Refactor PDFium python test utilities.

testing/tools/common.py

Index: testing/tools/common.py
diff --git a/testing/tools/common.py b/testing/tools/common.py
new file mode 100755
index 0000000000000000000000000000000000000000..14745a8a3e62348254e111d9999a35eec3a0ceaf
--- /dev/null
+++ b/testing/tools/common.py
@@ -0,0 +1,70 @@
+#!/usr/bin/env python
+# Copyright 2015 The PDFium 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
+import sys
+
+def os_name():
+  if sys.platform.startswith('linux'):
+    return 'linux'
+  if sys.platform.startswith('win'):
+    return 'win'
+  if sys.platform.startswith('darwin'):
+    return 'mac'
+  raise Exception('Confused, can not determine OS, aborting.')
+
+
+class DirectoryFinder:
+  '''A class for finding directories and paths under either a standalone
+  checkout or a chromium checkout of PDFium.'''
+
+  def __init__(self, build_location):
+    # |build_location| is typically "out/Debug" or "out/Release".
+    # Expect |my_dir| to be .../pdfium/testing/tools.
+    self.my_dir = os.path.dirname(os.path.realpath(__file__))
+    self.testing_dir = os.path.dirname(self.my_dir)
+    if (os.path.basename(self.my_dir) != 'tools' or
+        os.path.basename(self.testing_dir) != 'testing'):
+      raise Exception('Confused, can not find pdfium root directory, aborting.')
+    self.pdfium_dir = os.path.dirname(self.testing_dir)
+    # Find path to build directory.  This depends on whether this is a
+    # standalone build vs. a build as part of a chromium checkout. For
+    # standalone, we expect a path like .../pdfium/out/Debug, but for
+    # chromium, we expect a path like .../src/out/Debug two levels
+    # higher (to skip over the third_party/pdfium path component under
+    # which chromium sticks pdfium).
+    self.base_dir = self.pdfium_dir
+    one_up_dir = os.path.dirname(self.base_dir)
+    two_up_dir = os.path.dirname(one_up_dir)
+    if (os.path.basename(two_up_dir) == 'src' and
+        os.path.basename(one_up_dir) == 'third_party'):
+      self.base_dir = two_up_dir
+    self.build_dir = os.path.join(self.base_dir, build_location)
+    self.os_name = os_name()
+
+  def ExecutablePath(self, name):
+    '''Finds compiled binaries under the build path.'''
+    result = os.path.join(self.build_dir, name)
+    if self.os_name == 'win':
+      result = result + '.exe'
+    return result
+
+  def ScriptPath(self, name):
+    '''Finds other scripts in the same directory as this one.'''
+    return os.path.join(self.my_dir, name)
+
+  def WorkingDir(self, other_components=''):
+    '''Places generated files under the build directory, not source dir.'''
+    result = os.path.join(self.build_dir, 'gen', 'pdfium')
+    if other_components:
+      result = os.path.join(result, other_components)
+    return result
+
+  def TestingDir(self, other_components=''):
+    '''Finds test files somewhere under the testing directory.'''
+    result = self.testing_dir
+    if other_components:
+      result = os.path.join(result, other_components)
+    return result