[javadoc] IDEA-285556 Support language injection into snippet

Add a enter handler for snippets to insert leading asterisks if needed.

Signed-off-by: Nikita Eshkeev <nikita.eshkeev@jetbrains.com>

GitOrigin-RevId: 365eaf0c873f11673dd03cbbb7b4395410e0e110

java/java-impl/src/META-INF/JavaPlugin.xml

@@ -977,6 +977,7 @@
     <testFinder implementation="com.intellij.testIntegration.JavaTestFinder"/>
     <filePasteProvider implementation="com.intellij.ide.JavaFilePasteProvider" order="before fileList"/>
     <enterHandlerDelegate implementation="com.intellij.javadoc.EnterInJavadocParamDescriptionHandler"/>
+    <enterHandlerDelegate implementation="com.intellij.javadoc.JavadocSnippetEnterHandler"/>
     <editorNavigation implementation="com.intellij.javadoc.JavadocNavigationDelegate"/>
     <methodNavigationOffsetProvider implementation="com.intellij.codeInsight.navigation.JavaMethodNavigationOffsetProvider"/>
     <dom.customAnnotationChecker implementation="com.intellij.util.xml.impl.ExtendsClassChecker"/>

java/java-impl/src/com/intellij/javadoc/JavadocSnippetEnterHandler.java

@@ -0,0 +1,69 @@
+// Copyright 2000-2021 JetBrains s.r.o. and contributors. Use of this source code is governed by the Apache 2.0 license.
+package com.intellij.javadoc;
+
+import com.intellij.application.options.CodeStyle;
+import com.intellij.codeInsight.editorActions.enter.EnterHandlerDelegateAdapter;
+import com.intellij.lang.injection.InjectedLanguageManager;
+import com.intellij.openapi.actionSystem.DataContext;
+import com.intellij.openapi.editor.CaretModel;
+import com.intellij.openapi.editor.Document;
+import com.intellij.openapi.editor.Editor;
+import com.intellij.openapi.editor.EditorModificationUtilEx;
+import com.intellij.psi.PsiElement;
+import com.intellij.psi.PsiFile;
+import com.intellij.psi.PsiJavaFile;
+import com.intellij.psi.codeStyle.JavaCodeStyleSettings;
+import com.intellij.psi.javadoc.PsiSnippetDocTag;
+import com.intellij.util.DocumentUtil;
+import com.intellij.util.ObjectUtils;
+import org.jetbrains.annotations.NotNull;
+
+public class JavadocSnippetEnterHandler extends EnterHandlerDelegateAdapter {
+
+  @Override
+  public Result postProcessEnter(@NotNull PsiFile file,
+                                 @NotNull Editor editor,
+                                 @NotNull DataContext dataContext) {
+    if (!(file instanceof PsiJavaFile) || !file.isValid()) return Result.Continue;
+
+    final CaretModel caretModel = editor.getCaretModel();
+    int caretOffset = caretModel.getOffset();
+
+    final PsiElement current = file.findElementAt(caretOffset);
+    if (current == null) return Result.Continue;
+
+    final InjectedLanguageManager injectedLanguageManager = InjectedLanguageManager.getInstance(file.getProject());
+    final PsiSnippetDocTag host = ObjectUtils.tryCast(injectedLanguageManager.getInjectionHost(current), PsiSnippetDocTag.class);
+    if (host == null) return Result.Continue;
+
+    final Document document = editor.getDocument();
+    final String prefix = calcPrefix(host);
+
+    final int lineStartOffset = DocumentUtil.getLineStartOffset(caretOffset, document);
+    document.insertString(lineStartOffset, prefix);
+
+    caretModel.moveToOffset(caretOffset + prefix.length());
+    EditorModificationUtilEx.scrollToCaret(editor);
+
+    return Result.Continue;
+  }
+
+  private static String calcPrefix(PsiSnippetDocTag host) {
+    final PsiFile file = host.getContainingFile();
+    final String text = file.getText();
+
+    int offset = host.getTextOffset();
+    int asteriskOffset = offset;
+    while (text.charAt(offset) != '\n' && offset > 0) {
+      if (text.charAt(offset) == '*') asteriskOffset = offset;
+      offset --;
+    }
+
+    final String prefix = text.substring(offset + 1, asteriskOffset);
+
+    final JavaCodeStyleSettings settings = CodeStyle.getCustomSettings(file, JavaCodeStyleSettings.class);
+
+    return settings.JD_LEADING_ASTERISKS_ARE_ENABLED ? prefix + "*" : prefix;
+  }
+
+}

java/java-tests/testData/codeInsight/javadoc/snippet/enterhandler/afterEnterAfterClosingBracket.java

@@ -0,0 +1,16 @@
+// "_ignore" "true"
+
+class Main {
+  /**
+   * A simple program.
+   * {@snippet :
+   * class HelloWorld {
+   *   void f() {
+   *     System.out.println();
+   *   }
+   *   void g() {}
+   * }
+   * }
+   */
+  void f() {}
+}

java/java-tests/testData/codeInsight/javadoc/snippet/enterhandler/afterEnterInMethodBody.java

