New J2K: Add NullableQualifierConversion

2018-12-24 15:26:47 +03:00
parent 95efc5eecf
commit e232d70b52
1 changed files with 41 additions and 0 deletions
@@ -0,0 +1,41 @@
+/*
+ * Copyright 2010-2018 JetBrains s.r.o. Use of this source code is governed by the Apache 2.0 license
+ * that can be found in the license/LICENSE.txt file.
+ */
+
+package org.jetbrains.kotlin.j2k.conversions
+
+import org.jetbrains.kotlin.j2k.ConversionContext
+import org.jetbrains.kotlin.j2k.ast.Nullability
+import org.jetbrains.kotlin.j2k.bangedBangedExpr
+import org.jetbrains.kotlin.j2k.tree.*
+import org.jetbrains.kotlin.j2k.tree.impl.*
+
+class NullableQualifierConversion(private val context: ConversionContext) : RecursiveApplicableConversionBase() {
+    override fun applyToElement(element: JKTreeElement): JKTreeElement {
+        if (element !is JKQualifiedExpression) return recurse(element)
+        if (element.isSystemCall()) return recurse(element)// we don't want to have `System.err!!.println()` like expressions :)
+        if (element.receiver.type(context)?.nullability in listOf(Nullability.Nullable, Nullability.Default)
+            && element.operator == JKJavaQualifierImpl.DOT || element.operator == JKKtQualifierImpl.DOT
+        ) {
+            return recurse(
+                JKQualifiedExpressionImpl(
+                    element::receiver.detached().bangedBangedExpr(context),
+                    element.operator,
+                    element::selector.detached()
+                )
+            )
+        }
+        return recurse(element)
+    }
+
+    private fun JKQualifiedExpression.isSystemCall(): Boolean {
+        val deepestQualifiedExpression = generateSequence(this) { expression ->
+            expression.receiver as? JKQualifiedExpression
+        }.last()
+        return (deepestQualifiedExpression.receiver as? JKClassAccessExpression)
+            ?.identifier
+            ?.fqName
+            ?.startsWith("java.") == true
+    }
+}