mojo: Starting generator for python bindings.

This generates constants for the python bindings.

R=pkl@chromium.org,cmasone@chromium.org

Review URL: https://codereview.chromium.org/517353002

Cr-Commit-Position: refs/heads/master@{#293105}

mojo/public/tools/bindings/generators/mojom_java_generator.py

@@ -95,11 +95,8 @@ def NameToComponent(name):
   name = re.sub('([^A-Z_])([A-Z])', r'\1_\2', name)
   return [x.lower() for x in name.split('_')]
 
-def CapitalizeFirst(string):
-  return string[0].upper() + string[1:]
-
 def UpperCamelCase(name):
-  return ''.join([CapitalizeFirst(x) for x in NameToComponent(name)])
+  return ''.join([x.capitalize() for x in NameToComponent(name)])
 
 def CamelCase(name):
   uccc = UpperCamelCase(name)

mojo/public/tools/bindings/generators/mojom_python_generator.py

+# Copyright 2014 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.
+
+"""Generates Python source files from a mojom.Module."""
+
+import re
+
+import mojom.generate.generator as generator
+import mojom.generate.module as mojom
+from mojom.generate.template_expander import UseJinja
+
+
+def NameToComponent(name):
+  # insert '_' between anything and a Title name (e.g, HTTPEntry2FooBar ->
+  # HTTP_Entry2_FooBar)
+  name = re.sub('([^_])([A-Z][^A-Z_]+)', r'\1_\2', name)
+  # insert '_' between non upper and start of upper blocks (e.g.,
+  # HTTP_Entry2_FooBar -> HTTP_Entry2_Foo_Bar)
+  name = re.sub('([^A-Z_])([A-Z])', r'\1_\2', name)
+  return [x.lower() for x in name.split('_')]
+
+def UpperCamelCase(name):
+  return ''.join([x.capitalize() for x in NameToComponent(name)])
+
+def CamelCase(name):
+  uccc = UpperCamelCase(name)
+  return uccc[0].lower() + uccc[1:]
+
+def ConstantStyle(name):
+  components = NameToComponent(name)
+  if components[0] == 'k':
+    components = components[1:]
+  return '_'.join([x.upper() for x in components])
+
+def GetNameForElement(element):
+  if isinstance(element, (mojom.NamedValue,
+                          mojom.Constant)):
+    return ConstantStyle(element.name)
+  raise Exception('Unexpected element: ' % element)
+
+def TranslateConstants(token):
+  if isinstance(token, (mojom.EnumValue, mojom.NamedValue)):
+    # Both variable and enum constants are constructed like:
+    # NamespaceUid.Struct[.Enum].CONSTANT_NAME
+    name = []
+    if token.imported_from:
+      name.append(token.imported_from['python_module'])
+    if token.parent_kind:
+      name.append(GetNameForElement(token.parent_kind))
+    if isinstance(token, mojom.EnumValue):
+      name.append(GetNameForElement(token))
+    else:
+      name.append(token.name)
+    return '.'.join(name)
+
+  if isinstance(token, mojom.BuiltinValue):
+    if token.value == 'double.INFINITY' or token.value == 'float.INFINITY':
+      return 'float(\'inf\')';
+    if (token.value == 'double.NEGATIVE_INFINITY' or
+        token.value == 'float.NEGATIVE_INFINITY'):
+      return 'float(\'-inf\')'
+    if token.value == 'double.NAN' or token.value == 'float.NAN':
+      return 'float(\'nan\')';
+
+  return token
+
+
+def ExpressionToText(value):
+  return TranslateConstants(value)
+
+
+class Generator(generator.Generator):
+
+  python_filters = {
+    'expression_to_text': ExpressionToText,
+    'name': GetNameForElement,
+  }
+
+  @UseJinja('python_templates/module.py.tmpl', filters=python_filters)
+  def GeneratePythonModule(self):
+    return {
+      'imports': self.GetImports(),
+      'module': self.module,
+    }
+
+  def GenerateFiles(self, args):
+    self.Write(self.GeneratePythonModule(),
+               '%s.py' % self.module.name.replace('.mojom', '_mojom'))
+
+  def GetImports(self):
+    for each in self.module.imports:
+      each['python_module'] = each['module_name'].replace('.mojom', '_mojom')
+    return self.module.imports
+
+  def GetJinjaParameters(self):
+    return {
+      'lstrip_blocks': True,
+      'trim_blocks': True,
+    }

mojo/public/tools/bindings/generators/python_templates/module.py.tmpl

+# Copyright 2014 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.
+{% if imports %}
+
+{% for import in imports %}
+import {{import.python_module}}
+{% endfor %}
+{% endif %}
+{#--- Constants #}
+{% if module.constants %}
+
+{% for constant in module.constants %}
+{{constant|name}} = {{constant.value|expression_to_text}}
+{% endfor %}
+{% endif %}

mojo/public/tools/bindings/mojom.gni

@@ -45,8 +45,10 @@ template("mojom") {
     "$generator_root/generators/js_templates/interface_definition.tmpl",
     "$generator_root/generators/js_templates/module.js.tmpl",
     "$generator_root/generators/js_templates/struct_definition.tmpl",
+    "$generator_root/generators/python_templates/module.py.tmpl",
     "$generator_root/generators/mojom_cpp_generator.py",
     "$generator_root/generators/mojom_js_generator.py",
+    "$generator_root/generators/mojom_python_generator.py",
     "$generator_root/pylib/mojom/__init__.py",
     "$generator_root/pylib/mojom/error.py",
     "$generator_root/pylib/mojom/generate/__init__.py",
@@ -69,6 +71,9 @@ template("mojom") {
   generator_js_outputs = [
     "{{source_gen_dir}}/{{source_name_part}}.mojom.js",
   ]
+  generator_python_outputs = [
+    "{{source_gen_dir}}/{{source_name_part}}_mojom.py",
+  ]
 
   target_visibility = ":$target_name"
 
