From 5d77379fd36bc2b6e4913d2a154e1ee0f1759eb6 Mon Sep 17 00:00:00 2001
From: Anna Kozlova <anna.kozlova@jetbrains.com>
Date: Tue, 29 May 2018 20:51:26 +0300
Subject: [PATCH] create field from parameter even if parameter is already used
 in assignment

IDEA-192896
---
 .../impl/CreateFieldFromParameterAction.java  |  2 +-
 .../impl/FieldFromParameterUtils.java         | 27 ++++++++++++++++---
 .../afterAlreadyAssigned.java                 | 13 +++++++++
 .../beforeAlreadyAssigned.java                |  9 +++++++
 4 files changed, 47 insertions(+), 4 deletions(-)
 create mode 100644 java/java-tests/testData/codeInsight/daemonCodeAnalyzer/quickFix/createFieldFromParameter/afterAlreadyAssigned.java
 create mode 100644 java/java-tests/testData/codeInsight/daemonCodeAnalyzer/quickFix/createFieldFromParameter/beforeAlreadyAssigned.java

diff --git a/java/java-impl/src/com/intellij/codeInsight/intention/impl/CreateFieldFromParameterAction.java b/java/java-impl/src/com/intellij/codeInsight/intention/impl/CreateFieldFromParameterAction.java
index c41da34b4a38..21b62a0f1df9 100644
--- a/java/java-impl/src/com/intellij/codeInsight/intention/impl/CreateFieldFromParameterAction.java
+++ b/java/java-impl/src/com/intellij/codeInsight/intention/impl/CreateFieldFromParameterAction.java
@@ -32,7 +32,7 @@ public class CreateFieldFromParameterAction extends CreateFieldFromParameterActi
   protected boolean isAvailable(PsiParameter psiParameter) {
     final PsiType type = getSubstitutedType(psiParameter);
     final PsiClass targetClass = PsiTreeUtil.getParentOfType(psiParameter, PsiClass.class);
-    return FieldFromParameterUtils.isAvailable(psiParameter, type, targetClass) &&
+    return FieldFromParameterUtils.isAvailable(psiParameter, type, targetClass, false) &&
            psiParameter.getLanguage().isKindOf(JavaLanguage.INSTANCE);
   }
 
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 8168ae2fe60a..2f5e3e4e7415 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
@@ -109,10 +109,22 @@ public final class FieldFromParameterUtils {
 
   @Nullable
   public static PsiField getParameterAssignedToField(final PsiParameter parameter) {
+    return getParameterAssignedToField(parameter, true);
+  }
+
+  @Nullable
+  public static PsiField getParameterAssignedToField(final PsiParameter parameter, boolean findIndirectAssignments) {
     for (PsiReference reference : ReferencesSearch.search(parameter, new LocalSearchScope(parameter.getDeclarationScope()), false)) {
       if (!(reference instanceof PsiReferenceExpression)) continue;
       final PsiReferenceExpression expression = (PsiReferenceExpression)reference;
-      PsiAssignmentExpression assignmentExpression = PsiTreeUtil.getParentOfType(expression, PsiAssignmentExpression.class, true, PsiClass.class);
+      PsiAssignmentExpression assignmentExpression;
+      if (findIndirectAssignments) {
+        assignmentExpression = PsiTreeUtil.getParentOfType(expression, PsiAssignmentExpression.class, true, PsiClass.class);
+      }
+      else {
+        PsiElement parent = PsiUtil.skipParenthesizedExprUp(expression.getParent());
+        assignmentExpression = parent instanceof PsiAssignmentExpression ? (PsiAssignmentExpression)parent : null;
+      }
       if (assignmentExpression == null) continue;
       if (!PsiTreeUtil.isAncestor(assignmentExpression.getRExpression(), expression, false)) continue;
       final PsiExpression lExpression = assignmentExpression.getLExpression();
@@ -256,7 +268,16 @@ public final class FieldFromParameterUtils {
     }
   }
 
-  public static boolean isAvailable(@Nullable PsiParameter myParameter, @Nullable PsiType type, @Nullable PsiClass targetClass) {
+  public static boolean isAvailable(@Nullable PsiParameter myParameter,
+                                  @Nullable PsiType type,
+                                  @Nullable PsiClass targetClass) {
+    return isAvailable(myParameter, type, targetClass, true);
+  }
+
+  public static boolean isAvailable(@Nullable PsiParameter myParameter, 
+                                    @Nullable PsiType type, 
+                                    @Nullable PsiClass targetClass, 
+                                    boolean findIndirectAssignments) {
     return myParameter != null
            && myParameter.isValid()
            && myParameter.getManager().isInProject(myParameter)
@@ -266,7 +287,7 @@ public final class FieldFromParameterUtils {
            && type.isValid()
            && targetClass != null
            && !targetClass.isInterface()
-           && getParameterAssignedToField(myParameter) == null;
+           && getParameterAssignedToField(myParameter, findIndirectAssignments) == null;
   }
 
   private FieldFromParameterUtils() { }
diff --git a/java/java-tests/testData/codeInsight/daemonCodeAnalyzer/quickFix/createFieldFromParameter/afterAlreadyAssigned.java b/java/java-tests/testData/codeInsight/daemonCodeAnalyzer/quickFix/createFieldFromParameter/afterAlreadyAssigned.java
new file mode 100644
index 000000000000..09f7020a5315
--- /dev/null
+++ b/java/java-tests/testData/codeInsight/daemonCodeAnalyzer/quickFix/createFieldFromParameter/afterAlreadyAssigned.java
@@ -0,0 +1,13 @@
+// "Create field for parameter 'p1'" "true"
+
+class Test{
+    int b;
+    @org.jetbrains.annotations.NotNull
+    private final String myP1;
+
+    Test(String p1){
+        b = p1.length();
+        myP1 = p1;
+    }
+}
+
diff --git a/java/java-tests/testData/codeInsight/daemonCodeAnalyzer/quickFix/createFieldFromParameter/beforeAlreadyAssigned.java b/java/java-tests/testData/codeInsight/daemonCodeAnalyzer/quickFix/createFieldFromParameter/beforeAlreadyAssigned.java
new file mode 100644
index 000000000000..be50296fbff5
--- /dev/null
+++ b/java/java-tests/testData/codeInsight/daemonCodeAnalyzer/quickFix/createFieldFromParameter/beforeAlreadyAssigned.java
@@ -0,0 +1,9 @@
+// "Create field for parameter 'p1'" "true"
+
+class Test{
+    int b;
+    Test(String p<caret>1){
+        b = p1.length();
+    }
+}
+