More readable rule language for indent position calculation

2026-09-27 10:03:11 +07:00 · 2016-05-20 16:46:18 +03:00
parent 8e52a6ba25
commit 463adf8de2
2 changed files with 94 additions and 30 deletions
@@ -19,12 +19,9 @@ import com.intellij.formatting.Indent;
 import com.intellij.lang.Language;
 import com.intellij.openapi.editor.Editor;
 import com.intellij.openapi.editor.ex.EditorEx;
-import com.intellij.openapi.editor.highlighter.EditorHighlighter;
-import com.intellij.openapi.editor.highlighter.HighlighterIterator;
 import com.intellij.openapi.project.Project;
 import com.intellij.psi.PsiFile;
 import com.intellij.psi.tree.IElementType;
-import com.intellij.util.text.CharArrayUtil;
 import org.jetbrains.annotations.NotNull;
 import org.jetbrains.annotations.Nullable;

@@ -33,6 +30,14 @@ import org.jetbrains.annotations.Nullable;
 * the indentation, it forwards the request to FormatterBasedLineIndentProvider.
 */
 public abstract class JavaLikeLangLineIndentProvider extends FormatterBasedLineIndentProvider {
+  
+  protected enum JavaLikeElement implements SemanticEditorPosition.SyntaxElement {
+    Whitespace,
+    Semicolon,
+    BlockClosingBrace
+  }
+  
+  
  @Nullable
  @Override
  public String getLineIndent(@NotNull Project project, @NotNull Editor editor, int offset) {
@@ -54,39 +59,34 @@ public abstract class JavaLikeLangLineIndentProvider extends FormatterBasedLineI
  @Nullable
  protected Indent.Type getIndent(@NotNull Editor editor, int offset) {
    if (offset > 0) {
-      CharSequence docChars = editor.getDocument().getCharsSequence();
-      EditorHighlighter highlighter = ((EditorEx)editor).getHighlighter();
-      HighlighterIterator iterator = highlighter.createIterator(offset - 1);
-      if (isWhitespace(iterator.getTokenType())) {
-        if (containsLineBreaks(iterator, docChars)) {
-          iterator.retreat();
-          if (!iterator.atEnd()) {
-            if (isEndOfCodeBlock(iterator)) return Indent.Type.NONE;
-          }
-        }
+      if (matchesRule(editor, offset - 1,
+                 position -> position.isAt(JavaLikeElement.Whitespace) &&
+                            position.isAtMultiline()
+                            && position
+                              .before()
+                              .beforeOptional(JavaLikeElement.Semicolon)
+                              .beforeOptional(JavaLikeElement.Whitespace)
+                              .isAt(JavaLikeElement.BlockClosingBrace)
+      )) {
+        return Indent.Type.NONE;
      }
    }
    return null;
  }
-  
-  protected abstract boolean isWhitespace(@NotNull IElementType tokenType);
-  
-  private static boolean containsLineBreaks(@NotNull HighlighterIterator iterator, @NotNull CharSequence chars) {
-    return CharArrayUtil.containLineBreaks(chars, iterator.getStart(), iterator.getEnd());
-  }
-  
-  protected boolean isEndOfCodeBlock(@NotNull HighlighterIterator iterator) {
-    if (isSemicolon(iterator.getTokenType())) iterator.retreat();
-    if (!iterator.atEnd()) {
-      if (isWhitespace(iterator.getTokenType())) iterator.retreat();
-      if (!iterator.atEnd()) {
-        return isBlockClosingBrace(iterator.getTokenType());
+
+  private boolean matchesRule(@NotNull Editor editor, int offset, @NotNull Rule rule) {
+    SemanticEditorPosition editorPosition = new SemanticEditorPosition((EditorEx)editor, offset) {
+      @Override
+      public SyntaxElement map(@NotNull IElementType elementType) {
+        return mapType(elementType);
      }
-    }
-    return false;
+    };
+    return rule.check(editorPosition);
  }
  
-  protected abstract boolean isSemicolon(@NotNull IElementType tokenType);
+  protected abstract SemanticEditorPosition.SyntaxElement mapType(@NotNull IElementType tokenType);
  
-  protected abstract boolean isBlockClosingBrace(@NotNull IElementType tokenType);
+  private interface Rule {
+    boolean check(SemanticEditorPosition wrapper);
+  }
 }
@@ -0,0 +1,64 @@
+/*
+ * Copyright 2000-2016 JetBrains s.r.o.
+ *
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ * http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+package com.intellij.psi.impl.source.codeStyle;
+
+import com.intellij.openapi.editor.ex.EditorEx;
+import com.intellij.openapi.editor.highlighter.HighlighterIterator;
+import com.intellij.psi.tree.IElementType;
+import com.intellij.util.text.CharArrayUtil;
+import org.jetbrains.annotations.NotNull;
+
+/**
+ * @author Rustam Vishnyakov
+ */
+public abstract class SemanticEditorPosition {
+  public interface SyntaxElement {}
+  
+  private final HighlighterIterator myIterator;
+  private final CharSequence myChars;
+
+  public SemanticEditorPosition(@NotNull EditorEx editor, int offset) {
+    myChars = editor.getDocument().getCharsSequence();
+    myIterator = editor.getHighlighter().createIterator(offset);
+  }
+  
+  public SemanticEditorPosition beforeOptional(@NotNull SyntaxElement syntaxElement) {
+    if (!myIterator.atEnd()) {
+      if (syntaxElement.equals(map(myIterator.getTokenType()))) myIterator.retreat();
+    }
+    return this;
+  }
+  
+  public boolean isAtMultiline() {
+    if (!myIterator.atEnd()) {
+      return CharArrayUtil.containLineBreaks(myChars, myIterator.getStart(), myIterator.getEnd());
+    }
+    return false;
+  }
+  
+  public SemanticEditorPosition before() {
+    if (!myIterator.atEnd()) {
+      myIterator.retreat();
+    }
+    return this;
+  }
+  
+  public boolean isAt(@NotNull SyntaxElement syntaxElement) {
+    return !myIterator.atEnd() && syntaxElement.equals(map(myIterator.getTokenType()));
+  }
+  
+  public abstract SyntaxElement map(@NotNull IElementType elementType); 
+}