Rase apply exceptions with hunk context info

Author: Thomas Grainger

.gitignore

@@ -31,6 +31,7 @@ pip-log.txt
 .coverage
 .tox
 nosetests.xml
+.noseids
 
 # Translations
 *.mo

tests/casefiles/diff-unified-bad.diff

@@ -0,0 +1,19 @@
+--- lao	2013-01-05 16:56:19.000000000 -0600
++++ tzu	2013-01-05 16:56:35.000000000 -0600
+@@ -1,7 +1,6 @@
+-The Way that can be told of is not the eternal Way;
+-The name that can be named is not the eternal name.
+ The Nameless is the origin of Heaven and Earth;
+-The Named is the mother of all tings.
++The named is the mother of all things.
++
+ Therefore let there always be non-being,
+   so we may see their subtlety,
+ And let there always be being,
+@@ -9,3 +8,6 @@
+ The two are the same,
+ But after they are produced,
+   they have different names.
++They both may be called deep and profound.
++Deeper and more profound,
++The door of all subtleties!

tests/casefiles/diff-unified-bad2.diff

@@ -0,0 +1,19 @@
+--- lao	2013-01-05 16:56:19.000000000 -0600
++++ tzu	2013-01-05 16:56:35.000000000 -0600
+@@ -1,7 +1,6 @@
+-The Way that can be told of is not the eternal Way;
+-The name that can be named is not the eternal name.
+ The Nameless is the origin of Heaven and Earth;
+-The Named is the mother of all things.
++The named is the mother of all things.
++
+ Therefore let there always be non-being,
+   so we may see their subtlety,
+ And let there always be being,
+@@ -9,3 +8,6 @@
+ The two are te same,
+ But after they are produced,
+   they have different names.
++They both may be called deep and profound.
++Deeper and more profound,
++The door of all subtleties!

tests/test_apply.py

@@ -3,7 +3,7 @@
 import whatthepatch as wtp
 from whatthepatch import exceptions
 
-
+from nose.tools import assert_raises
 import unittest
 
 
@@ -51,6 +51,70 @@ def test_diff_unified(self):
 
         self.assertEqual(new_text, self.tzu)
 
+    def test_diff_unified_bad(self):
+        with open('tests/casefiles/diff-unified-bad.diff') as f:
+            diff_text = f.read()
+
+        diff = next(wtp.parse_patch(diff_text))
+
+        with assert_raises(exceptions.ApplyException) as ec:
+            wtp.apply.apply_diff(diff, self.lao)
+
+        e = ec.exception
+        e_str = str(e)
+        assert 'line 4' in e_str
+        assert 'The Named is the mother of all tings.' in e_str
+        assert 'The Named is the mother of all things.' in e_str
+        assert e.hunk == 1
+
+    def test_diff_unified_bad2(self):
+        with open('tests/casefiles/diff-unified-bad2.diff') as f:
+            diff_text = f.read()
+
+        diff = next(wtp.parse_patch(diff_text))
+
+        with assert_raises(exceptions.ApplyException) as ec:
+            wtp.apply.apply_diff(diff, self.lao)
+
+        e = ec.exception
+        e_str = str(e)
+        assert 'line 9' in e_str
+        assert 'The two are te same,' in e_str
+        assert 'The two are the same,' in e_str
+        assert e.hunk == 2
+
+    def test_diff_unified_bad_backward(self):
+        with open('tests/casefiles/diff-unified-bad2.diff') as f:
+            diff_text = f.read()
+
+        diff = next(wtp.parse_patch(diff_text))
+
+        with assert_raises(exceptions.ApplyException) as ec:
+            wtp.apply.apply_diff(diff, self.tzu)
+
+        e = ec.exception
+        e_str = str(e)
+        assert 'line 1' in e_str
+        assert 'The Way that can be told of is not the eternal Way;' in e_str
+        assert 'The Nameless is the origin of Heaven and Earth;' in e_str
+        assert e.hunk == 1
+
+    def test_diff_unified_bad_empty_source(self):
+        with open('tests/casefiles/diff-unified-bad2.diff') as f:
+            diff_text = f.read()
+
+        diff = next(wtp.parse_patch(diff_text))
+
+        with assert_raises(exceptions.ApplyException) as ec:
+            wtp.apply.apply_diff(diff, '')
+
+        e = ec.exception
+        e_str = str(e)
+        assert 'line 1' in e_str
+        assert 'The Way that can be told of is not the eternal Way;' in e_str
+        assert 'does not exist in source'
+        assert e.hunk == 1
+
     def test_diff_unified_patchutil(self):
         with open('tests/casefiles/diff-unified.diff') as f:
             diff_text = f.read()