From e484d54fb83541853b334d25384855ad21db998d Mon Sep 17 00:00:00 2001
From: Anna Kozlova <anna.kozlova@jetbrains.com>
Date: Thu, 12 Nov 2015 12:29:08 +0100
Subject: [PATCH] missed usages of method references (IDEA-147828)

---
 .../impl/search/JavaFunctionalExpressionSearcher.java  |  3 ++-
 .../lambda/findUsages/ClassFromJdkMethodRef.java       | 10 ++++++++++
 .../daemon/lambda/FindFunctionalInterfaceTest.java     | 10 +++++++++-
 3 files changed, 21 insertions(+), 2 deletions(-)
 create mode 100644 java/java-tests/testData/codeInsight/daemonCodeAnalyzer/lambda/findUsages/ClassFromJdkMethodRef.java

diff --git a/java/java-indexing-impl/src/com/intellij/psi/impl/search/JavaFunctionalExpressionSearcher.java b/java/java-indexing-impl/src/com/intellij/psi/impl/search/JavaFunctionalExpressionSearcher.java
index 128b96f4b0af..f3cf54df5083 100644
--- a/java/java-indexing-impl/src/com/intellij/psi/impl/search/JavaFunctionalExpressionSearcher.java
+++ b/java/java-indexing-impl/src/com/intellij/psi/impl/search/JavaFunctionalExpressionSearcher.java
@@ -364,7 +364,8 @@ public class JavaFunctionalExpressionSearcher extends QueryExecutorBase<PsiFunct
     @Override
     public boolean process(VirtualFile file, Collection<JavaFunctionalExpressionIndex.IndexHolder> holders) {
       for (JavaFunctionalExpressionIndex.IndexHolder holder : holders) {
-        if (holder.getLambdaParamsNumber() == myExpectedFunExprParamsCount) {
+        final int lambdaParamsNumber = holder.getLambdaParamsNumber();
+        if (lambdaParamsNumber == myExpectedFunExprParamsCount || lambdaParamsNumber == -1) {
           final boolean suitableParamNumbers;
           if (myVarArgs) {
             suitableParamNumbers = holder.getMethodArgsLength() >= myParametersCount - 1;
diff --git a/java/java-tests/testData/codeInsight/daemonCodeAnalyzer/lambda/findUsages/ClassFromJdkMethodRef.java b/java/java-tests/testData/codeInsight/daemonCodeAnalyzer/lambda/findUsages/ClassFromJdkMethodRef.java
new file mode 100644
index 000000000000..40acbd56414a
--- /dev/null
+++ b/java/java-tests/testData/codeInsight/daemonCodeAnalyzer/lambda/findUsages/ClassFromJdkMethodRef.java
@@ -0,0 +1,10 @@
+class Test{
+
+  public void main(java.util.List<String> list) {
+    list.stream().filter(this::bar)
+  }
+  
+  public boolean bar() {
+    return true;
+  }
+}
\ No newline at end of file
diff --git a/java/java-tests/testSrc/com/intellij/codeInsight/daemon/lambda/FindFunctionalInterfaceTest.java b/java/java-tests/testSrc/com/intellij/codeInsight/daemon/lambda/FindFunctionalInterfaceTest.java
index 1018c0706831..fdccb3c34cdd 100644
--- a/java/java-tests/testSrc/com/intellij/codeInsight/daemon/lambda/FindFunctionalInterfaceTest.java
+++ b/java/java-tests/testSrc/com/intellij/codeInsight/daemon/lambda/FindFunctionalInterfaceTest.java
@@ -70,6 +70,14 @@ public class FindFunctionalInterfaceTest extends LightCodeInsightFixtureTestCase
   }
 
   public void testClassFromJdk() {
+    doTestIndexSearch("(e) -> true");
+  }
+
+  public void testClassFromJdkMethodRef() {
+    doTestIndexSearch("this::bar");
+  }
+
+  public void doTestIndexSearch(String expected) {
     myFixture.configureByFile(getTestName(false) + ".java");
 
     for (int i = 0; i < JavaFunctionalExpressionSearcher.SMART_SEARCH_THRESHOLD + 5; i++) {
@@ -79,7 +87,7 @@ public class FindFunctionalInterfaceTest extends LightCodeInsightFixtureTestCase
     PsiClass predicate = JavaPsiFacade.getInstance(getProject()).findClass(Predicate.class.getName(), GlobalSearchScope.allScope(getProject()));
     assert predicate != null;
     final PsiFunctionalExpression next = assertOneElement(FunctionalExpressionSearch.search(predicate).findAll());
-    assertEquals("(e) -> true", next.getText());
+    assertEquals(expected, next.getText());
   }
 
   @Override