[JS AST] Add single line comment node

js/js.ast/src/org/jetbrains/kotlin/js/backend/JsToStringGenerationVisitor.java

@@ -1046,6 +1046,14 @@ public class JsToStringGenerationVisitor extends JsVisitor {
         popSourceInfo();
     }
 
+    @Override
+    public void visitSingleLineComment(@NotNull JsSingleLineComment comment) {
+        p.print("//");
+        p.print(comment.getText());
+        needSemi = false;
+        newline();
+    }
+
     @Override
     public void visitDocComment(@NotNull JsDocComment comment) {
         boolean asSingleLine = comment.getTags().size() == 1;

js/js.ast/src/org/jetbrains/kotlin/js/backend/ast/JsSingleLineComment.kt

@@ -0,0 +1,22 @@
+/*
+ * Copyright 2010-2019 JetBrains s.r.o. and Kotlin Programming Language contributors.
+ * 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.js.backend.ast
+
+class JsSingleLineComment(val text: String) : SourceInfoAwareJsNode(), JsStatement {
+    override fun accept(visitor: JsVisitor) {
+        visitor.visitSingleLineComment(this)
+    }
+
+    override fun acceptChildren(visitor: JsVisitor) {
+    }
+
+    override fun traverse(visitor: JsVisitorWithContext, ctx: JsContext<*>) {
+        visitor.visit(this, ctx)
+        visitor.endVisit(this, ctx)
+    }
+
+    override fun deepCopy() = this
+}

js/js.ast/src/org/jetbrains/kotlin/js/backend/ast/JsVisitor.kt

@@ -159,6 +159,9 @@ abstract class JsVisitor {
     open fun visitDocComment(comment: JsDocComment): Unit =
             visitElement(comment)
 
+    open fun visitSingleLineComment(comment: JsSingleLineComment): Unit =
+            visitElement(comment)
+
     protected open fun visitElement(node: JsNode) {
     }
 }

js/js.ast/src/org/jetbrains/kotlin/js/backend/ast/JsVisitorWithContext.java

@@ -207,6 +207,9 @@ public abstract class JsVisitorWithContext {
     public void endVisit(@NotNull JsVars x, @NotNull JsContext ctx) {
     }
 
+    public void endVisit(@NotNull JsSingleLineComment x, @NotNull JsContext ctx) {
+    }
+
     public void endVisit(@NotNull JsWhile x, @NotNull JsContext ctx) {
         endVisit((JsLoop) x, ctx);
     }
@@ -383,6 +386,10 @@ public abstract class JsVisitorWithContext {
         return visit((JsLoop) x, ctx);
     }
 
+    public boolean visit(@NotNull JsSingleLineComment x, @NotNull JsContext ctx) {
+        return true;
+    }
+
     protected abstract  <T extends JsNode> T doAccept(T node);
 
     protected abstract JsExpression doAcceptLvalue(JsExpression expr);