From ff958e1fdd61a6e5fcdbe297b85b384589e9d68d Mon Sep 17 00:00:00 2001
From: Pavel Dolgov <pavel.dolgov@jetbrains.com>
Date: Mon, 9 Jul 2018 13:05:23 +0300
Subject: [PATCH] Java: Preserve comments when extracting method with
 duplicates (IDEA-194463)

---
 .../extractMethod/ParametrizedDuplicates.java   |  4 ++--
 .../DuplicatePreserveComments.java              | 13 +++++++++++++
 .../DuplicatePreserveComments_after.java        | 17 +++++++++++++++++
 .../java/refactoring/ExtractMethodTest.java     |  4 ++++
 4 files changed, 36 insertions(+), 2 deletions(-)
 create mode 100644 java/java-tests/testData/refactoring/extractMethod/DuplicatePreserveComments.java
 create mode 100644 java/java-tests/testData/refactoring/extractMethod/DuplicatePreserveComments_after.java

diff --git a/java/java-impl/src/com/intellij/refactoring/extractMethod/ParametrizedDuplicates.java b/java/java-impl/src/com/intellij/refactoring/extractMethod/ParametrizedDuplicates.java
index 153257c7b31d..382082cf7f6c 100644
--- a/java/java-impl/src/com/intellij/refactoring/extractMethod/ParametrizedDuplicates.java
+++ b/java/java-impl/src/com/intellij/refactoring/extractMethod/ParametrizedDuplicates.java
@@ -57,8 +57,8 @@ public class ParametrizedDuplicates {
 
   private ParametrizedDuplicates(@NotNull PsiElement[] pattern,
                                  @NotNull ExtractMethodProcessor originalProcessor) {
-    pattern = getFilteredElements(pattern);
-    PsiElement firstElement = pattern.length != 0 ? pattern[0] : null;
+    PsiElement[] filteredPattern = getFilteredElements(pattern);
+    PsiElement firstElement = filteredPattern.length != 0 ? filteredPattern[0] : null;
     if (firstElement instanceof PsiStatement) {
       PsiElement[] copy = copyElements(pattern);
       myElements = wrapWithCodeBlock(copy, originalProcessor.getInputVariables());
diff --git a/java/java-tests/testData/refactoring/extractMethod/DuplicatePreserveComments.java b/java/java-tests/testData/refactoring/extractMethod/DuplicatePreserveComments.java
new file mode 100644
index 000000000000..9e490316aed5
--- /dev/null
+++ b/java/java-tests/testData/refactoring/extractMethod/DuplicatePreserveComments.java
@@ -0,0 +1,13 @@
+class C {
+    void foo() {
+        <selection>/*a*/ // b
+        System.out.println(1);
+        /*c*/ // d</selection>
+    }
+
+    void bar() {
+        /*x*/
+        System.out.println(1);
+        /*z*/
+    }
+}
\ No newline at end of file
diff --git a/java/java-tests/testData/refactoring/extractMethod/DuplicatePreserveComments_after.java b/java/java-tests/testData/refactoring/extractMethod/DuplicatePreserveComments_after.java
new file mode 100644
index 000000000000..d1657300d5dc
--- /dev/null
+++ b/java/java-tests/testData/refactoring/extractMethod/DuplicatePreserveComments_after.java
@@ -0,0 +1,17 @@
+class C {
+    void foo() {
+        newMethod();
+    }
+
+    private void newMethod() {
+        /*a*/ // b
+        System.out.println(1);
+        /*c*/ // d
+    }
+
+    void bar() {
+        /*x*/
+        newMethod();
+        /*z*/
+    }
+}
\ No newline at end of file
diff --git a/java/java-tests/testSrc/com/intellij/java/refactoring/ExtractMethodTest.java b/java/java-tests/testSrc/com/intellij/java/refactoring/ExtractMethodTest.java
index e23854f8944d..c4f512d268a7 100644
--- a/java/java-tests/testSrc/com/intellij/java/refactoring/ExtractMethodTest.java
+++ b/java/java-tests/testSrc/com/intellij/java/refactoring/ExtractMethodTest.java
@@ -1287,6 +1287,10 @@ public class ExtractMethodTest extends LightCodeInsightTestCase {
     doDuplicatesTest();
   }
 
+  public void testDuplicatePreserveComments() throws Exception {
+    doDuplicatesTest();
+  }
+
   public void testBeforeCommentAfterSelectedFragment() throws Exception {
     doTest();
   }