IDEA-66303 Action to remove BOM from file

platform/platform-impl/src/com/intellij/openapi/editor/actions/RemoveBomAction.java

@@ -0,0 +1,115 @@
+/*
+ * Copyright 2000-2011 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.openapi.editor.actions;
+
+import com.intellij.openapi.actionSystem.AnAction;
+import com.intellij.openapi.actionSystem.AnActionEvent;
+import com.intellij.openapi.actionSystem.PlatformDataKeys;
+import com.intellij.openapi.diagnostic.Logger;
+import com.intellij.openapi.project.DumbAware;
+import com.intellij.openapi.vfs.VirtualFile;
+import com.intellij.openapi.vfs.newvfs.NewVirtualFile;
+import org.jetbrains.annotations.NotNull;
+
+import java.io.IOException;
+import java.util.ArrayList;
+import java.util.List;
+
+/**
+ * Allows to remove <a href="http://unicode.org/faq/utf_bom.html">file's BOM</a> (if any).
+ * 
+ * @author Denis Zhdanov
+ * @since 3/30/11 11:14 AM
+ */
+public class RemoveBomAction extends AnAction implements DumbAware {
+
+  private static final Logger LOG = Logger.getInstance("#" + RemoveBomAction.class);
+  
+  public RemoveBomAction() {
+    super("Remove BOM");
+  }
+
+  @Override
+  public void actionPerformed(AnActionEvent e) {
+    VirtualFile[] files = PlatformDataKeys.VIRTUAL_FILE_ARRAY.getData(e.getDataContext());
+    if (files == null) {
+      return;
+    }
+    List<VirtualFile> filesToProcess = getFilesWithBom(files, true);
+    for (VirtualFile virtualFile : filesToProcess) {
+      byte[] bom = virtualFile.getBOM();
+      assert bom != null;
+      if (virtualFile instanceof NewVirtualFile) {
+        virtualFile.setBOM(null);
+        NewVirtualFile file = (NewVirtualFile)virtualFile;
+        try {
+          byte[] bytes = file.contentsToByteArray();
+          byte[] contentWithStrippedBom = new byte[bytes.length - bom.length];
+          System.arraycopy(bytes, bom.length, contentWithStrippedBom, 0, contentWithStrippedBom.length);
+          file.setBinaryContent(contentWithStrippedBom);
+        }
+        catch (IOException ex) {
+          LOG.warn("Unexpected exception occurred on attempt to remove BOM from file " + file, ex);
+        }
+      }
+    }
+  }
+
+  @Override
+  public void update(AnActionEvent e) {
+    VirtualFile[] files = PlatformDataKeys.VIRTUAL_FILE_ARRAY.getData(e.getDataContext());
+    if (files == null) {
+      e.getPresentation().setEnabled(false);
+      return;
+    }
+
+    e.getPresentation().setEnabled(!getFilesWithBom(files, false).isEmpty());
+  }
+
+  /**
+   * Recursively traverses contents of the given file roots (any root may be directory) and returns files that have
+   * {@link VirtualFile#getBOM() BOM} defined.
+   * 
+   * @param roots   VFS roots to traverse
+   * @param all     flag the defines if all files with {@link VirtualFile#getBOM() BOM} should be collected or just any of them
+   * @return        collection of detected files with defined {@link VirtualFile#getBOM() BOM} if any; empty collectio otherwise
+   */
+  @NotNull
+  private static List<VirtualFile> getFilesWithBom(@NotNull VirtualFile[] roots, boolean all) {
+    List<VirtualFile> result = new ArrayList<VirtualFile>();
+    for (VirtualFile root : roots) {
+      if (!all && !result.isEmpty()) {
+        break;
+      }
+      getFilesWithBom(root, result, all);
+    }
+    return result;
+  }
+  
+  private static void getFilesWithBom(@NotNull VirtualFile root, @NotNull List<VirtualFile> result, boolean all) {
+    if (root.isDirectory()) {
+      for (VirtualFile child : root.getChildren()) {
+        if (!all && !result.isEmpty()) {
+          return;
+        }
+        getFilesWithBom(child, result, all);
+      }
+    }
+    else if (root.getBOM() != null) {
+      result.add(root);  
+    }
+  }
+}

platform/platform-resources/src/idea/LangActions.xml

@@ -451,6 +451,8 @@
       <reference ref="ExternalToolsGroup"/>
       <separator/>
       <reference ref="ProjectViewPopupMenuSettingsGroup"/>
+      <separator/>
+      <reference ref="RemoveBom"/>
     </group>
 
     <group id="NavbarPopupMenu">

platform/platform-resources/src/idea/PlatformActions.xml

@@ -143,6 +143,7 @@
         <group id="ChangeFileEncodingGroup" popup="true" class="com.intellij.openapi.vfs.encoding.ChangeEncodingUpdateGroup">
           <action id="ChangeFileEncodingGroupAction" class="com.intellij.openapi.vfs.encoding.ChangeFileEncodingGroup" text=""/>
         </group>
+        <action id="RemoveBom" class="com.intellij.openapi.editor.actions.RemoveBomAction"/>
         <action id="ToggleReadOnlyAttribute" class="com.intellij.ide.actions.ToggleReadOnlyAttributeAction"/>
         <separator/>
         <action id="Exit" class="com.intellij.ide.actions.ExitAction"/>
@@ -337,6 +338,8 @@
       <separator/>
       <action id="CompareClipboardWithSelection" class="com.intellij.openapi.diff.actions.CompareClipboardWithSelection"/>
       <reference ref="ChangeFileEncodingGroup"/>
+      <separator/>
+      <reference ref="RemoveBom"/>
     </group>
 
     <group id="EditorTabPopupMenu">