redundant type args: check boxed types if javac would be able to compile (IDEA-53984)

java/java-impl/src/com/intellij/codeInspection/miscGenerics/RedundantTypeArgsInspection.java

@@ -20,6 +20,7 @@ import com.intellij.codeInspection.*;
 import com.intellij.openapi.diagnostic.Logger;
 import com.intellij.openapi.project.Project;
 import com.intellij.psi.*;
+import com.intellij.psi.util.PsiUtil;
 import com.intellij.util.IncorrectOperationException;
 import org.jetbrains.annotations.NotNull;
 
@@ -105,6 +106,7 @@ public class RedundantTypeArgsInspection extends GenericsInspectionToolBase {
                                                                                         argumentList.getExpressions(),
                                                                                         resolveResult.getSubstitutor(), expression, false);
               if (!typeArguments[i].equals(inferedType)) return;
+              if (PsiUtil.resolveClassInType(method.getReturnType()) == typeParameter && PsiPrimitiveType.getUnboxedType(inferedType) != null) return;
             }
 
             final PsiCallExpression copy = (PsiCallExpression)expression.copy(); //see IDEADEV-8174

java/java-tests/testData/inspection/redundantTypeArgs/ReturnPrimitiveTypes.java

@@ -0,0 +1,12 @@
+import java.util.*;
+class Test {
+  Map someMap;
+
+  public int getGetBar() {
+    return this.<Integer>getFoo("numberOfConfigurations");
+  }
+
+  protected <T> T getFoo(String key) {
+    return (T)someMap.get(key);
+  }
+}

java/java-tests/testSrc/com/intellij/codeInspection/RedundantTypeArgsInspectionTest.java

@@ -0,0 +1,32 @@
+/*
+ * User: anna
+ * Date: 19-Apr-2010
+ */
+package com.intellij.codeInspection;
+
+import com.intellij.JavaTestUtil;
+import com.intellij.codeInspection.miscGenerics.RedundantTypeArgsInspection;
+import com.intellij.testFramework.builders.JavaModuleFixtureBuilder;
+import com.intellij.testFramework.fixtures.JavaCodeInsightFixtureTestCase;
+
+public class RedundantTypeArgsInspectionTest extends JavaCodeInsightFixtureTestCase {
+  @Override
+  protected void tuneFixture(JavaModuleFixtureBuilder moduleBuilder) {
+    moduleBuilder.setMockJdkLevel(JavaModuleFixtureBuilder.MockJdkLevel.jdk15);
+  }
+
+  @Override
+  protected String getTestDataPath() {
+    return JavaTestUtil.getJavaTestDataPath() + "/inspection/redundantTypeArgs/";
+  }
+
+  private void doTest() throws Throwable {
+    final RedundantTypeArgsInspection inspection = new RedundantTypeArgsInspection();
+    myFixture.enableInspections(inspection);
+    myFixture.testHighlighting(true, false, false, getTestName(false) + ".java");
+  }
+
+  public void testReturnPrimitiveTypes() throws Throwable { // javac non-boxing: IDEA-53984
+    doTest();
+  }
+}