Repl: fix bug in handling multiline commands

compiler/cli/src/org/jetbrains/kotlin/cli/jvm/repl/ReplFromTerminal.java

@@ -23,6 +23,7 @@ import org.jetbrains.kotlin.cli.common.KotlinVersion;
 import org.jetbrains.kotlin.cli.jvm.repl.messages.ReplErrorLogger;
 import org.jetbrains.kotlin.cli.jvm.repl.messages.ReplSystemInWrapper;
 import org.jetbrains.kotlin.cli.jvm.repl.messages.ReplSystemOutWrapper;
+import org.jetbrains.kotlin.cli.jvm.repl.messages.UnescapeUtilsKt;
 import org.jetbrains.kotlin.cli.jvm.repl.reader.ConsoleReplCommandReader;
 import org.jetbrains.kotlin.cli.jvm.repl.reader.IdeReplCommandReader;
 import org.jetbrains.kotlin.cli.jvm.repl.reader.ReplCommandReader;
@@ -159,6 +160,8 @@ public class ReplFromTerminal {
                 return WhatNextAfterOneLine.QUIT;
             }
 
+            line = UnescapeUtilsKt.unescapeLineBreaks(line);
+
             if (line.startsWith(":") && (line.length() == 1 || line.charAt(1) != ':')) {
                 boolean notQuit = oneCommand(line.substring(1));
                 return notQuit ? WhatNextAfterOneLine.READ_LINE : WhatNextAfterOneLine.QUIT;

compiler/cli/src/org/jetbrains/kotlin/cli/jvm/repl/messages/ReplSystemInWrapper.kt

@@ -33,7 +33,7 @@ public class ReplSystemInWrapper(
     private val isAtBufferEnd: Boolean
         get() = curBytePos == inputByteArray.size()
 
-    var isReplScriptExecuting = false
+    @Volatile var isReplScriptExecuting = false
 
     override fun read(): Int {
         if (isLastByteProcessed) {
@@ -47,7 +47,7 @@ public class ReplSystemInWrapper(
         }
 
         while (isXmlIncomplete) {
-            if (isReplScriptExecuting && !isReadLineStartSent) {
+            if (!isReadLineStartSent && isReplScriptExecuting) {
                 replWriter.printlnReadLineStart()
                 isReadLineStartSent = true
             }
@@ -69,7 +69,14 @@ public class ReplSystemInWrapper(
 
     private fun parseInput(): String {
         val xmlInput = byteBuilder.toString()
-        return "${parseXml(xmlInput)}$END_LINE"
+        val unescapedXml = parseXml(xmlInput)
+
+        val resultLine = if (isReplScriptExecuting)
+            unescapeLineBreaks(unescapedXml)
+        else
+            unescapedXml
+
+        return "$resultLine$END_LINE"
     }
 
     private fun resetBufferIfNeeded() {

compiler/cli/src/org/jetbrains/kotlin/cli/jvm/repl/messages/UnescapeUtils.kt

@@ -34,5 +34,7 @@ fun parseXml(inputMessage: String): String {
     val input = docBuilder.parse(strToSource(inputMessage))
 
     val root = input.firstChild as Element
-    return StringUtil.replace(root.textContent, XML_REPLACEMENTS, SOURCE_CHARS)
+    return root.textContent
 }
+
+fun unescapeLineBreaks(s: String) = StringUtil.replace(s, XML_REPLACEMENTS, SOURCE_CHARS)