introduce constant check (IDEA-189238)

method references by second search would be called on lambda parameter so should not influence constant checks

java/java-impl/src/com/intellij/refactoring/introduceField/IntroduceConstantHandler.java

@@ -249,6 +249,13 @@ public class IntroduceConstantHandler extends BaseExpressionToFieldHandler {
       }
     }
 
+    @Override
+    public void visitMethodReferenceExpression(PsiMethodReferenceExpression expression) {
+      if (!PsiMethodReferenceUtil.isResolvedBySecondSearch(expression)) {
+        super.visitMethodReferenceExpression(expression);
+      }
+    }
+
     @Override
     public void visitCallExpression(PsiCallExpression callExpression) {
       super.visitCallExpression(callExpression);

java/java-psi-api/src/com/intellij/psi/PsiMethodReferenceUtil.java

@@ -38,6 +38,23 @@ public class PsiMethodReferenceUtil {
     return false;
   }
 
+  public static boolean isResolvedBySecondSearch(@NotNull PsiMethodReferenceExpression methodRef) {
+    PsiElement resolve = methodRef.resolve();
+    if (resolve instanceof PsiMethod) {
+      PsiMethod method = (PsiMethod)resolve;
+      PsiType functionalInterfaceType = methodRef.getFunctionalInterfaceType();
+      PsiClassType.ClassResolveResult functionalResolveResult = PsiUtil.resolveGenericsClassInType(functionalInterfaceType);
+      final PsiMethod interfaceMethod = LambdaUtil.getFunctionalInterfaceMethod(functionalResolveResult);
+      return interfaceMethod != null &&
+             isResolvedBySecondSearch(methodRef,
+                                      interfaceMethod.getSignature(LambdaUtil.getSubstitutor(interfaceMethod, functionalResolveResult)),
+                                      method.isVarArgs(),
+                                      method.hasModifierProperty(PsiModifier.STATIC),
+                                      method.getParameterList().getParametersCount());
+    }
+    return false;
+  }
+
   public static boolean isResolvedBySecondSearch(@NotNull PsiMethodReferenceExpression methodRef,
                                                  @Nullable MethodSignature signature,
                                                  boolean varArgs,

java/java-tests/testData/refactoring/introduceConstant/WithMethodReferenceBySecondSearch.java

@@ -0,0 +1,14 @@
+
+import java.util.Comparator;
+
+class Foo implements Comparable<Foo> {
+
+    public String getName() {
+        return "";
+    }
+
+    @Override
+    public int compareTo(final Foo o) {
+        return <selection>Comparator.comparing(Foo::getName, String.CASE_INSENSITIVE_ORDER)</selection>.compare(this, o);
+    }
+}

java/java-tests/testData/refactoring/introduceConstant/WithMethodReferenceBySecondSearch_after.java

@@ -0,0 +1,16 @@
+
+import java.util.Comparator;
+
+class Foo implements Comparable<Foo> {
+
+    public static final Comparator<Foo> xxx = Comparator.comparing(Foo::getName, String.CASE_INSENSITIVE_ORDER);
+
+    public String getName() {
+        return "";
+    }
+
+    @Override
+    public int compareTo(final Foo o) {
+        return xxx.compare(this, o);
+    }
+}

java/java-tests/testSrc/com/intellij/java/refactoring/IntroduceConstantTest.java

@@ -160,6 +160,12 @@ public class IntroduceConstantTest extends LightCodeInsightTestCase {
     checkResultByFile(BASE_PATH + getTestName(false) + "_after.java");
   }
 
+  public void testWithMethodReferenceBySecondSearch() {
+    configureByFile(BASE_PATH + getTestName(false) + ".java");
+    new MockIntroduceConstantHandler(null).invoke(getProject(), getEditor(), getFile(), null);
+    checkResultByFile(BASE_PATH + getTestName(false) + "_after.java");
+  }
+
   public void testComments() {
     doTestExpr();
   }