From 9e8666f15974d06c2800590259b1dbe9fabb7456 Mon Sep 17 00:00:00 2001
From: "Anna.Kozlova" <anna.kozlova@jetbrains.com>
Date: Wed, 23 Mar 2016 15:23:23 +0100
Subject: [PATCH] bind params to fields: accept field assignments if not
 exactly the parameter reference was assigned (IDEA-120320)

---
 .../impl/FieldFromParameterUtils.java         | 24 ++++++++++++-------
 .../afterPositionAfter.java                   | 11 +++++++++
 .../beforePositionAfter.java                  | 10 ++++++++
 3 files changed, 36 insertions(+), 9 deletions(-)
 create mode 100644 java/java-tests/testData/codeInsight/daemonCodeAnalyzer/quickFix/assignFieldFromParameter/afterPositionAfter.java
 create mode 100644 java/java-tests/testData/codeInsight/daemonCodeAnalyzer/quickFix/assignFieldFromParameter/beforePositionAfter.java

diff --git a/java/java-impl/src/com/intellij/codeInsight/intention/impl/FieldFromParameterUtils.java b/java/java-impl/src/com/intellij/codeInsight/intention/impl/FieldFromParameterUtils.java
index 3160a2bb45c3..b2bc06e28f62 100644
--- a/java/java-impl/src/com/intellij/codeInsight/intention/impl/FieldFromParameterUtils.java
+++ b/java/java-impl/src/com/intellij/codeInsight/intention/impl/FieldFromParameterUtils.java
@@ -145,19 +145,25 @@ public final class FieldFromParameterUtils {
         else if (expression instanceof PsiAssignmentExpression) {
           PsiAssignmentExpression assignmentExpression = (PsiAssignmentExpression)expression;
           PsiExpression lExpression = assignmentExpression.getLExpression();
-          PsiExpression rExpression = assignmentExpression.getRExpression();
 
           if (!(lExpression instanceof PsiReferenceExpression)) break;
-          if (!(rExpression instanceof PsiReferenceExpression)) break;
-
-          PsiReferenceExpression lReference = (PsiReferenceExpression)lExpression;
-          PsiReferenceExpression rReference = (PsiReferenceExpression)rExpression;
-
-          PsiElement lElement = lReference.resolve();
-          PsiElement rElement = rReference.resolve();
 
+          PsiElement lElement = ((PsiReferenceExpression)lExpression).resolve();
           if (!(lElement instanceof PsiField) || ((PsiField)lElement).getContainingClass() != targetClass) break;
-          if (!(rElement instanceof PsiParameter)) break;
+
+          final Set<PsiParameter> parameters = new HashSet<>();
+          SyntaxTraverser.psiTraverser().withRoot(assignmentExpression.getRExpression())
+            .filter(PsiReferenceExpression.class)
+            .forEach(expr -> {
+              final PsiElement resolve = expr.resolve();
+              if (resolve instanceof PsiParameter && ((PsiParameter)resolve).getDeclarationScope() == myParameter.getDeclarationScope()) {
+                parameters.add((PsiParameter)resolve);
+              }
+            });
+
+          if (parameters.size() != 1) break;
+
+          PsiElement rElement = parameters.iterator().next();
 
           if (myParameter.getTextRange().getStartOffset() < rElement.getTextRange().getStartOffset()) {
             if (anchorRef != null) {
diff --git a/java/java-tests/testData/codeInsight/daemonCodeAnalyzer/quickFix/assignFieldFromParameter/afterPositionAfter.java b/java/java-tests/testData/codeInsight/daemonCodeAnalyzer/quickFix/assignFieldFromParameter/afterPositionAfter.java
new file mode 100644
index 000000000000..d7d2684fc282
--- /dev/null
+++ b/java/java-tests/testData/codeInsight/daemonCodeAnalyzer/quickFix/assignFieldFromParameter/afterPositionAfter.java
@@ -0,0 +1,11 @@
+// "Assign Parameter to Field 'myId'" "true"
+
+class Person {
+    int a;
+    int myId;
+    void f(int a, int id) {
+        this.a = foo(a);
+        myId = id;
+    }
+    int foo(int a) {return a;}
+}
\ No newline at end of file
diff --git a/java/java-tests/testData/codeInsight/daemonCodeAnalyzer/quickFix/assignFieldFromParameter/beforePositionAfter.java b/java/java-tests/testData/codeInsight/daemonCodeAnalyzer/quickFix/assignFieldFromParameter/beforePositionAfter.java
new file mode 100644
index 000000000000..4f7d9fe7b720
--- /dev/null
+++ b/java/java-tests/testData/codeInsight/daemonCodeAnalyzer/quickFix/assignFieldFromParameter/beforePositionAfter.java
@@ -0,0 +1,10 @@
+// "Assign Parameter to Field 'myId'" "true"
+
+class Person {
+    int a;
+    int myId;
+    void f(int a, int id<caret>) {
+        this.a = foo(a);
+    }
+    int foo(int a) {return a;}
+}
\ No newline at end of file