Make auto-indent work for multiline string with injection (KT-17942)

#KT-17942 Fixed

idea/src/org/jetbrains/kotlin/idea/editor/KotlinMultilineStringEnterHandler.kt

@@ -20,10 +20,12 @@ import com.intellij.codeInsight.CodeInsightSettings
 import com.intellij.codeInsight.editorActions.enter.EnterHandlerDelegate
 import com.intellij.codeInsight.editorActions.enter.EnterHandlerDelegate.Result
 import com.intellij.codeInsight.editorActions.enter.EnterHandlerDelegateAdapter
+import com.intellij.injected.editor.EditorWindow
 import com.intellij.openapi.actionSystem.DataContext
 import com.intellij.openapi.editor.Document
 import com.intellij.openapi.editor.Editor
 import com.intellij.openapi.editor.actionSystem.EditorActionHandler
+import com.intellij.openapi.editor.ex.EditorEx
 import com.intellij.openapi.project.Project
 import com.intellij.openapi.util.Ref
 import com.intellij.openapi.util.TextRange
@@ -34,6 +36,9 @@ import com.intellij.psi.PsiFile
 import com.intellij.psi.codeStyle.CodeStyleSettingsManager
 import com.intellij.psi.impl.source.tree.LeafPsiElement
 import org.jetbrains.kotlin.idea.KotlinFileType
+import org.jetbrains.kotlin.idea.refactoring.hostEditor
+import org.jetbrains.kotlin.idea.refactoring.project
+import org.jetbrains.kotlin.idea.refactoring.toPsiFile
 import org.jetbrains.kotlin.idea.util.application.runWriteAction
 import org.jetbrains.kotlin.lexer.KtTokens
 import org.jetbrains.kotlin.psi.*
@@ -50,11 +55,25 @@ class KotlinMultilineStringEnterHandler : EnterHandlerDelegateAdapter() {
     override fun preprocessEnter(
             file: PsiFile, editor: Editor, caretOffset: Ref<Int>, caretAdvance: Ref<Int>, dataContext: DataContext,
             originalHandler: EditorActionHandler?): EnterHandlerDelegate.Result {
+        val offset = caretOffset.get().toInt()
+        if (editor !is EditorWindow) {
+            return preprocessEnter(file, editor, offset, originalHandler, dataContext)
+        }
+
+        val hostPosition = getHostPosition(dataContext) ?: return Result.Continue
+        return preprocessEnter(hostPosition, originalHandler, dataContext)
+    }
+
+    private fun preprocessEnter(hostPosition: HostPosition, originalHandler: EditorActionHandler?, dataContext: DataContext): Result {
+        val (file, editor, offset) = hostPosition
+        return preprocessEnter(file, editor, offset, originalHandler, dataContext)
+    }
+
+    private fun preprocessEnter(file: PsiFile, editor: Editor, offset: Int, originalHandler: EditorActionHandler?, dataContext: DataContext): Result {
         if (file !is KtFile) return Result.Continue
 
         val document = editor.document
         val text = document.text
-        val offset = caretOffset.get().toInt()
 
         if (offset == 0 || offset >= text.length) return Result.Continue
 
@@ -81,6 +100,15 @@ class KotlinMultilineStringEnterHandler : EnterHandlerDelegateAdapter() {
     }
 
     override fun postProcessEnter(file: PsiFile, editor: Editor, dataContext: DataContext): Result {
+        if (editor !is EditorWindow) {
+            return postProcessEnter(file, editor)
+        }
+
+        val hostPosition = getHostPosition(dataContext) ?: return Result.Continue
+        return postProcessEnter(hostPosition.file, hostPosition.editor)
+    }
+
+    private fun postProcessEnter(file: PsiFile, editor: Editor): Result {
         if (file !is KtFile) return Result.Continue
 
         if (!wasInMultilineString) return Result.Continue
@@ -344,5 +372,16 @@ class KotlinMultilineStringEnterHandler : EnterHandlerDelegateAdapter() {
                         })
             }
         }
+
+        private data class HostPosition(val file: PsiFile, val editor: Editor, val offset: Int)
+        private fun getHostPosition(dataContext: DataContext): HostPosition? {
+            val editor = dataContext.hostEditor as? EditorEx ?: return null
+            val project = dataContext.project
+
+            val virtualFile = editor.virtualFile ?: return null
+            val psiFile = virtualFile.toPsiFile(project) ?: return null
+
+            return HostPosition(psiFile, editor, editor.caretModel.offset)
+        }
     }
 }

idea/src/org/jetbrains/kotlin/idea/refactoring/dataContextUtils.kt

@@ -18,7 +18,11 @@ package org.jetbrains.kotlin.idea.refactoring
 
 import com.intellij.openapi.actionSystem.CommonDataKeys
 import com.intellij.openapi.actionSystem.DataContext
+import com.intellij.openapi.editor.Editor
 import com.intellij.openapi.project.Project
 
 val DataContext.project: Project
     get() = CommonDataKeys.PROJECT.getData(this)!!
+
+val DataContext.hostEditor: Editor?
+    get() = CommonDataKeys.HOST_EDITOR.getData(this)

idea/testData/editor/enterHandler/multilineString/spaces/enterInInjectedFragment.kt

@@ -0,0 +1,12 @@
+// language=HTML
+val a =
+        """
+        <html><caret>
+        </html>"""
+//-----
+// language=HTML
+val a =
+        """
+        <html>
+        <caret>
+        </html>"""

idea/tests/org/jetbrains/kotlin/idea/editor/AbstractMultiLineStringIndentTest.kt

@@ -38,6 +38,7 @@ abstract class AbstractMultiLineStringIndentTest : KotlinLightCodeInsightFixture
             val beforeFile = multiFileText.substringBefore(FILE_SEPARATOR).trim()
             val afterFile = multiFileText.substringAfter(FILE_SEPARATOR).trim()
 
+            myFixture.setCaresAboutInjection(false)
             myFixture.configureByText(KotlinFileType.INSTANCE, beforeFile)
             myFixture.type('\n')
 

idea/tests/org/jetbrains/kotlin/idea/editor/MultiLineStringIndentTestGenerated.java

@@ -116,6 +116,12 @@ public class MultiLineStringIndentTestGenerated extends AbstractMultiLineStringI
             doTest(fileName);
         }
 
+        @TestMetadata("enterInInjectedFragment.kt")
+        public void testEnterInInjectedFragment() throws Exception {
+            String fileName = KotlinTestUtils.navigationMetadata("idea/testData/editor/enterHandler/multilineString/spaces/enterInInjectedFragment.kt");
+            doTest(fileName);
+        }
+
         @TestMetadata("enterInLineWithMarginOnNotMargedLine.kt")
         public void testEnterInLineWithMarginOnNotMargedLine() throws Exception {
             String fileName = KotlinTestUtils.navigationMetadata("idea/testData/editor/enterHandler/multilineString/spaces/enterInLineWithMarginOnNotMargedLine.kt");