Inline Variable: Var support

#KT-5169 Fixed

idea/src/org/jetbrains/kotlin/idea/refactoring/inline/KotlinInlineValHandler.java

@@ -54,18 +54,20 @@ import org.jetbrains.kotlin.diagnostics.Diagnostic;
 import org.jetbrains.kotlin.diagnostics.DiagnosticFactory;
 import org.jetbrains.kotlin.diagnostics.Errors;
 import org.jetbrains.kotlin.idea.JetLanguage;
-import org.jetbrains.kotlin.idea.resolve.ResolutionFacade;
 import org.jetbrains.kotlin.idea.caches.resolve.ResolutionUtils;
+import org.jetbrains.kotlin.idea.resolve.ResolutionFacade;
 import org.jetbrains.kotlin.idea.util.IdeDescriptorRenderers;
 import org.jetbrains.kotlin.idea.util.ShortenReferences;
 import org.jetbrains.kotlin.lexer.JetTokens;
 import org.jetbrains.kotlin.psi.*;
+import org.jetbrains.kotlin.psi.psiUtil.JetPsiUtilKt;
 import org.jetbrains.kotlin.resolve.BindingContext;
 import org.jetbrains.kotlin.resolve.calls.callUtil.CallUtilPackage;
 import org.jetbrains.kotlin.resolve.calls.model.ResolvedCall;
 import org.jetbrains.kotlin.resolve.lazy.BodyResolveMode;
 import org.jetbrains.kotlin.types.ErrorUtils;
 import org.jetbrains.kotlin.types.JetType;
+import org.jetbrains.kotlin.types.expressions.OperatorConventions;
 
 import java.util.List;
 import java.util.Map;
@@ -85,7 +87,7 @@ public class KotlinInlineValHandler extends InlineActionHandler {
             return false;
         }
         JetProperty property = (JetProperty) element;
-        return !property.isVar() && property.getGetter() == null && property.getReceiverTypeReference() == null;
+        return property.getGetter() == null && property.getReceiverTypeReference() == null;
     }
 
     @Override
@@ -101,9 +103,15 @@ public class KotlinInlineValHandler extends InlineActionHandler {
         final Set<PsiElement> assignments = Sets.newHashSet();
         for (JetExpression expression : referenceExpressions) {
             PsiElement parent = expression.getParent();
-            if (parent instanceof JetBinaryExpression &&
+
-                ((JetBinaryExpression) parent).getOperationToken() == JetTokens.EQ &&
+            JetBinaryExpression assignment = JetPsiUtilKt.getAssignmentByLHS(expression);
-                ((JetBinaryExpression) parent).getLeft() == expression) {
+            if (assignment != null) {
+                assignments.add(parent);
+            }
+
+            //noinspection SuspiciousMethodCalls
+            if (parent instanceof JetUnaryExpression &&
+                OperatorConventions.INCREMENT_OPERATIONS.contains(((JetUnaryExpression) parent).getOperationToken())) {
                 assignments.add(parent);
             }
         }
@@ -111,6 +119,10 @@ public class KotlinInlineValHandler extends InlineActionHandler {
         final JetExpression initializer;
         if (initializerInDeclaration != null) {
             initializer = initializerInDeclaration;
+            if (!assignments.isEmpty()) {
+                reportAmbiguousAssignment(project, editor, name, assignments);
+                return;
+            }
         }
         else {
             if (assignments.size() == 1) {
@@ -120,9 +132,7 @@ public class KotlinInlineValHandler extends InlineActionHandler {
                 initializer = null;
             }
             if (initializer == null) {
-                String key = assignments.isEmpty() ? "variable.has.no.initializer" : "variable.has.no.dominating.definition";
+                reportAmbiguousAssignment(project, editor, name, assignments);
-                String message = RefactoringBundle.getCannotRefactorMessage(RefactoringBundle.message(key, name));
-                CommonRefactoringUtil.showErrorHint(project, editor, message, RefactoringBundle.message("inline.variable.title"), HelpID.INLINE_VARIABLE);
                 return;
             }
         }
@@ -196,6 +206,23 @@ public class KotlinInlineValHandler extends InlineActionHandler {
                 null);
     }
 
