From aabf9f503784321f026e6028a5c5ff6066d4cfda Mon Sep 17 00:00:00 2001
From: lilydjwg <lilydjwg@gmail.com>
Date: Sat, 22 Sep 2018 13:12:25 +0800
Subject: [PATCH] cache get_version results

closes #81
---
 nvchecker/get_version.py | 11 +++++++++++
 tests/test_cache.py      | 12 ++++++++++++
 2 files changed, 23 insertions(+)
 create mode 100644 tests/test_cache.py

diff --git a/nvchecker/get_version.py b/nvchecker/get_version.py
index 96be522..9e4affc 100644
--- a/nvchecker/get_version.py
+++ b/nvchecker/get_version.py
@@ -38,7 +38,18 @@ def substitute_version(version, name, conf):
   # No substitution rules found. Just return the original version string.
   return version
 
+_cache = {}
+
 async def get_version(name, conf, **kwargs):
+  cache_key = tuple(sorted(conf.items()))
+  if cache_key in _cache:
+    return _cache[cache_key]
+
+  version = await _get_version_real(name, conf, **kwargs)
+  _cache[cache_key] = version
+  return version
+
+async def _get_version_real(name, conf, **kwargs):
   for key in handler_precedence:
     if key in conf:
       func = import_module('.source.' + key, __package__).get_version
diff --git a/tests/test_cache.py b/tests/test_cache.py
new file mode 100644
index 0000000..455fd54
--- /dev/null
+++ b/tests/test_cache.py
@@ -0,0 +1,12 @@
+# MIT licensed
+# Copyright (c) 2018 lilydjwg <lilydjwg@gmail.com>, et al.
+
+import pytest
+pytestmark = pytest.mark.asyncio
+
+async def test_cache(get_version):
+  a = await get_version("a", {"cmd": "date +%%N"})
+  b = await get_version("b", {"cmd": "date +%%N"})
+  c = await get_version("c", {"cmd": "date"})
+  assert a == b
+  assert a != c