New J2K: convert Java method reference to Kotlin one on copy-pasting Java code

#KT-34965 fixed

nj2k/src/org/jetbrains/kotlin/nj2k/JavaToJKTreeBuilder.kt

@@ -470,6 +470,7 @@ class JavaToJKTreeBuilder constructor(
                 is JKClassSymbol -> JKClassAccessExpression(symbol)
                 is JKFieldSymbol -> JKFieldAccessExpression(symbol)
                 is JKPackageSymbol -> JKPackageAccessExpression(symbol)
+                is JKMethodSymbol -> JKMethodAccessExpression(symbol)
                 else -> throwCanNotConvertError("unexpected symbol ${symbol::class}")
             }.qualified(qualifierExpression?.toJK()).also {
                 it.withFormattingFrom(this)

nj2k/src/org/jetbrains/kotlin/nj2k/conversions/BuiltinMembersConversion.kt

@@ -68,6 +68,14 @@ class BuiltinMembersConversion(context: NewJ2kConverterContext) : RecursiveAppli
                 true
             }
 
+        is JKMethodAccessExpression ->
+            conversions[identifier.deepestFqName()]?.firstOrNull { conversion ->
+                if (conversion.from !is Method) return@firstOrNull false
+                if (conversion.to !is Method) return@firstOrNull false
+                if (conversion.filter?.invoke(this) == false) return@firstOrNull false
+                true
+            }
+
         is JKNewExpression ->
             conversions[classSymbol.deepestFqName()]?.firstOrNull { conversion ->
                 if (conversion.from !is NewExpression) return@firstOrNull false
@@ -93,21 +101,23 @@ class BuiltinMembersConversion(context: NewJ2kConverterContext) : RecursiveAppli
                         symbolProvider.provideMethodSymbol(fqName),
                         argumentsProvider(from::arguments.detached()),
                         from::typeArgumentList.detached()
-                    ).withFormattingFrom(from)
+                    )
                 is JKFieldAccessExpression ->
                     JKCallExpressionImpl(
                         symbolProvider.provideMethodSymbol(fqName),
                         JKArgumentList(),
                         JKTypeArgumentList()
-                    ).withFormattingFrom(from)
+                    )
+                is JKMethodAccessExpression ->
+                    JKMethodAccessExpression(symbolProvider.provideMethodSymbol(fqName))
                 is JKNewExpression ->
                     JKCallExpressionImpl(
                         symbolProvider.provideMethodSymbol(fqName),
                         argumentsProvider(from::arguments.detached()),
                         JKTypeArgumentList()
-                    ).withFormattingFrom(from)
+                    )
                 else -> error("Bad conversion")
-            }
+            }.withFormattingFrom(from)
     }
 
     private inner class FieldBuilder(

nj2k/src/org/jetbrains/kotlin/nj2k/printing/JKCodeBuilder.kt

@@ -142,6 +142,10 @@ internal class JKCodeBuilder(context: NewJ2kConverterContext) {
             printer.renderSymbol(classAccessExpression.identifier, classAccessExpression)
         }
 
+        override fun visitMethodAccessExpression(methodAccessExpression: JKMethodAccessExpression) {
+            printer.renderSymbol(methodAccessExpression.identifier, methodAccessExpression)
+        }
+
         override fun visitFileRaw(file: JKFile) {
             if (file.packageDeclaration.name.value.isNotEmpty()) {
                 file.packageDeclaration.accept(this)

nj2k/src/org/jetbrains/kotlin/nj2k/tree/expressions.kt

@@ -181,7 +181,7 @@ class JKNewExpression(
 
 
 class JKFieldAccessExpression(var identifier: JKFieldSymbol) : JKExpression() {
-    override fun calculateType(typeFactory: JKTypeFactory) = identifier.fieldType 
+    override fun calculateType(typeFactory: JKTypeFactory) = identifier.fieldType
     override fun accept(visitor: JKVisitor) = visitor.visitFieldAccessExpression(this)
 }
 
@@ -196,6 +196,11 @@ class JKClassAccessExpression(var identifier: JKClassSymbol) : JKExpression() {
     override fun accept(visitor: JKVisitor) = visitor.visitClassAccessExpression(this)
 }
 
