Add `readmes_dir` function.

* gd_diff.py (readmes_dir): New function.
* tests/test_gd_diff.py (test_readmes_dir): Test for `readmes_dir`
  function.

2 files changed, 28 insertions, 0 deletions

diff --git a/gd_diff.py b/gd_diff.py
index 63621a0..43da2b7 100644
--- a/gd_diff.py
+++ b/gd_diff.py
@@ -241,6 +241,22 @@ def pkgs_dir():
     return pd
 
 
+def readmes_dir(release):
+    """Return readmes directory for `release`.
+
+    As a side effect, the directory is created if it does not exist.
+    """
+    rd = os.path.join(config_dir(), 'readmes')
+    if not os.path.isdir(rd):
+        os.mkdir(rd)
+
+    rd_release = os.path.join(rd, release)
+    if not os.path.isdir(rd_release):
+        os.mkdir(rd_release)
+
+    return rd_release
+
+
 def configured_p():
     """Returns True if gns-deb-diff is configured; False otherwise.
     """
diff --git a/tests/test_gd_diff.py b/tests/test_gd_diff.py
index 0130482..78e10ef 100644
--- a/tests/test_gd_diff.py
+++ b/tests/test_gd_diff.py
@@ -258,6 +258,18 @@ class TestGdDiff(object):
             assert_equal(os.path.isdir(pd), True)
 
 
+    def test_readmes_dir(self):
+        def env(e):
+            return self.test_home
+
+        with mock.patch('os.getenv', new=env):
+            rd_parkes = readmes_dir('parkes')
+            assert_equal(rd_parkes, os.path.join(self.test_home, '.config',
+                                                 'gns-deb-diff', 'readmes',
+                                                 'parkes'))
+            assert_equal(os.path.isdir(rd_parkes), True)
+
+
     def test_configured_p_no(self):
         def env(e):
             return self.test_home