third_party/WebKit/Source/build/scripts/template_expander.py

   1 # Copyright (C) 2013 Google Inc. All rights reserved.
   2 #
   3 # Redistribution and use in source and binary forms, with or without
   4 # modification, are permitted provided that the following conditions are
   5 # met:
   6 #
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   9 #     * Redistributions in binary form must reproduce the above
  10 # copyright notice, this list of conditions and the following disclaimer
  11 # in the documentation and/or other materials provided with the
  12 # distribution.
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  14 # contributors may be used to endorse or promote products derived from
  15 # this software without specific prior written permission.
  16 #
  17 # THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
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  27 # OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
  28
  29 import os
  30 import sys
  31
  32 _current_dir = os.path.dirname(os.path.realpath(__file__))
  33 # jinja2 is in chromium's third_party directory
  34 # Insert at front to override system libraries, and after path[0] == script dir
  35 sys.path.insert(1, os.path.join(_current_dir, *([os.pardir] * 4)))
  36 import jinja2
  37
  38
  39 def apply_template(path_to_template, params, filters=None):
  40     dirname, basename = os.path.split(path_to_template)
  41     path_to_templates = os.path.join(_current_dir, 'templates')
  42     jinja_env = jinja2.Environment(
  43         loader=jinja2.FileSystemLoader([dirname, path_to_templates]),
  44         keep_trailing_newline=True,  # newline-terminate generated files
  45         lstrip_blocks=True,  # so can indent control flow tags
  46         trim_blocks=True)  # so don't need {%- -%} everywhere
  47     if filters:
  48         jinja_env.filters.update(filters)
  49     template = jinja_env.get_template(basename)
  50     return template.render(params)
  51
  52
  53 def use_jinja(template_file_name, filters=None):
  54     def real_decorator(generator):
  55         def generator_internal(*args, **kwargs):
  56             parameters = generator(*args, **kwargs)
  57             return apply_template(template_file_name, parameters, filters=filters)
  58         generator_internal.func_name = generator.func_name
  59         return generator_internal
  60     return real_decorator