unittest helper: Skip if exectuable not found

tests/support.py

@@ -4,6 +4,8 @@ __all__ = [
     'unittest',
 ]
 
+import os
+import subprocess
 from contextlib import contextmanager
 from tempfile import mkdtemp
 from shutil import rmtree
@@ -35,3 +37,21 @@ def get_article(title, slug, content, lang, extra_metadata=None):
     if extra_metadata is not None:
         metadata.update(extra_metadata)
     return Article(content, metadata=metadata)
+
+
+def skipIfNoExecutable(executable, valid_exit_code=1):
+    """Tries to run an executable to make sure it's in the path, Skips the tests
+    if not found.
+    """
+
+    # calling with no params the command should exit with 1
+    with open(os.devnull, 'w') as fnull:
+        try:
+            res = subprocess.call(executable, stdout=fnull, stderr=fnull)
+        except OSError:
+            res = None
+
+    if res != valid_exit_code:
+        return unittest.skip('{0} compiler not found'.format(executable))
+
+    return lambda func: func