@@ -78,7 +83,9 @@ template("mojom") {
     script = generator_script
     inputs = generator_sources
     sources = invoker.sources
-    outputs = generator_cpp_outputs + generator_js_outputs
+    outputs = generator_cpp_outputs +
+              generator_js_outputs +
+              generator_python_outputs
     args = [
       "{{source}}",
       "--use_chromium_bundled_pylibs",

mojo/public/tools/bindings/mojom_bindings_generator.gypi

@@ -52,9 +52,11 @@
         '<(DEPTH)/mojo/public/tools/bindings/generators/js_templates/interface_definition.tmpl',
         '<(DEPTH)/mojo/public/tools/bindings/generators/js_templates/module.js.tmpl',
         '<(DEPTH)/mojo/public/tools/bindings/generators/js_templates/struct_definition.tmpl',
+        '<(DEPTH)/mojo/public/tools/bindings/generators/python_templates/module.py.tmpl',
         '<(DEPTH)/mojo/public/tools/bindings/generators/mojom_cpp_generator.py',
         '<(DEPTH)/mojo/public/tools/bindings/generators/mojom_java_generator.py',
         '<(DEPTH)/mojo/public/tools/bindings/generators/mojom_js_generator.py',
+        '<(DEPTH)/mojo/public/tools/bindings/generators/mojom_python_generator.py',
         '<(DEPTH)/mojo/public/tools/bindings/pylib/mojom/__init__.py',
         '<(DEPTH)/mojo/public/tools/bindings/pylib/mojom/error.py',
         '<(DEPTH)/mojo/public/tools/bindings/pylib/mojom/generate/__init__.py',
@@ -73,6 +75,7 @@
         '<(SHARED_INTERMEDIATE_DIR)/<(mojom_base_output_dir)/<(RULE_INPUT_DIRNAME)/<(RULE_INPUT_ROOT).mojom.cc',
         '<(SHARED_INTERMEDIATE_DIR)/<(mojom_base_output_dir)/<(RULE_INPUT_DIRNAME)/<(RULE_INPUT_ROOT).mojom.h',
         '<(SHARED_INTERMEDIATE_DIR)/<(mojom_base_output_dir)/<(RULE_INPUT_DIRNAME)/<(RULE_INPUT_ROOT).mojom.js',
+        '<(SHARED_INTERMEDIATE_DIR)/<(mojom_base_output_dir)/<(RULE_INPUT_DIRNAME)/<(RULE_INPUT_ROOT).mojom.py',
         '<(SHARED_INTERMEDIATE_DIR)/<(mojom_base_output_dir)/<(RULE_INPUT_DIRNAME)/<(RULE_INPUT_ROOT).mojom-internal.h',
       ],
       'action': [

mojo/public/tools/bindings/mojom_bindings_generator.py

@@ -56,6 +56,9 @@ def LoadGenerators(generators_string):
     elif generator_name.lower() == "java":
       generator_name = os.path.join(script_dir, "generators",
                                     "mojom_java_generator.py")
+    elif generator_name.lower() == "python":
+      generator_name = os.path.join(script_dir, "generators",
+                                    "mojom_python_generator.py")
     # Specified generator python module:
     elif generator_name.endswith(".py"):
       pass
@@ -166,7 +169,8 @@ def main():
   parser.add_argument("-o", "--output_dir", dest="output_dir", default=".",
                       help="output directory for generated files")
   parser.add_argument("-g", "--generators", dest="generators_string",
-                      metavar="GENERATORS", default="c++,javascript,java",
+                      metavar="GENERATORS",
+                      default="c++,javascript,java,python",
                       help="comma-separated list of generators")
   parser.add_argument("--debug_print_intermediate", action="store_true",
                       help="print the intermediate representation")

mojo/python/tests/bindings_constants_unittest.py

+# Copyright 2014 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 math
+import unittest
+
+# Generated files
+# pylint: disable=F0401
+import sample_service_mojom
+
+
+class ConstantBindingsTest(unittest.TestCase):
+
+  def test_constant_generation(self):
+    self.assertEquals(sample_service_mojom.TWELVE, 12)
+    self.assertEquals(sample_service_mojom.TOO_BIG_FOR_SIGNED_INT64,
+                      9999999999999999999)
+    self.assertEquals(sample_service_mojom.DOUBLE_INFINITY,
+                      float('inf'))
+    self.assertEquals(sample_service_mojom.DOUBLE_NEGATIVE_INFINITY,
+                      float('-inf'))
+    self.assertTrue(math.isnan(sample_service_mojom.DOUBLE_NA_N))
+    self.assertEquals(sample_service_mojom.FLOAT_INFINITY,
+                      float('inf'))
+    self.assertEquals(sample_service_mojom.FLOAT_NEGATIVE_INFINITY,
+                      float('-inf'))
+    self.assertTrue(math.isnan(sample_service_mojom.FLOAT_NA_N))

mojo/tools/run_mojo_python_bindings_tests.py

@@ -23,6 +23,12 @@ class PythonBindingsTestRunner(MojoPythonTestRunner):
       python_build_dir = os.path.join(args.build_dir, 'python')
       if python_build_dir not in sys.path:
         sys.path.append(python_build_dir)
+      python_gen_dir = os.path.join(
+          args.build_dir,
+          'gen', 'mojo', 'public', 'interfaces', 'bindings', 'tests')
+      print python_gen_dir
+      if python_gen_dir not in sys.path:
+        sys.path.append(python_gen_dir)
 
 
 def main():