From f4993e6f99843a11592df4ae4bb8918d694c2ecd Mon Sep 17 00:00:00 2001
From: Dmitry Batkovich <dmitry.batkovich@jetbrains.com>
Date: Mon, 13 Mar 2017 13:24:58 +0300
Subject: [PATCH] field initialization fix: add body for incomplete constructor

---
 .../InitializeFinalFieldInConstructorFix.java | 21 ++++++++++++-------
 .../afterIncompleteConstructor.java           |  8 +++++++
 .../beforeIncompleteConstructor.java          |  6 ++++++
 3 files changed, 27 insertions(+), 8 deletions(-)
 create mode 100644 java/java-tests/testData/codeInsight/daemonCodeAnalyzer/quickFix/initializeFinalFieldInConstructor/afterIncompleteConstructor.java
 create mode 100644 java/java-tests/testData/codeInsight/daemonCodeAnalyzer/quickFix/initializeFinalFieldInConstructor/beforeIncompleteConstructor.java

diff --git a/java/java-impl/src/com/intellij/codeInsight/daemon/impl/quickfix/InitializeFinalFieldInConstructorFix.java b/java/java-impl/src/com/intellij/codeInsight/daemon/impl/quickfix/InitializeFinalFieldInConstructorFix.java
index f99520fcac2f..c91d8e8752ea 100644
--- a/java/java-impl/src/com/intellij/codeInsight/daemon/impl/quickfix/InitializeFinalFieldInConstructorFix.java
+++ b/java/java-impl/src/com/intellij/codeInsight/daemon/impl/quickfix/InitializeFinalFieldInConstructorFix.java
@@ -22,6 +22,7 @@ import com.intellij.codeInsight.intention.IntentionAction;
 import com.intellij.codeInsight.lookup.LookupElement;
 import com.intellij.ide.util.MemberChooser;
 import com.intellij.openapi.application.ApplicationManager;
+import com.intellij.openapi.diagnostic.Logger;
 import com.intellij.openapi.editor.Editor;
 import com.intellij.openapi.project.Project;
 import com.intellij.psi.*;
@@ -31,6 +32,7 @@ import com.intellij.psi.search.searches.ReferencesSearch;
 import com.intellij.psi.util.PsiTreeUtil;
 import com.intellij.psi.util.PsiUtil;
 import com.intellij.util.IncorrectOperationException;
+import com.intellij.util.ObjectUtils;
 import org.jetbrains.annotations.NotNull;
 import org.jetbrains.annotations.Nullable;
 
@@ -40,6 +42,7 @@ import java.util.Collections;
 import java.util.List;
 
 public class InitializeFinalFieldInConstructorFix implements IntentionAction {
+  private static final Logger LOG = Logger.getInstance(InitializeFinalFieldInConstructorFix.class);
   private final PsiField myField;
 
   public InitializeFinalFieldInConstructorFix(@NotNull PsiField field) {
@@ -96,25 +99,27 @@ public class InitializeFinalFieldInConstructorFix implements IntentionAction {
                                              @Nullable Editor editor) {
     if (constructors.isEmpty()) return;
 
-    final List<PsiExpression> rExpressions = new ArrayList<>(constructors.size());
     final LookupElement[] suggestedInitializers = AddVariableInitializerFix.suggestInitializer(field);
 
+    final List<PsiExpression> rExpressions = new ArrayList<>(constructors.size());
     for (PsiMethod constructor : constructors) {
-      PsiExpression initialization = addFieldInitialization(constructor, suggestedInitializers, field, project);
-      if (initialization != null) {
-        rExpressions.add(initialization);
-      }
+      rExpressions.add(addFieldInitialization(constructor, suggestedInitializers, field, project));
     }
     AddVariableInitializerFix.runAssignmentTemplate(rExpressions, suggestedInitializers, editor);
   }
 
-  @Nullable
+  @NotNull
   private static PsiExpression addFieldInitialization(@NotNull PsiMethod constructor,
                                                       @NotNull LookupElement[] suggestedInitializers,
                                                       @NotNull PsiField field,
                                                       @NotNull Project project) {
     PsiCodeBlock methodBody = constructor.getBody();
-    if (methodBody == null) return null;
+    if (methodBody == null) {
+      //incomplete code
+      CreateFromUsageUtils.setupMethodBody(constructor);
+      methodBody = constructor.getBody();
+      LOG.assertTrue(methodBody != null);
+    }
 
     final String fieldName = field.getName();
     String stmtText = fieldName + " = " + suggestedInitializers[0].getPsiElement().getText() + ";";
@@ -128,7 +133,7 @@ public class InitializeFinalFieldInConstructorFix implements IntentionAction {
 
     final PsiExpressionStatement addedStatement = (PsiExpressionStatement)methodBody.add(codeStyleManager
       .reformat(factory.createStatementFromText(stmtText, methodBody)));
-    return ((PsiAssignmentExpression)addedStatement.getExpression()).getRExpression();
+    return ObjectUtils.notNull(((PsiAssignmentExpression)addedStatement.getExpression()).getRExpression());
   }
 
   private static boolean methodContainsParameterWithName(@NotNull PsiMethod constructor, @NotNull String name) {
diff --git a/java/java-tests/testData/codeInsight/daemonCodeAnalyzer/quickFix/initializeFinalFieldInConstructor/afterIncompleteConstructor.java b/java/java-tests/testData/codeInsight/daemonCodeAnalyzer/quickFix/initializeFinalFieldInConstructor/afterIncompleteConstructor.java
new file mode 100644
index 000000000000..c2fd7a905da8
--- /dev/null
+++ b/java/java-tests/testData/codeInsight/daemonCodeAnalyzer/quickFix/initializeFinalFieldInConstructor/afterIncompleteConstructor.java
@@ -0,0 +1,8 @@
+// "Initialize in constructor" "true"
+class A {
+  private final int var;
+
+    private Main() {
+        var = 0;
+    }
+}
\ No newline at end of file
diff --git a/java/java-tests/testData/codeInsight/daemonCodeAnalyzer/quickFix/initializeFinalFieldInConstructor/beforeIncompleteConstructor.java b/java/java-tests/testData/codeInsight/daemonCodeAnalyzer/quickFix/initializeFinalFieldInConstructor/beforeIncompleteConstructor.java
new file mode 100644
index 000000000000..60cc88a0ab56
--- /dev/null
+++ b/java/java-tests/testData/codeInsight/daemonCodeAnalyzer/quickFix/initializeFinalFieldInConstructor/beforeIncompleteConstructor.java
@@ -0,0 +1,6 @@
+// "Initialize in constructor" "true"
+class A {
+  private final int v<caret>ar;
+
+  private Main()
+}
\ No newline at end of file