snipper_provider (#4)

* add class initialization skeleton

* moved mock data to test files

* Use patch instead of changing snippetProvider object

* Moved snippet provider instance to snippet provider module

* Implemented initialize method

* Fixes from manual testing

* Added docstrings and refactored a bit

* Implemented most of the tests for snippet provider

* Finished initialization test implementation

* Added os.path.join use to ensure multiple platform support

homotopy/snippet_provider.py

@@ -1,15 +1,43 @@
+import os
+import json
+import logging
 
 
 class SnippetProvider:
     """
     Class for translating simple snippets into code.
+    Uses a database provided in json files located in path variable.
     """
 
-    data = {
-        "for": "for # in !:\n\tpass"
-    }
+    def __init__(self, language="", path=[]):
+        """
+        Initialize snippet provider instance.
+        :param language: language to compile to
+        :param path: list of directories to search for json files containing snippets
+        """
+        self.data = {}
+        self.language = language
+        self.path = path
+        for item in self.path:
+            for file in filter(lambda x: x.endswith(".json"), os.listdir(item)):
+                try:
+                    for snippet in filter(lambda x: x["language"].lower() == self.language.lower(), json.load(open(os.path.join(item, file)))):
+                        if snippet["name"] in self.data:
+                            logging.warning("Multiple definition for %s" % snippet["name"])
+                        else:
+                            self.data[snippet["name"]] = snippet["snippet"]
+                except (ValueError, OSError):
+                    logging.warning("Could not get data from file %s" % file, exc_info=True)
 
     def __getitem__(self, item):
-        if item in SnippetProvider.data:
-            return SnippetProvider.data[item]
+        """
+        Expand single snippet
+        :param item: snippet
+        :return: snippet expansion
+        """
+        if item in self.data:
+            return self.data[item]
         return item
+
+
+snippetProvider = SnippetProvider()

homotopy/syntax_tree.py

@@ -1,6 +1,4 @@
-from homotopy.snippet_provider import SnippetProvider
-
-snippetProvider = SnippetProvider()
+from homotopy.snippet_provider import snippetProvider
 
 
 class Snippet:

test/testSnippet_provider.py

@@ -1,11 +1,61 @@
 from unittest import TestCase
+from unittest.mock import patch, MagicMock
+from unittest.mock import mock_open
+
+import os
 
 import homotopy.snippet_provider as sp
 
 
 class TestSnippetProvider(TestCase):
-    def test_basic(self):
+    def test_getitem(self):
         provider = sp.SnippetProvider()
 
+        provider.data = {
+            "for": "for # in !:\n\tpass"
+        }
+
         self.assertEqual(provider['for'], "for # in !:\n\tpass")
         self.assertEqual(provider['i==5'], "i==5")
+
+    @patch('os.listdir')
+    def test_initialization(self, listdir):
+        listdir.return_value = ['test.json', 'test.txt']
+
+        self.assertDictEqual(sp.SnippetProvider().data, {}, "Snippet provider should be empty.")
+
+        with patch('builtins.open', mock_open(read_data='[{"name": "for","language": "C++","snippet": "if(#){$}"}]')) as m:
+            provider = sp.SnippetProvider("c++", ["test"])
+
+            self.assertEqual("if(#){$}", provider["for"])
+
+            m.assert_called_once_with(os.path.join("test", "test.json"))
+
+            listdir.assert_called_once_with("test")
+
+        with patch('builtins.open', mock_open(read_data='[{"name": "for","language": "C++","snippet": "if(#){$}"}]')) as m:
+            provider = sp.SnippetProvider("java", ["test"])
+
+            self.assertEqual("for", provider["for"])
+
+        with patch('logging.warning', MagicMock()) as m:
+            with patch('builtins.open', mock_open()) as m_open:
+                m_open.side_effect = IOError()
+
+                provider = sp.SnippetProvider("c++", ["test"])
+
+                m.assert_called_once_with("Could not get data from file test.json", exc_info=True)
+
+        with patch('logging.warning', MagicMock()) as m:
+            with patch('builtins.open', mock_open(read_data='invalidJSON')) as m_open:
+                provider = sp.SnippetProvider("c++", ["test"])
+
+                m.assert_called_once_with("Could not get data from file test.json", exc_info=True)
+
+        with patch('logging.warning', MagicMock()) as m:
+            with patch('builtins.open', mock_open(
+                read_data='[{"name": "for","language": "C++","snippet": "if(#){$}"}' 
+                          ',{"name": "for","language": "C++","snippet": "if(#){$}"}]')) as m_open:
+                provider = sp.SnippetProvider("c++", ["test"])
+
+                m.assert_called_once_with("Multiple definition for for")

test/testSyntax_tree.py

@@ -1,4 +1,5 @@
 from unittest import TestCase
+from unittest.mock import patch
 
 import homotopy.syntax_tree as st
 
@@ -21,10 +22,12 @@ def test_eq(self):
 
         self.assertFalse(st.SimpleSnippet('if') != st.SimpleSnippet('if'))
 
-
-    def test_compile(self):
+    @patch('homotopy.snippet_provider.SnippetProvider.__getitem__')
+    def test_compile(self, mockProvider):
         self.assertIsNone(st.Snippet().compile())
 
+        mockProvider.side_effect = lambda x: x if x != "for" else "for # in !:\n\tpass"
+
         self.assertEqual(
             st.CompositeSnippet(
                 st.CompositeSnippet(st.SimpleSnippet('for'), '#', st.SimpleSnippet('i')),