NOT TO COMMITTED: Update mojo sdk to rev 0018e6a91b75bcb941c867f8a7aa1753c3b53a13

third_party/mojo/src/mojo/public/tools/mojom_fetcher/pylib/fetcher/dependency.py

Index: third_party/mojo/src/mojo/public/tools/mojom_fetcher/pylib/fetcher/dependency.py
diff --git a/third_party/mojo/src/mojo/public/tools/mojom_fetcher/pylib/fetcher/dependency.py b/third_party/mojo/src/mojo/public/tools/mojom_fetcher/pylib/fetcher/dependency.py
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index 0000000000000000000000000000000000000000..a4716e4e86ac2b4f085823c529a8eb0dca0cccf1
--- /dev/null
+++ b/third_party/mojo/src/mojo/public/tools/mojom_fetcher/pylib/fetcher/dependency.py
@@ -0,0 +1,97 @@
+# Copyright 2015 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.
+
+import os
+
+
+class Dependency(object):
+  """Dependency represents an import request from one mojom file to another.
+  """
+  def __init__(self, repository, importer, imported):
+    self._repository = repository
+    self._importer_filename = os.path.normpath(importer)
+    self._imported_filename = os.path.normpath(imported)
+
+  def __str__(self):
+    return str(self.__dict__)
+
+  def __eq__(self, other):
+    return self.__dict__ == other.__dict__
+
+  def get_importer(self):
+    """Returns the name and full path of the file doing the import."""
+    return self._importer_filename
+
+  def get_imported(self):
+    """Returns the imported file (filename and path)."""
+    return self._imported_filename
+
+  def is_sdk_dep(self):
+    """Returns whether this dependency is from the mojo SDK."""
+    return (self._imported_filename.startswith("mojo/public/") or
+            self._imported_filename.startswith("//mojo/public/"))
+
+  def _is_in_external(self):
+    """Returns whether this dependency is under the external directory."""
+    common = os.path.commonprefix((self._repository.get_external_directory(),
+                                   self._importer_filename))
+    return common == self._repository.get_external_directory()
+
+  def maybe_is_a_url(self):
+    """Returns whether this dependency may be pointing to a downloadable
+    ressource."""
+    if self._is_in_external() and not self.is_sdk_dep():
+      # External dependencies may refer to other dependencies by relative path,
+      # so they can always be URLs.
+      return True
+
+    base, _ = self._imported_filename.split(os.path.sep, 1)
+    if not '.' in base:
+      # There is no dot separator in the first part of the path; it cannot be a
+      # URL.
+      return False
+    return True
+
+  def generate_candidate_urls(self):
+    """Generates possible paths where to download this dependency. It is
+    expected that at most one of them should work."""
+    candidates = []
+
+    base, _ = self._imported_filename.split(os.path.sep, 1)
+    if '.' in base and not base.startswith('.'):
+      # This import may be an absolute URL path (without scheme).
+      candidates.append(self._imported_filename)
+
+    # External dependencies may refer to other dependencies by relative path.
+    if self._is_in_external():
+      directory = os.path.relpath(os.path.dirname(self._importer_filename),
+                                  self._repository.get_external_directory())
+
+      # This is to handle the case where external dependencies use
+      # imports relative to a directory upper in the directory structure. As we
+      # don't know which directory, we need to go through all of them.
+      while len(directory) > 0:
+        candidates.append(os.path.join(directory, self._imported_filename))
+        directory = os.path.dirname(directory)
+    return candidates
+
+  def get_search_path_for_dependency(self):
+    """Return all possible search paths for this dependency."""
+
+    # Root directory and external directory are always included.
+    search_paths = set([self._repository.get_repo_root_directory(),
+                        self._repository.get_external_directory()])
+    # Local import paths
+    search_paths.add(os.path.dirname(self._importer_filename))
+
+    if self._is_in_external():
+      directory = os.path.dirname(self._importer_filename)
+
+      # This is to handle the case where external dependencies use
+      # imports relative to a directory upper in the directory structure. As we
+      # don't know which directory, we need to go through all of them.
+      while self._repository.get_external_directory() in directory:
+        search_paths.add(directory)
+        directory = os.path.dirname(directory)
+    return search_paths