Move DEPS file docs into a README.md

checkdeps/builddeps.py

 #!/usr/bin/env python
 # Copyright 2013 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.
 
 """Traverses the source tree, parses all found DEPS files, and constructs
 a dependency rule table to be used by subclasses.
 
-The format of the deps file:
-
-First you have the normal module-level deps. These are the ones used by
-gclient. An example would be:
-
-  deps = {
-    "base":"http://foo.bar/trunk/base"
-  }
-
-DEPS files not in the top-level of a module won't need this. Then you
-have any additional include rules. You can add (using "+") or subtract
-(using "-") from the previously specified rules (including
-module-level deps). You can also specify a path that is allowed for
-now but that we intend to remove, using "!"; this is treated the same
-as "+" when check_deps is run by our bots, but a presubmit step will
-show a warning if you add a new include of a file that is only allowed
-by "!".
-
-Note that for .java files, there is currently no difference between
-"+" and "!", even in the presubmit step.
-
-  include_rules = [
-    # Code should be able to use base (it's specified in the module-level
-    # deps above), but nothing in "base/evil" because it's evil.
-    "-base/evil",
-
-    # But this one subdirectory of evil is OK.
-    "+base/evil/not",
-
-    # And it can include files from this other directory even though there is
-    # no deps rule for it.
-    "+tools/crime_fighter",
-
-    # This dependency is allowed for now but work is ongoing to remove it,
-    # so you shouldn't add further dependencies on it.
-    "!base/evil/ok_for_now.h",
-  ]
-
-If you have certain include rules that should only be applied for some
-files within this directory and subdirectories, you can write a
-section named specific_include_rules that is a hash map of regular
-expressions to the list of rules that should apply to files matching
-them.  Note that such rules will always be applied before the rules
-from 'include_rules' have been applied, but the order in which rules
-associated with different regular expressions is applied is arbitrary.
-
-  specific_include_rules = {
-    ".*_(unit|browser|api)test\.cc": [
-      "+libraries/testsupport",
-    ],
-  }
-
-DEPS files may be placed anywhere in the tree. Each one applies to all
-subdirectories, where there may be more DEPS files that provide additions or
-subtractions for their own sub-trees.
-
-There is an implicit rule for the current directory (where the DEPS file lives)
-and all of its subdirectories. This prevents you from having to explicitly
-allow the current directory everywhere.  This implicit rule is applied first,
-so you can modify or remove it using the normal include rules.
-
-The rules are processed in order. This means you can explicitly allow a higher
-directory and then take away permissions from sub-parts, or the reverse.
-
-Note that all directory separators must be slashes (Unix-style) and not
-backslashes. All directories should be relative to the source root and use
-only lowercase.
+See README.md for the format of the deps file.
 """
 
 import copy
 import os.path
 import posixpath
 import subprocess
 
 from rules import Rule, Rules
 
 
@@ skipping 338 matching lines @@
     if dir_path_norm in self.directory_rules:
       return self.directory_rules[dir_path_norm]
 
     if parent_rules:
       self._ApplyDirectoryRulesAndSkipSubdirs(parent_rules, dir_path_local_abs)
     else:
       # If the parent directory should be skipped, then the current
       # directory should also be skipped.
       self.directory_rules[dir_path_norm] = None
     return self.directory_rules[dir_path_norm]