From ba90fcc173ea4f47c2a1a02b6d0e00fbce2ef134 Mon Sep 17 00:00:00 2001
From: Bas Leijdekkers <basleijdekkers@gmail.com>
Date: Thu, 19 Sep 2024 16:45:07 +0200
Subject: [PATCH] Java: make auto-import action available on method references
 to non-static methods (IDEA-336191)

GitOrigin-RevId: 2441af053858efe56887a5ea8dc34cfd08878261
---
 .../impl/quickfix/ImportClassFixBase.java     | 12 ++++++-----
 .../intention/AddImportActionTest.java        | 21 ++++++++++++++++++-
 2 files changed, 27 insertions(+), 6 deletions(-)

diff --git a/java/java-impl/src/com/intellij/codeInsight/daemon/impl/quickfix/ImportClassFixBase.java b/java/java-impl/src/com/intellij/codeInsight/daemon/impl/quickfix/ImportClassFixBase.java
index 320d3c6270c3..c3056f248640 100644
--- a/java/java-impl/src/com/intellij/codeInsight/daemon/impl/quickfix/ImportClassFixBase.java
+++ b/java/java-impl/src/com/intellij/codeInsight/daemon/impl/quickfix/ImportClassFixBase.java
@@ -194,8 +194,8 @@ public abstract class ImportClassFixBase<T extends PsiElement, R extends PsiRefe
                                   facade.arePackagesTheSame(aClass, myReferenceElement) ||
                                   PsiTreeUtil.getParentOfType(aClass, PsiImplicitClass.class) != null) &&
                                  !isAccessible(aClass, myReferenceElement));
-
-    filterByRequiredMemberName(classList);
+    boolean needsStatic = !(parent instanceof PsiMethodReferenceExpression);
+    filterByRequiredMemberName(classList, needsStatic);
 
     Collection<PsiClass> filtered = filterByContext(classList, myReferenceElement);
     if (!filtered.isEmpty()) {
@@ -248,18 +248,20 @@ public abstract class ImportClassFixBase<T extends PsiElement, R extends PsiRefe
     return true;
   }
 
-  private void filterByRequiredMemberName(@NotNull List<PsiClass> classList) {
+  private void filterByRequiredMemberName(@NotNull List<PsiClass> classList, boolean needsStatic) {
     String memberName = getRequiredMemberName(myReferenceElement);
     if (memberName != null) {
       classList.removeIf(psiClass -> {
         PsiField field = psiClass.findFieldByName(memberName, true);
-        if (field != null && field.hasModifierProperty(PsiModifier.STATIC) && isAccessible(field, myReferenceElement)) return false;
+        if (field != null && (!needsStatic || field.hasModifierProperty(PsiModifier.STATIC)) && isAccessible(field, myReferenceElement)) {
+          return false;
+        }
 
         PsiClass inner = psiClass.findInnerClassByName(memberName, true);
         if (inner != null && isAccessible(inner, myReferenceElement)) return false;
 
         for (PsiMethod method : psiClass.findMethodsByName(memberName, true)) {
-          if (method.hasModifierProperty(PsiModifier.STATIC) && isAccessible(method, myReferenceElement)) return false;
+          if ((!needsStatic || method.hasModifierProperty(PsiModifier.STATIC)) && isAccessible(method, myReferenceElement)) return false;
         }
         return true;
       });
diff --git a/java/java-tests/testSrc/com/intellij/java/codeInsight/intention/AddImportActionTest.java b/java/java-tests/testSrc/com/intellij/java/codeInsight/intention/AddImportActionTest.java
index d4af7972b593..b11a37bffddc 100644
--- a/java/java-tests/testSrc/com/intellij/java/codeInsight/intention/AddImportActionTest.java
+++ b/java/java-tests/testSrc/com/intellij/java/codeInsight/intention/AddImportActionTest.java
@@ -1,10 +1,11 @@
-// Copyright 2000-2023 JetBrains s.r.o. and contributors. Use of this source code is governed by the Apache 2.0 license.
+// Copyright 2000-2024 JetBrains s.r.o. and contributors. Use of this source code is governed by the Apache 2.0 license.
 package com.intellij.java.codeInsight.intention;
 
 import com.intellij.application.options.CodeStyle;
 import com.intellij.codeInsight.daemon.impl.quickfix.ImportClassFix;
 import com.intellij.codeInsight.intention.IntentionAction;
 import com.intellij.codeInsight.intention.IntentionActionDelegate;
+import com.intellij.ide.highlighter.JavaFileType;
 import com.intellij.lang.java.JavaLanguage;
 import com.intellij.openapi.application.impl.NonBlockingReadActionImpl;
 import com.intellij.pom.java.JavaFeature;
@@ -75,6 +76,24 @@ public class AddImportActionTest extends LightJavaCodeInsightFixtureTestCase {
                             """);
   }
 
+  public void testMethodReference() {
+    myFixture.configureByText(JavaFileType.INSTANCE, """
+      public class Importing {
+          void x(List<Object> list) {
+              list.stream().map(Random.class::cast).map(Ra<caret>ndom::toString).forEach(System.out::println);
+          }
+      }""");
+    importClass();
+    myFixture.checkResult("""
+                            import java.util.Random;
+                            
+                            public class Importing {
+                                void x(List<Object> list) {
+                                    list.stream().map(Random.class::cast).map(Random::toString).forEach(System.out::println);
+                                }
+                            }""");
+  }
+
   public void testStringValue() {
     myFixture.addClass("package java.lang; class StringValue {}");
     myFixture.addClass("package foo; public class StringValue {}");