Rewrite the logic to resolve package-relative paths so we can remove …

…the "asset" library (#247)

* implement the new function resolve_package_path
* add tests
provide tests for the new function resolve_package_path() and the
"include package()" statement in the config
* remove "asset" from the list of dependencies
* remove "import asset"
* compatibility with python 2.7

pyhocon/config_parser.py

@@ -1,6 +1,7 @@
 import codecs
 import contextlib
 import copy
+import imp
 import itertools
 import logging
 import os
@@ -29,7 +30,6 @@ def fixed_get_attr(self, item):
 
     pyparsing.ParseResults.__getattr__ = fixed_get_attr
 
-import asset
 from pyhocon.config_tree import (ConfigInclude, ConfigList, ConfigQuotedString,
                                  ConfigSubstitution, ConfigTree,
                                  ConfigUnquotedString, ConfigValues, NoneValue)
@@ -349,7 +349,7 @@ def include_config(instring, loc, token):
                 if final_tokens[0] == 'url':
                     url = value
                 elif final_tokens[0] == 'package':
-                    file = asset.load(value).filename
+                    file = cls.resolve_package_path(value)
                 else:
                     file = value
 
@@ -712,6 +712,25 @@ def resolve_substitutions(cls, config, accept_unresolved=False):
         cls._final_fixup(config)
         return has_unresolved
 
+    @classmethod
+    def resolve_package_path(cls, package_path):
+        """
+        Resolve the path to a file inside a Python package. Expected format: "PACKAGE:PATH"
+
+        Example: "my_package:foo/bar.conf" will resolve file 'bar.conf' in folder 'foo'
+        inside package 'my_package', which could result in a path like
+        '/path/to/.venv/lib/python3.7/site-packages/my_package/foo/bar.conf'
+
+        :param package_path: the package path, formatted as "PACKAGE:PATH"
+        :return: the absolute path to the specified file inside the specified package
+        """
+        if ':' not in package_path:
+            raise ValueError("Expected format is 'PACKAGE:PATH'")
+        package_name, path_relative = package_path.split(':', 1)
+        package_dir = imp.find_module(package_name)[1]
+        path_abs = os.path.join(package_dir, path_relative)
+        return path_abs
+
 
 class ListParser(TokenConverter):
     """Parse a list [elt1, etl2, ...]

setup.py

@@ -51,7 +51,7 @@ def run_tests(self):
     packages=[
         'pyhocon',
     ],
-    install_requires=['pyparsing>=2.0.3', 'asset'],
+    install_requires=['pyparsing>=2.0.3'],
     extras_require={
         'Duration': ['python-dateutil>=2.8.0']
     },

tests/test_config_parser.py

@@ -2,12 +2,12 @@
 
 import json
 import os
+import shutil
 import tempfile
 from collections import OrderedDict
 from datetime import timedelta
 
 from pyparsing import ParseBaseException, ParseException, ParseSyntaxException
-import asset
 import mock
 import pytest
 from pyhocon import (ConfigFactory, ConfigParser, ConfigSubstitutionException, ConfigTree)
@@ -1267,26 +1267,42 @@ def test_include_missing_required_file(self):
                 """
             )
 
-    def test_include_asset_file(self, monkeypatch):
-        with tempfile.NamedTemporaryFile('w') as fdin:
-            fdin.write('{a: 1, b: 2}')
-            fdin.flush()
-
-            def load(*args, **kwargs):
-                class File(object):
-                    def __init__(self, filename):
-                        self.filename = filename
-
-                return File(fdin.name)
-
-            monkeypatch.setattr(asset, "load", load)
-
+    def test_resolve_package_path(self):
+        path = ConfigParser.resolve_package_path("pyhocon:config_parser.py")
+        assert os.path.exists(path)
+
+    def test_resolve_package_path_format(self):
+        with pytest.raises(ValueError):
+            ConfigParser.resolve_package_path("pyhocon/config_parser.py")
+
+    def test_resolve_package_path_missing(self):
+        with pytest.raises(ImportError):
+            ConfigParser.resolve_package_path("non_existent_module:foo.py")
+
+    def test_include_package_file(self, monkeypatch):
+        temp_dir = tempfile.mkdtemp()
+        try:
+            module_dir = os.path.join(temp_dir, 'my_module')
+            module_conf = os.path.join(module_dir, 'my.conf')
+            # create the module folder and necessary files (__init__ and config)
+            os.mkdir(module_dir)
+            open(os.path.join(module_dir, '__init__.py'), 'a').close()
+            with open(module_conf, 'w') as fdin:
+                fdin.write("{c: 3}")
+            # add the temp dir to sys.path so that 'my_module' can be discovered
+            monkeypatch.syspath_prepend(temp_dir)
+            # load the config and include the other config file from 'my_module'
             config = ConfigFactory.parse_string(
                 """
-                include package("dotted.name:asset/config_file")
+                a: 1
+                b: 2
+                include package("my_module:my.conf")
                 """
             )
-            assert config['a'] == 1
+            # check that the contents of both config files are available
+            assert dict(config.as_plain_ordered_dict()) == {'a': 1, 'b': 2, 'c': 3}
+        finally:
+            shutil.rmtree(temp_dir, ignore_errors=True)
 
     def test_include_dict(self):
         expected_res = {