+    private static void reportAmbiguousAssignment(Project project, Editor editor, String name, Set<PsiElement> assignments) {
+        String key = assignments.isEmpty() ? "variable.has.no.initializer" : "variable.has.no.dominating.definition";
+        String message = RefactoringBundle.getCannotRefactorMessage(RefactoringBundle.message(key, name));
+        showErrorHint(project, editor, message);
+    }
+
+    private static void reportWriteAccess(Project project, Editor editor, String name) {
+        String message = RefactoringBundle.getCannotRefactorMessage(
+                RefactoringBundle.message("variable.is.accessed.for.writing", name)
+        );
+        showErrorHint(project, editor, message);
+    }
+
+    private static void showErrorHint(Project project, Editor editor, String message) {
+        CommonRefactoringUtil.showErrorHint(project, editor, message, RefactoringBundle.message("inline.variable.title"), HelpID.INLINE_VARIABLE);
+    }
+
     private static void highlightExpressions(Project project, Editor editor, List<? extends PsiElement> elements) {
         if (editor == null || ApplicationManager.getApplication().isUnitTestMode()) {
             return;

idea/testData/refactoring/inline/Var.kt

@@ -1,4 +0,0 @@
-fun f() {
-    var v = 239
-    println(<caret>v)
-}

idea/testData/refactoring/inline/addParenthesis/IfIntoPostfix.kt

@@ -1,3 +1,4 @@
+// ERROR: Cannot perform refactoring.\nCannot find a single definition to inline
 fun f() {
     val v = if (true) a else b
     println(<caret>v++)

idea/testData/refactoring/inline/addParenthesis/IfIntoPostfix.kt.after

@@ -1,3 +0,0 @@
-fun f() {
-    println((if (true) a else b)++)
-}

idea/testData/refactoring/inline/varNoWrite.kt

@@ -0,0 +1,4 @@
+fun foo() {
+    var x = 1
+    val t = <caret>x + 1
+}

idea/testData/refactoring/inline/varNoWrite.kt.after

@@ -0,0 +1,3 @@
+fun foo() {
+    val t = 1 + 1
+}

idea/testData/refactoring/inline/varWithAssignment.kt

@@ -0,0 +1,6 @@
+// ERROR: Cannot perform refactoring.\nCannot find a single definition to inline
+fun foo() {
+    var x = 1
+    val t = <caret>x + 1
+    x = 2
+}

idea/testData/refactoring/inline/varWithInc.kt

@@ -0,0 +1,6 @@
+// ERROR: Cannot perform refactoring.\nCannot find a single definition to inline
+fun foo() {
+    var x = 1
+    val t = <caret>x + 1
+    x++
+}

idea/tests/org/jetbrains/kotlin/idea/refactoring/inline/InlineTestGenerated.java

@@ -101,9 +101,21 @@ public class InlineTestGenerated extends AbstractInlineTest {
         doTest(fileName);
     }
 
-    @TestMetadata("Var.kt")
+    @TestMetadata("varNoWrite.kt")
-    public void testVar() throws Exception {
+    public void testVarNoWrite() throws Exception {
-        String fileName = JetTestUtils.navigationMetadata("idea/testData/refactoring/inline/Var.kt");
+        String fileName = JetTestUtils.navigationMetadata("idea/testData/refactoring/inline/varNoWrite.kt");
+        doTest(fileName);
+    }
+
+    @TestMetadata("varWithAssignment.kt")
+    public void testVarWithAssignment() throws Exception {
+        String fileName = JetTestUtils.navigationMetadata("idea/testData/refactoring/inline/varWithAssignment.kt");
+        doTest(fileName);
+    }
+
+    @TestMetadata("varWithInc.kt")
+    public void testVarWithInc() throws Exception {
+        String fileName = JetTestUtils.navigationMetadata("idea/testData/refactoring/inline/varWithInc.kt");
         doTest(fileName);
     }