Minimize dependency of user scripts....

base/file_path.cc

 // Copyright (c) 2008 The Chromium Authors. All rights reserved.
 // Use of this source code is governed by a BSD-style license that can be
 // found in the LICENSE file.
 
 #include "base/file_path.h"
 #include "base/logging.h"
 
 // These includes are just for the *Hack functions, and should be removed
 // when those functions are removed.
 #include "base/string_piece.h"
@@ skipping 140 matching lines @@
 }
 
 bool FilePath::operator!=(const FilePath& that) const {
 #if defined(FILE_PATH_USES_DRIVE_LETTERS)
   return !EqualDriveLetterCaseInsensitive(this->path_, that.path_);
 #else  // defined(FILE_PATH_USES_DRIVE_LETTERS)
   return path_ != that.path_;
 #endif  // defined(FILE_PATH_USES_DRIVE_LETTERS)
 }
 
+bool FilePath::AppendAndResolveRelative(const FilePath& relative_path,

[Mark Mentovai, 2009/10/23 21:29:40]

This is wrong and we need to remove it.

We can't resolve .. without referencing the disk.  (Think symbolic links.)

We can't reference the disk in FilePath.

If you need to resolve .., and you need to hit the disk, you need something in
file_util, not file_path.

+                                        FilePath* path) const {
+  DCHECK(path);
+  if (!path || relative_path.IsAbsolute())
+    return false;
+
+  FilePath full_path = Append(relative_path);
+  // Is it worth looking for parent references?
+  if (!full_path.ReferencesParent()) {
+    *path = full_path;
+    return true;
+  }
+
+  // If the parent has a drive letter, then we must not remove the first
+  // component, which is the drive letter.
+  bool drive_letter = (FindDriveLetter(full_path.path_) !=
+                       FilePath::StringType::npos);
+
+  std::vector<FilePath::StringType> components;
+  full_path.GetComponents(&components);
+  std::vector<FilePath::StringType>::iterator it = components.begin();
+  // Start by removing any kCurrentDirectory component, since they may
+  // fool us into not going back to the appropriate parent level.
+  for (; it != components.end(); ++it) {
+    if (*it == kCurrentDirectory) {
+      // erase returns an iterator to the next component.
+      it = components.erase(it);
+      // So now, go back to previous iterator,
+      // so that we can appropriately process the next one as we loop.
+      --it;
+    }
+  }
+
+  // Now parse the component looking for kParentDirectory and remove them as
+  // well as the previous component.
+  it = components.begin();
+  for (; it != components.end(); ++it) {
+    if (*it == kParentDirectory) {
+      // Did we reach the beginning?
+      if (it == components.begin() ||
+          (drive_letter && (it - 1) == components.begin())) {
+        return false;
+      }
+      // Remove the previous component, as well as the current one.
+      std::vector<FilePath::StringType>::iterator previous = it - 1;
+      // Unless the previous is at the beginning.
+      if (previous == components.begin() ||
+          (drive_letter && (previous - 1) == components.begin())) {
+        return false;
+      }
+      // vector::erase doesn't erase _Last, it erases [_First, _Last[,
+      // so we must increment current which we want erased.
+      it = components.erase(previous, it + 1);
+      // And go back to previous so that we can process the next one as we loop.
+      --it;
+    }
+  }
+
+  // Now reconstruct the path with the components that were left in.
+  it = components.begin();
+  // We start with the first component, in case it is absolute
+  // and absolute paths can't be appended.
+  *path = FilePath(*it);
+  for (++it; it != components.end(); ++it)
+    *path = path->Append(*it);
+
+  return true;
+}
+
 bool FilePath::IsParent(const FilePath& child) const {
   return AppendRelativePath(child, NULL);
 }
 
 bool FilePath::AppendRelativePath(const FilePath& child,
                                   FilePath* path) const {
   std::vector<FilePath::StringType> parent_components;
   std::vector<FilePath::StringType> child_components;
   GetComponents(&parent_components);
   child.GetComponents(&child_components);
@@ skipping 210 matching lines @@
     return FilePath(component);
   }
 
   FilePath new_path(path_);
   new_path.StripTrailingSeparatorsInternal();
 
   // Don't append a separator if the path is empty (indicating the current
   // directory) or if the path component is empty (indicating nothing to
   // append).
   if (component.length() > 0 && new_path.path_.length() > 0) {
-
     // Don't append a separator if the path still ends with a trailing
     // separator after stripping (indicating the root directory).
     if (!IsSeparator(new_path.path_[new_path.path_.length() - 1])) {
-
       // Don't append a separator if the path is just a drive letter.
       if (FindDriveLetter(new_path.path_) + 1 != new_path.path_.length()) {
         new_path.path_.append(1, kSeparators[0]);
       }
     }
   }
 
   new_path.path_.append(component);
   return new_path;
 }
@@ skipping 73 matching lines @@
 
   std::vector<FilePath::StringType>::const_iterator it = components.begin();
   for (; it != components.end(); ++it) {
     const FilePath::StringType& component = *it;
     if (component == kParentDirectory)
       return true;
   }
   return false;
 }