
+import com.jetbrains.python.psi.PyParameter;
+import com.jetbrains.python.psi.search.PySuperMethodsSearch;
+import org.jetbrains.annotations.Nls;
+import org.jetbrains.annotations.NotNull;
+
+/**
+ * Created by IntelliJ IDEA.
+ * User: Alexey.Ivanov
+ * Date: Jul 28, 2009
+ * Time: 4:06:18 PM
+ */
+public class PyMethodOverridingInspection extends LocalInspectionTool {
+
+  @Nls
+  @NotNull
+  public String getGroupDisplayName() {
+    return PyBundle.message("INSP.GROUP.python");
+  }
+
+  @Nls
+  @NotNull
+  public String getDisplayName() {
+    return PyBundle.message("INSP.NAME.method.over");
+  }
+
+  @NotNull
+  public String getShortName() {
+    return "PyMethodOverridingInspection";
+  }
+
+  @Override
+  public boolean isEnabledByDefault() {
+    return true;
+  }
+
+  @NotNull
+  @Override
+  public PsiElementVisitor buildVisitor(@NotNull final ProblemsHolder holder, final boolean isOnTheFly) {
+    return new Visitor(holder);
+  }
+
+  public static class Visitor extends PyInspectionVisitor {
+
+    public Visitor(final ProblemsHolder holder) {
+      super(holder);
+    }
+
+    @Override
+    public void visitPyFunction(final PyFunction function) {
+      for (PsiElement psiElement : PySuperMethodsSearch.search(function)) {
+        final PyParameter[] parameters = function.getParameterList().getParameters();
+        if (psiElement instanceof PyFunction) {
+          final PyParameter[] superFunctionParameters = ((PyFunction)psiElement).getParameterList().getParameters();
+          if (parameters.length != superFunctionParameters.length) {
+            registerProblem(function.getParameterList(), "Number of parameters does not match parameters of base method");
+            return;
+          }
+
+          for (int i = 0; i < parameters.length; ++i) {
+            if (parameters[i] instanceof PyNamedParameter && superFunctionParameters[i] instanceof PyNamedParameter) {
+              final PyNamedParameter namedParameter = (PyNamedParameter)parameters[i];
+              final PyNamedParameter namedSuperFunctionParameter = (PyNamedParameter)superFunctionParameters[i];
+              if (namedParameter.isKeywordContainer() != namedSuperFunctionParameter.isKeywordContainer() ||
+                  namedParameter.isPositionalContainer() != namedSuperFunctionParameter.isPositionalContainer()) {
+                registerProblem(namedParameter, "Method signature does not match signature of base method");
+              }
+            }
+          }
+        }
+      }
+    }
+  }
+}

python/src/com/jetbrains/python/inspections/PythonInspectionToolProvider.java

@@ -16,7 +16,8 @@ public class PythonInspectionToolProvider implements InspectionToolProvider {
       PyMethodParametersInspection.class,
       PyUnreachableCodeInspection.class,
       PyMethodFirstArgAssignmentInspection.class,
-      PyStringFormatInspection.class
+      PyStringFormatInspection.class,
+      PyMethodOverridingInspection.class
     };
   }
 }

python/testData/inspections/PyMethodOverridingInspection/expected.xml

@@ -0,0 +1,18 @@
+<?xml version="1.0" encoding="UTF-8"?>
+<problems>
+  <problem>
+    <file>method-overriding.py</file>
+    <line>6</line>
+    <description>Method signature does not match signature of base method</description>
+  </problem>
+  <problem>
+    <file>method-overriding.py</file>
+    <line>10</line>
+    <description>Number of parameters does not match parameters of base method</description>
+  </problem>
+  <problem>
+    <file>method-overriding.py</file>
+    <line>14</line>
+    <description>Method signature does not match signature of base method</description>
+  </problem>
+</problems>

python/testSrc/com/jetbrains/python/PythonInspectionsTest.java

@@ -50,6 +50,11 @@ public class PythonInspectionsTest extends PyLightFixtureTestCase {
     doTest(getTestName(false), inspection);
   }
 
+  public void testPyMethodOverridingInspection() throws Throwable {
+    LocalInspectionTool inspection = new PyMethodOverridingInspection();
+    doTest(getTestName(false), inspection);
+  }
+
   protected String getTestDataPath() {
     return PathManager.getHomePath() + "/plugins/python/testData/inspections/";
   }