platform/platform-tests/testSrc/com/intellij/codeInsight/folding/impl/CompositeFoldingBuilderTest.java

/*
 * Copyright 2000-2014 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.codeInsight.folding.impl;

import com.intellij.lang.ASTNode;
import com.intellij.lang.folding.*;
import com.intellij.openapi.editor.Document;
import com.intellij.openapi.editor.impl.AbstractEditorTest;
import com.intellij.openapi.fileTypes.PlainTextLanguage;
import com.intellij.openapi.util.TextRange;
import com.intellij.psi.PsiElement;
import com.intellij.testFramework.TestFileType;
import org.jetbrains.annotations.NotNull;

import java.util.Collection;
import java.util.List;

import static com.intellij.testFramework.PlatformTestCase.initPlatformLangPrefix;

public class CompositeFoldingBuilderTest extends AbstractEditorTest {
  static {
    initPlatformLangPrefix();
  }

  @Override
  protected void setUp() throws Exception {
    super.setUp();
    init("Some plain text to fold", TestFileType.TEXT);
  }

  public void testAllowOnlyOneDescriptorPerTextRange() {
    final FoldingBuilder first = createDummyFoldingBuilder("plain", "mountain");
    final FoldingBuilder second = createDummyFoldingBuilder("plain", "tree");

    LanguageFolding.INSTANCE.addExplicitExtension(PlainTextLanguage.INSTANCE, first);
    LanguageFolding.INSTANCE.addExplicitExtension(PlainTextLanguage.INSTANCE, second);

    try {
      FoldingUpdate.FoldingMap foldingMap = FoldingUpdate.getFoldingsFor(getProject(), getFile(), getEditor().getDocument(), false);
      Collection<FoldingDescriptor> descriptors = foldingMap.get(getFile());

      assert descriptors.size() == 1: "Only one descriptor allowed for the same text range. Descriptors: " + descriptors;
    }
    finally {
      LanguageFolding.INSTANCE.removeExplicitExtension(PlainTextLanguage.INSTANCE, first);
      LanguageFolding.INSTANCE.removeExplicitExtension(PlainTextLanguage.INSTANCE, second);
    }
  }

  @NotNull
  private FoldingBuilder createDummyFoldingBuilder(final String textToFold, final String placeholderText) {
    return new CustomFoldingBuilder() {
      @Override
      protected void buildLanguageFoldRegions(
        @NotNull List<FoldingDescriptor> descriptors,
        @NotNull PsiElement root,
        @NotNull Document document,
        boolean quick)
      {
        final int index = root.getText().indexOf(textToFold);
        descriptors.add(new NamedFoldingDescriptor(root, index, index + textToFold.length(), null, placeholderText));
      }

      @Override
      protected String getLanguagePlaceholderText(@NotNull ASTNode node, @NotNull TextRange range) {
        return "";
      }

      @Override
      protected boolean isRegionCollapsedByDefault(@NotNull ASTNode node) {
        return true;
      }
    };
  }


}