default to using linux platform

If there is no pages directory for the user's current platform, then
just assume it's a Linux-like and serve from there. Certain results
may be different (e.g. GNU grep vs BSD grep), but better than nothing.

Signed-off-by: Matthew Peveler <matt.peveler@gmail.com>

Author: MasterOdin

tests/test_tldr.py

@@ -59,3 +59,16 @@ def test_get_default_language(language, expected, monkeypatch):
 def test_get_default_language_unset(monkeypatch):
     monkeypatch.delenv("LANG", raising=False)
     assert tldr.get_default_language() is None
+
+
+@pytest.mark.parametrize("platform, expected", [
+    ("linux2", "linux"),
+    ("win32", "windows"),
+    ("darwin", "osx"),
+    ("sunos", "sunos"),
+    ("freebsd", "linux"),
+    ("aix", "linux"),
+])
+def test_get_platform(platform, expected):
+    with mock.patch("sys.platform", platform):
+        assert tldr.get_platform() == expected

tldr.py

@@ -172,6 +172,7 @@ def get_platform():
     for key in OS_DIRECTORIES:
         if sys.platform.startswith(key):
             return OS_DIRECTORIES[key]
+    return 'linux'
 
 
 def get_platform_list():