From 307a7c774cfdc16fab9198384c5971d55b005701 Mon Sep 17 00:00:00 2001
From: Pavel Dolgov <pavel.dolgov@jetbrains.com>
Date: Wed, 6 Dec 2017 20:35:23 +0300
Subject: [PATCH] Java: Preserve comment from removed redundant variable
 (IDEA-182669)

---
 .../ReturnSeparatedFromComputationInspection.java   | 11 ++++++++++-
 .../afterCommentInVariableDeclaration.java          |  8 ++++++++
 .../afterCommentInVariableDeclaration2.java         | 12 ++++++++++++
 .../beforeCommentInVariableDeclaration.java         |  9 +++++++++
 .../beforeCommentInVariableDeclaration2.java        | 13 +++++++++++++
 5 files changed, 52 insertions(+), 1 deletion(-)
 create mode 100644 java/java-tests/testData/codeInsight/daemonCodeAnalyzer/quickFix/returnSeparatedFromComputation/afterCommentInVariableDeclaration.java
 create mode 100644 java/java-tests/testData/codeInsight/daemonCodeAnalyzer/quickFix/returnSeparatedFromComputation/afterCommentInVariableDeclaration2.java
 create mode 100644 java/java-tests/testData/codeInsight/daemonCodeAnalyzer/quickFix/returnSeparatedFromComputation/beforeCommentInVariableDeclaration.java
 create mode 100644 java/java-tests/testData/codeInsight/daemonCodeAnalyzer/quickFix/returnSeparatedFromComputation/beforeCommentInVariableDeclaration2.java

diff --git a/java/java-impl/src/com/intellij/codeInspection/intermediaryVariable/ReturnSeparatedFromComputationInspection.java b/java/java-impl/src/com/intellij/codeInspection/intermediaryVariable/ReturnSeparatedFromComputationInspection.java
index 7fe120f7a7d6..f73538d3737c 100644
--- a/java/java-impl/src/com/intellij/codeInspection/intermediaryVariable/ReturnSeparatedFromComputationInspection.java
+++ b/java/java-impl/src/com/intellij/codeInspection/intermediaryVariable/ReturnSeparatedFromComputationInspection.java
@@ -217,15 +217,24 @@ public class ReturnSeparatedFromComputationInspection extends AbstractBaseJavaLo
         return;
       }
     }
+    PsiExpression firstInlined = null;
     boolean isSingleUsage = value != null && usages.size() == 1;
     if (isSimple || isSingleUsage) {
       for (PsiReference usage : usages) {
         PsiExpression inlined = InlineUtil.inlineVariable(context.returnedVariable, value, (PsiJavaCodeReferenceElement)usage);
+        if (firstInlined == null) firstInlined = inlined;
         highlighter.add(inlined);
       }
     }
     if (isSimple || isSingleUsage || usages.isEmpty()) {
-      context.returnedVariable.delete();
+      CommentTracker tracker = new CommentTracker();
+      if (firstInlined != null) {
+        tracker.delete(context.returnedVariable);
+        tracker.insertCommentsBefore(firstInlined);
+      }
+      else {
+        tracker.deleteAndRestoreComments(context.returnedVariable);
+      }
     }
   }
 
diff --git a/java/java-tests/testData/codeInsight/daemonCodeAnalyzer/quickFix/returnSeparatedFromComputation/afterCommentInVariableDeclaration.java b/java/java-tests/testData/codeInsight/daemonCodeAnalyzer/quickFix/returnSeparatedFromComputation/afterCommentInVariableDeclaration.java
new file mode 100644
index 000000000000..1e3aaa4bd361
--- /dev/null
+++ b/java/java-tests/testData/codeInsight/daemonCodeAnalyzer/quickFix/returnSeparatedFromComputation/afterCommentInVariableDeclaration.java
@@ -0,0 +1,8 @@
+// "Move 'return' closer to computation of the value of 'n'" "true"
+class T {
+    int f(int k) {
+        if (k == 1)
+            return 1;
+        return /*comment1*/ -1;
+    }
+}
\ No newline at end of file
diff --git a/java/java-tests/testData/codeInsight/daemonCodeAnalyzer/quickFix/returnSeparatedFromComputation/afterCommentInVariableDeclaration2.java b/java/java-tests/testData/codeInsight/daemonCodeAnalyzer/quickFix/returnSeparatedFromComputation/afterCommentInVariableDeclaration2.java
new file mode 100644
index 000000000000..6df094816a04
--- /dev/null
+++ b/java/java-tests/testData/codeInsight/daemonCodeAnalyzer/quickFix/returnSeparatedFromComputation/afterCommentInVariableDeclaration2.java
@@ -0,0 +1,12 @@
+// "Move 'return' closer to computation of the value of 'n'" "true"
+class T {
+    int f(int k) {
+        if (k == 1)
+            return 1;
+        else if (k == 2)
+            return /*comment1*/ -1;
+        else if (k == 3)
+            return 3;
+        return -1;
+    }
+}
\ No newline at end of file
diff --git a/java/java-tests/testData/codeInsight/daemonCodeAnalyzer/quickFix/returnSeparatedFromComputation/beforeCommentInVariableDeclaration.java b/java/java-tests/testData/codeInsight/daemonCodeAnalyzer/quickFix/returnSeparatedFromComputation/beforeCommentInVariableDeclaration.java
new file mode 100644
index 000000000000..13fed68f9860
--- /dev/null
+++ b/java/java-tests/testData/codeInsight/daemonCodeAnalyzer/quickFix/returnSeparatedFromComputation/beforeCommentInVariableDeclaration.java
@@ -0,0 +1,9 @@
+// "Move 'return' closer to computation of the value of 'n'" "true"
+class T {
+    int f(int k) {
+        int n = /*comment1*/-1;
+        if (k == 1)
+            n = 1;
+        <caret>return n;
+    }
+}
\ No newline at end of file
diff --git a/java/java-tests/testData/codeInsight/daemonCodeAnalyzer/quickFix/returnSeparatedFromComputation/beforeCommentInVariableDeclaration2.java b/java/java-tests/testData/codeInsight/daemonCodeAnalyzer/quickFix/returnSeparatedFromComputation/beforeCommentInVariableDeclaration2.java
new file mode 100644
index 000000000000..61629ddc058f
--- /dev/null
+++ b/java/java-tests/testData/codeInsight/daemonCodeAnalyzer/quickFix/returnSeparatedFromComputation/beforeCommentInVariableDeclaration2.java
@@ -0,0 +1,13 @@
+// "Move 'return' closer to computation of the value of 'n'" "true"
+class T {
+    int f(int k) {
+        int n = /*comment1*/-1;
+        if (k == 1)
+            n = 1;
+        else if (k == 2)
+            return n;
+        else if (k == 3)
+            return 3;
+        <caret>return n;
+    }
+}
\ No newline at end of file