+class JKMethodAccessExpression(val identifier: JKMethodSymbol) : JKExpression() {
+    override fun calculateType(typeFactory: JKTypeFactory): JKType? = null
+    override fun accept(visitor: JKVisitor) = visitor.visitMethodAccessExpression(this)
+}
+
 class JKMethodReferenceExpression(
     qualifier: JKExpression,
     val identifier: JKSymbol,

nj2k/src/org/jetbrains/kotlin/nj2k/tree/visitors/JKVisitor.kt

@@ -83,6 +83,7 @@ abstract class JKVisitor {
     open fun visitFieldAccessExpression(fieldAccessExpression: JKFieldAccessExpression) = visitExpression(fieldAccessExpression)
     open fun visitPackageAccessExpression(packageAccessExpression: JKPackageAccessExpression) = visitExpression(packageAccessExpression)
     open fun visitClassAccessExpression(classAccessExpression: JKClassAccessExpression) = visitExpression(classAccessExpression)
+    open fun visitMethodAccessExpression(methodAccessExpression: JKMethodAccessExpression) = visitExpression(methodAccessExpression)
     open fun visitMethodReferenceExpression(methodReferenceExpression: JKMethodReferenceExpression) =
         visitExpression(methodReferenceExpression)
 

nj2k/src/org/jetbrains/kotlin/nj2k/tree/visitors/JKVisitorWithCommentsPrinting.kt

@@ -579,6 +579,14 @@ abstract class JKVisitorWithCommentsPrinting : JKVisitor() {
     open fun visitPackageAccessExpressionRaw(packageAccessExpression: JKPackageAccessExpression) =
         visitExpressionRaw(packageAccessExpression)
 
+    override fun visitMethodAccessExpression(methodAccessExpression: JKMethodAccessExpression) {
+        printLeftNonCodeElements(methodAccessExpression)
+        visitMethodAccessExpressionRaw(methodAccessExpression)
+        printRightNonCodeElements(methodAccessExpression)
+    }
+
+    open fun visitMethodAccessExpressionRaw(methodAccessExpression: JKMethodAccessExpression) = visitExpressionRaw(methodAccessExpression)
+
     override fun visitClassAccessExpression(classAccessExpression: JKClassAccessExpression) {
         printLeftNonCodeElements(classAccessExpression)
         visitClassAccessExpressionRaw(classAccessExpression)

nj2k/testData/copyPaste/ConvertedMethodReference.expected.kt

@@ -0,0 +1,3 @@
+fun foo() {
+    println
+}

nj2k/testData/copyPaste/ConvertedMethodReference.java

@@ -0,0 +1,5 @@
+class A {
+    public static void main(String[] args) {
+        <selection>System.out.println</selection>("nya")
+    }
+}

nj2k/testData/copyPaste/ConvertedMethodReference.to.kt

@@ -0,0 +1,3 @@
+fun foo() {
+    <caret>
+}

nj2k/testData/copyPaste/UnconvertedMethodReference.expected.kt

@@ -0,0 +1,3 @@
+fun foo() {
+    System.out.printf
+}

nj2k/testData/copyPaste/UnconvertedMethodReference.java

@@ -0,0 +1,5 @@
+class A {
+    public static void main(String[] args) {
+        <selection>System.out.printf</selection>("nya")
+    }
+}

nj2k/testData/copyPaste/UnconvertedMethodReference.to.kt

@@ -0,0 +1,3 @@
+fun foo() {
+    <caret>
+}

nj2k/tests/org/jetbrains/kotlin/nj2k/NewJavaToKotlinCopyPasteConversionTestGenerated.java

@@ -83,6 +83,11 @@ public class NewJavaToKotlinCopyPasteConversionTestGenerated extends AbstractNew
         runTest("nj2k/testData/copyPaste/ConversionInCorrectContext.java");
     }
 
+    @TestMetadata("ConvertedMethodReference.java")
+    public void testConvertedMethodReference() throws Exception {
+        runTest("nj2k/testData/copyPaste/ConvertedMethodReference.java");
+    }
+
     @TestMetadata("CopyAnnotation.java")
     public void testCopyAnnotation() throws Exception {
         runTest("nj2k/testData/copyPaste/CopyAnnotation.java");
@@ -222,4 +227,9 @@ public class NewJavaToKotlinCopyPasteConversionTestGenerated extends AbstractNew
     public void testSingleWordFromIdentifier() throws Exception {
         runTest("nj2k/testData/copyPaste/SingleWordFromIdentifier.java");
     }
+
+    @TestMetadata("UnconvertedMethodReference.java")
+    public void testUnconvertedMethodReference() throws Exception {
+        runTest("nj2k/testData/copyPaste/UnconvertedMethodReference.java");
+    }
 }