@@ -0,0 +1,16 @@
+// "_ignore" "true"
+
+class Main {
+  /**
+   * A simple program.
+   * {@snippet :
+   * class HelloWorld {
+   *   void f() {
+   *     System.out.println();
+   *   <caret>
+   *   }
+   * }
+   * }
+   */
+  void f() {}
+}

java/java-tests/testData/codeInsight/javadoc/snippet/enterhandler/afterEnterInMethodJavadoc.java

@@ -0,0 +1,13 @@
+// "_ignore" "true"
+
+class Main {
+  /**
+   * A simple program.
+   * {@snippet :
+   * class HelloWorld {
+   *    <caret>
+   * }
+   * }
+   */
+  void f() {}
+}

java/java-tests/testData/codeInsight/javadoc/snippet/enterhandler/afterEnterInTopLevelClassJavadoc.java

@@ -0,0 +1,14 @@
+// "_ignore" "true"
+
+/**
+ * A simple program.
+ * {@snippet :
+ * class HelloWorld {
+ *     public void f() {
+ *     <caret>
+ * }
+ * }
+ * }
+ */
+class Main {
+}

java/java-tests/testData/codeInsight/javadoc/snippet/enterhandler/beforeEnterAfterClosingBracket.java

@@ -0,0 +1,15 @@
+// "_ignore" "true"
+
+class Main {
+  /**
+   * A simple program.
+   * {@snippet :
+   * class HelloWorld {
+   *   void f() {
+   *     System.out.println();
+   *   }<caret>void g() {}
+   * }
+   * }
+   */
+  void f() {}
+}

java/java-tests/testData/codeInsight/javadoc/snippet/enterhandler/beforeEnterInMethodBody.java

@@ -0,0 +1,15 @@
+// "_ignore" "true"
+
+class Main {
+  /**
+   * A simple program.
+   * {@snippet :
+   * class HelloWorld {
+   *   void f() {
+   *     System.out.println();<caret>
+   *   }
+   * }
+   * }
+   */
+  void f() {}
+}

java/java-tests/testData/codeInsight/javadoc/snippet/enterhandler/beforeEnterInMethodJavadoc.java

@@ -0,0 +1,11 @@
+// "_ignore" "true"
+
+class Main {
+  /**
+   * A simple program.
+   * {@snippet :
+   * class HelloWorld {<caret>}
+   * }
+   */
+  void f() {}
+}

java/java-tests/testData/codeInsight/javadoc/snippet/enterhandler/beforeEnterInTopLevelClassJavadoc.java

@@ -0,0 +1,12 @@
+// "_ignore" "true"
+
+/**
+ * A simple program.
+ * {@snippet :
+ * class HelloWorld {
+ *     public void f() {<caret>}
+ * }
+ * }
+ */
+class Main {
+}

java/java-tests/testSrc/com/intellij/java/codeInsight/javadoc/JavadocSnippetEnterHandlerTest.java

@@ -0,0 +1,25 @@
+// Copyright 2000-2021 JetBrains s.r.o. and contributors. Use of this source code is governed by the Apache 2.0 license.
+package com.intellij.java.codeInsight.javadoc;
+
+import com.intellij.codeInsight.daemon.quickFix.ActionHint;
+import com.intellij.codeInsight.daemon.quickFix.LightQuickFixParameterizedTestCase;
+import org.jetbrains.annotations.NotNull;
+
+public class JavadocSnippetEnterHandlerTest extends LightQuickFixParameterizedTestCase {
+  @Override
+  protected String getBasePath() {
+    return "/codeInsight/javadoc/snippet/enterhandler";
+  }
+
+  @Override
+  protected void doAction(@NotNull ActionHint actionHint, @NotNull String testFullPath, @NotNull String testName) {
+    executeAction("EditorEnter");
+
+    checkResult(testName);
+  }
+
+  private void checkResult(@NotNull final String testName) {
+    final String expectedFilePath = getBasePath() + "/after" + testName;
+    checkResultByFile("In file: " + expectedFilePath, expectedFilePath, false);
+  }
+}

platform/lang-impl/src/com/intellij/codeInsight/editorActions/enter/EnterBetweenBracesFinalHandler.java

@@ -6,13 +6,17 @@ import com.intellij.codeInsight.CodeInsightSettings;
 import com.intellij.codeInsight.editorActions.CodeDocumentationUtil;
 import com.intellij.codeInsight.editorActions.EnterHandler;
 import com.intellij.lang.Language;
+import com.intellij.lang.injection.InjectedLanguageManager;
 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.project.Project;
 import com.intellij.openapi.util.Ref;
+import com.intellij.psi.PsiDocumentManager;
+import com.intellij.psi.PsiElement;
 import com.intellij.psi.PsiFile;
+import com.intellij.psi.PsiLanguageInjectionHost;
 import com.intellij.psi.codeStyle.CodeStyleManager;
 import com.intellij.util.text.CharArrayUtil;
 import org.jetbrains.annotations.NotNull;
@@ -33,7 +37,6 @@ public class EnterBetweenBracesFinalHandler extends EnterHandlerDelegateAdapter
     if (!CodeInsightSettings.getInstance().SMART_INDENT_ON_ENTER) {
       return Result.Continue;
     }
-
     Document document = editor.getDocument();
     CharSequence text = document.getCharsSequence();
     int caretOffset = caretOffsetRef.get().intValue();
@@ -43,29 +46,76 @@ public class EnterBetweenBracesFinalHandler extends EnterHandlerDelegateAdapter
       return Result.Continue;
     }
 
