From 45b84e4a298d5beea5c9e12093ce4d90c980c7f1 Mon Sep 17 00:00:00 2001
From: David Malcolm <dmalcolm@redhat.com>
Date: Thu, 3 Dec 2009 17:53:02 -0500
Subject: Trap errors when invoking spatch, and bubble up as exceptions;
 introduce hooks for writing unit tests for fixers

---
 fixes/__init__.py | 42 ++++++++++++++++++++++++++++++++++++++++--
 1 file changed, 40 insertions(+), 2 deletions(-)

diff --git a/fixes/__init__.py b/fixes/__init__.py
index 5435e1b..afc578b 100644
--- a/fixes/__init__.py
+++ b/fixes/__init__.py
@@ -6,6 +6,16 @@ class Fix(object):
     def transform(self, string):
         raise NotImplementedError
 
+class CoccinelleError(RuntimeError):
+    def __init__(self, p, args, stderr):
+        self.p = p
+        self.args = args
+        self.stderr = stderr
+
+    def __str__(self):
+        return ('Return code: %s (args: %s)\n --- start of captured stderr ---\n%s--- enf of captured stderr ---\n'
+                % (self.p.returncode, repr(self.args), self.stderr))
+
 class CocciFix(Fix):
     def __init__(self, filename):
         self.filename = filename
@@ -23,11 +33,39 @@ class CocciFix(Fix):
         #print (dst_hn, dst_path)
         os.write(src_hn, string)
 
-        p = Popen(['spatch', '-sp_file', self.get_script_path(), src_path, '-o', dst_path], stdout=PIPE, stderr=PIPE)
-        p.wait()
+        args = ['spatch', '-sp_file', self.get_script_path(), src_path, '-o', dst_path]
+        p = Popen(args, stdout=PIPE, stderr=PIPE)
+        (stdout, stderr) = p.communicate()
+        if p.returncode != 0:
+            raise CoccinelleError(p, args, stderr)
 
         string = open(dst_path, 'r').read()
         os.close(src_hn)
         os.close(dst_hn)
 
         return string
+
+import unittest
+class NonequalStrings(Exception):
+    def __init__(self, actual_result, exp_result):
+        self.actual_result = actual_result
+        self.exp_result = exp_result
+
+    def __str__(self):
+        from difflib import unified_diff
+        result = '\n'
+        for line in unified_diff(self.exp_result.splitlines(),
+                                 self.actual_result.splitlines(), 
+                                 fromfile = 'Expected result',
+                                 tofile = 'Actual result',
+                                 lineterm=''):
+            result += line + '\n'
+        return result
+
+class FixTest(unittest.TestCase):
+    '''Subclass of TestCase for verifying that a Fix is working as expected'''
+    def assertTransformsTo(self, fixer, src, exp_result):
+        actual_result = fixer.transform(src)
+        if actual_result != exp_result:
+            raise NonequalStrings(actual_result, exp_result)
+            
-- 
cgit