framework/core: add fallback to PiglitConfig.safe_get

This is in keeping with the way that configparser.get() works in python3
(although there are some corner case differences since in python3 it
uses keyword only arguments, which don't exist in python2).

Signed-off-by: Dylan Baker <dylanx.c.baker@intel.com>
Reviewed-by: Thomas Wood <thomas.wood@intel.com>

2 files changed, 7 insertions, 3 deletions

diff --git a/framework/core.py b/framework/core.py
index 341652adf..549130bb2 100644
--- a/framework/core.py
+++ b/framework/core.py
@@ -58,7 +58,7 @@ class PiglitConfig(ConfigParser.SafeConfigParser):
         ConfigParser.SafeConfigParser.readfp(self, fp, filename)
         self.filename = os.path.abspath(filename or fp.name)
 
-    def safe_get(self, *args, **kwargs):
+    def safe_get(self, section, option, fallback=None, **kwargs):
         """A version of self.get that doesn't raise NoSectionError or
         NoOptionError.
 
@@ -67,9 +67,9 @@ class PiglitConfig(ConfigParser.SafeConfigParser):
 
         """
         try:
-            return self.get(*args, **kwargs)
+            return self.get(section, option, **kwargs)
         except (ConfigParser.NoOptionError, ConfigParser.NoSectionError):
-            return None
+            return fallback
 
     def required_get(self, section, option, **kwargs):
         """A version fo self.get that raises PiglitFatalError.
diff --git a/framework/tests/core_tests.py b/framework/tests/core_tests.py
index af0933900..9be9c57e3 100644
--- a/framework/tests/core_tests.py
+++ b/framework/tests/core_tests.py
@@ -267,3 +267,7 @@ class TestPiglitConfig(object):
         """core.PiglitConfig: required_get raises PiglitFatalError if the section is missing
         """
         self.conf.required_get('invalid', 'invalid')
+
+    def test_safe_get_fallback(self):
+        """core.PiglitConfig: safe_get returns the value of fallback when the section or option is missing"""
+        nt.eq_(self.conf.safe_get('invalid', 'invalid', fallback='foo'), 'foo')