-    final int line = document.getLineNumber(caretOffset);
-    final int start = document.getLineStartOffset(line);
-    final CodeDocumentationUtil.CommentContext commentContext =
-      CodeDocumentationUtil.tryParseCommentContext(file, text, caretOffset, start);
-
-    // special case: enter inside "()" or "{}"
-    String indentInsideJavadoc = helper.isInComment(file, editor, caretOffset) && commentContext.docAsterisk
-                                 ? CodeDocumentationUtil.getIndentInsideJavadoc(document, caretOffset)
-                                 : null;
+    final Data data = new Data(file, document, caretOffset);
+    final String indentInsideJavadoc = data.getIndentInsideJavadoc(helper, editor);
 
     originalHandler.execute(editor, editor.getCaretModel().getCurrentCaret(), dataContext);
 
     Project project = editor.getProject();
     if (indentInsideJavadoc != null &&
         project != null &&
-        CodeStyleManager.getInstance(project).getDocCommentSettings(file).isLeadingAsteriskEnabled()) {
-      document.insertString(editor.getCaretModel().getOffset(), "*" + indentInsideJavadoc);
+        data.isLeadingAsteriskEnabled()) {
+      editor.getDocument().insertString(editor.getCaretModel().getOffset(), "*" + indentInsideJavadoc);
     }
 
     helper.formatAtOffset(file, editor, editor.getCaretModel().getOffset(), EnterHandler.getLanguage(dataContext));
     return indentInsideJavadoc == null ? Result.Continue : Result.DefaultForceIndent;
   }
 
+  private static final class Data {
+    private final @NotNull PsiFile myFile;
+    private final @NotNull Document myDocument;
+    private final @NotNull CharSequence myText;
+    private final int myOffset;
+
+    private Data(@NotNull PsiFile file,
+                 @NotNull Document document,
+                 int offset) {
+      final PsiElement element = file.findElementAt(offset);
+
+      if (element != null) {
+        final PsiLanguageInjectionHost injectionHost = InjectedLanguageManager.getInstance(file.getProject()).getInjectionHost(element);
+        if (injectionHost != null) {
+          final PsiDocumentManager documentManager = PsiDocumentManager.getInstance(element.getProject());
+          final Document hostDocument = documentManager.getDocument(injectionHost.getContainingFile());
+          if (hostDocument != null) {
+            myDocument = hostDocument;
+            myText = hostDocument.getCharsSequence();
+            myFile = injectionHost.getContainingFile();
+            myOffset = injectionHost.getTextOffset();
+            return;
+          }
+        }
+      }
+
+      myFile = file;
+      myDocument = document;
+      myText = document.getText();
+      myOffset = offset;
+    }
+
+    public @Nullable String getIndentInsideJavadoc(EnterBetweenBracesDelegate helper, Editor editor) {
+      final CodeDocumentationUtil.CommentContext commentContext = getCommentContext();
+      return isInComment(helper, editor) && commentContext.docAsterisk
+             ? CodeDocumentationUtil.getIndentInsideJavadoc(myDocument, myOffset)
+             : null;
+    }
+
+    private @NotNull CodeDocumentationUtil.CommentContext getCommentContext() {
+      final int line = myDocument.getLineNumber(myOffset);
+      final int start = myDocument.getLineStartOffset(line);
+      return CodeDocumentationUtil.tryParseCommentContext(myFile, myText, myOffset, start);
+    }
+
+    private boolean isInComment(final EnterBetweenBracesDelegate helper, Editor editor) {
+      return helper.isInComment(myFile, editor, myOffset);
+    }
+
+    private boolean isLeadingAsteriskEnabled() {
+      return CodeStyleManager.getInstance(myFile.getProject()).getDocCommentSettings(myFile).isLeadingAsteriskEnabled();
+    }
+  }
+
   protected boolean isApplicable(@NotNull PsiFile file,
                                  @NotNull Editor editor,
                                  CharSequence documentText,
@@ -79,8 +129,7 @@ public class EnterBetweenBracesFinalHandler extends EnterHandlerDelegateAdapter
            !helper.bracesAreInTheSameElement(file, editor, prevCharOffset, nextCharOffset);
   }
 
-  @NotNull
-  protected EnterBetweenBracesDelegate getLanguageImplementation(@Nullable Language language) {
+  protected static @NotNull EnterBetweenBracesDelegate getLanguageImplementation(@Nullable Language language) {
     if (language != null) {
       final EnterBetweenBracesDelegate helper = EnterBetweenBracesDelegate.EP_NAME.forLanguage(language);
       if (helper != null) {