Issue 11747: Fix output format for context diffs.
diff --git a/Lib/test/test_difflib.py b/Lib/test/test_difflib.py
index 3533451..310bf99 100644
--- a/Lib/test/test_difflib.py
+++ b/Lib/test/test_difflib.py
@@ -219,6 +219,47 @@
cd = difflib.context_diff(*args, lineterm='')
self.assertEqual(list(cd)[0:2], ["*** Original", "--- Current"])
+ def test_range_format_unified(self):
+ # Per the diff spec at http://www.unix.org/single_unix_specification/
+ spec = '''\
+ Each <range> field shall be of the form:
+ %1d", <beginning line number> if the range contains exactly one line,
+ and:
+ "%1d,%1d", <beginning line number>, <number of lines> otherwise.
+ If a range is empty, its beginning line number shall be the number of
+ the line just before the range, or 0 if the empty range starts the file.
+ '''
+ fmt = difflib._format_range_unified
+ self.assertEqual(fmt(3,3), '3,0')
+ self.assertEqual(fmt(3,4), '4')
+ self.assertEqual(fmt(3,5), '4,2')
+ self.assertEqual(fmt(3,6), '4,3')
+ self.assertEqual(fmt(0,0), '0,0')
+
+ def test_range_format_context(self):
+ # Per the diff spec at http://www.unix.org/single_unix_specification/
+ spec = '''\
+ The range of lines in file1 shall be written in the following format
+ if the range contains two or more lines:
+ "*** %d,%d ****\n", <beginning line number>, <ending line number>
+ and the following format otherwise:
+ "*** %d ****\n", <ending line number>
+ The ending line number of an empty range shall be the number of the preceding line,
+ or 0 if the range is at the start of the file.
+
+ Next, the range of lines in file2 shall be written in the following format
+ if the range contains two or more lines:
+ "--- %d,%d ----\n", <beginning line number>, <ending line number>
+ and the following format otherwise:
+ "--- %d ----\n", <ending line number>
+ '''
+ fmt = difflib._format_range_context
+ self.assertEqual(fmt(3,3), '3')
+ self.assertEqual(fmt(3,4), '4')
+ self.assertEqual(fmt(3,5), '4,5')
+ self.assertEqual(fmt(3,6), '4,6')
+ self.assertEqual(fmt(0,0), '0')
+
def test_main():
difflib.HtmlDiff._default_prefix = 0