Issue 11747: Fix output format for context diffs.
diff --git a/Lib/difflib.py b/Lib/difflib.py
index 24a58a6..873fc02 100644
--- a/Lib/difflib.py
+++ b/Lib/difflib.py
@@ -1140,6 +1140,21 @@
return ch in ws
+########################################################################
+### Unified Diff
+########################################################################
+
+def _format_range_unified(start, stop):
+ 'Convert range to the "ed" format'
+ # Per the diff spec at http://www.unix.org/single_unix_specification/
+ beginning = start + 1 # lines start numbering with one
+ length = stop - start
+ if length == 1:
+ return '{}'.format(beginning)
+ if not length:
+ beginning -= 1 # empty ranges begin at line just before the range
+ return '{},{}'.format(beginning, length)
+
def unified_diff(a, b, fromfile='', tofile='', fromfiledate='',
tofiledate='', n=3, lineterm='\n'):
r"""
@@ -1160,18 +1175,18 @@
The unidiff format normally has a header for filenames and modification
times. Any or all of these may be specified using strings for
- 'fromfile', 'tofile', 'fromfiledate', and 'tofiledate'. The modification
- times are normally expressed in the format returned by time.ctime().
+ 'fromfile', 'tofile', 'fromfiledate', and 'tofiledate'.
+ The modification times are normally expressed in the ISO 8601 format.
Example:
>>> for line in unified_diff('one two three four'.split(),
... 'zero one tree four'.split(), 'Original', 'Current',
- ... 'Sat Jan 26 23:30:50 1991', 'Fri Jun 06 10:20:52 2003',
+ ... '2005-01-26 23:30:50', '2010-04-02 10:20:52',
... lineterm=''):
- ... print(line)
- --- Original Sat Jan 26 23:30:50 1991
- +++ Current Fri Jun 06 10:20:52 2003
+ ... print(line) # doctest: +NORMALIZE_WHITESPACE
+ --- Original 2005-01-26 23:30:50
+ +++ Current 2010-04-02 10:20:52
@@ -1,4 +1,4 @@
+zero
one
@@ -1184,23 +1199,45 @@
started = False
for group in SequenceMatcher(None,a,b).get_grouped_opcodes(n):
if not started:
- yield '--- %s %s%s' % (fromfile, fromfiledate, lineterm)
- yield '+++ %s %s%s' % (tofile, tofiledate, lineterm)
started = True
- i1, i2, j1, j2 = group[0][1], group[-1][2], group[0][3], group[-1][4]
- yield "@@ -%d,%d +%d,%d @@%s" % (i1+1, i2-i1, j1+1, j2-j1, lineterm)
+ fromdate = '\t{}'.format(fromfiledate) if fromfiledate else ''
+ todate = '\t{}'.format(tofiledate) if tofiledate else ''
+ yield '--- {}{}{}'.format(fromfile, fromdate, lineterm)
+ yield '+++ {}{}{}'.format(tofile, todate, lineterm)
+
+ first, last = group[0], group[-1]
+ file1_range = _format_range_unified(first[1], last[2])
+ file2_range = _format_range_unified(first[3], last[4])
+ yield '@@ -{} +{} @@{}'.format(file1_range, file2_range, lineterm)
+
for tag, i1, i2, j1, j2 in group:
if tag == 'equal':
for line in a[i1:i2]:
yield ' ' + line
continue
- if tag == 'replace' or tag == 'delete':
+ if tag in {'replace', 'delete'}:
for line in a[i1:i2]:
yield '-' + line
- if tag == 'replace' or tag == 'insert':
+ if tag in {'replace', 'insert'}:
for line in b[j1:j2]:
yield '+' + line
+
+########################################################################
+### Context Diff
+########################################################################
+
+def _format_range_context(start, stop):
+ 'Convert range to the "ed" format'
+ # Per the diff spec at http://www.unix.org/single_unix_specification/
+ beginning = start + 1 # lines start numbering with one
+ length = stop - start
+ if not length:
+ beginning -= 1 # empty ranges begin at line just before the range
+ if length <= 1:
+ return '{}'.format(beginning)
+ return '{},{}'.format(beginning, beginning + length - 1)
+
# See http://www.unix.org/single_unix_specification/
def context_diff(a, b, fromfile='', tofile='',
fromfiledate='', tofiledate='', n=3, lineterm='\n'):
@@ -1223,17 +1260,16 @@
The context diff format normally has a header for filenames and
modification times. Any or all of these may be specified using
strings for 'fromfile', 'tofile', 'fromfiledate', and 'tofiledate'.
- The modification times are normally expressed in the format returned
- by time.ctime(). If not specified, the strings default to blanks.
+ The modification times are normally expressed in the ISO 8601 format.
+ If not specified, the strings default to blanks.
Example:
>>> print(''.join(context_diff('one\ntwo\nthree\nfour\n'.splitlines(1),
- ... 'zero\none\ntree\nfour\n'.splitlines(1), 'Original', 'Current',
- ... 'Sat Jan 26 23:30:50 1991', 'Fri Jun 06 10:22:46 2003')),
+ ... 'zero\none\ntree\nfour\n'.splitlines(1), 'Original', 'Current')),
... end="")
- *** Original Sat Jan 26 23:30:50 1991
- --- Current Fri Jun 06 10:22:46 2003
+ *** Original
+ --- Current
***************
*** 1,4 ****
one
@@ -1247,36 +1283,36 @@
four
"""
+ prefix = dict(insert='+ ', delete='- ', replace='! ', equal=' ')
started = False
- prefixmap = {'insert':'+ ', 'delete':'- ', 'replace':'! ', 'equal':' '}
for group in SequenceMatcher(None,a,b).get_grouped_opcodes(n):
if not started:
- yield '*** %s %s%s' % (fromfile, fromfiledate, lineterm)
- yield '--- %s %s%s' % (tofile, tofiledate, lineterm)
started = True
+ fromdate = '\t{}'.format(fromfiledate) if fromfiledate else ''
+ todate = '\t{}'.format(tofiledate) if tofiledate else ''
+ yield '*** {}{}{}'.format(fromfile, fromdate, lineterm)
+ yield '--- {}{}{}'.format(tofile, todate, lineterm)
- yield '***************%s' % (lineterm,)
- if group[-1][2] - group[0][1] >= 2:
- yield '*** %d,%d ****%s' % (group[0][1]+1, group[-1][2], lineterm)
- else:
- yield '*** %d ****%s' % (group[-1][2], lineterm)
- visiblechanges = [e for e in group if e[0] in ('replace', 'delete')]
- if visiblechanges:
+ first, last = group[0], group[-1]
+ yield '***************' + lineterm
+
+ file1_range = _format_range_context(first[1], last[2])
+ yield '*** {} ****{}'.format(file1_range, lineterm)
+
+ if any(tag in {'replace', 'delete'} for tag, _, _, _, _ in group):
for tag, i1, i2, _, _ in group:
if tag != 'insert':
for line in a[i1:i2]:
- yield prefixmap[tag] + line
+ yield prefix[tag] + line
- if group[-1][4] - group[0][3] >= 2:
- yield '--- %d,%d ----%s' % (group[0][3]+1, group[-1][4], lineterm)
- else:
- yield '--- %d ----%s' % (group[-1][4], lineterm)
- visiblechanges = [e for e in group if e[0] in ('replace', 'insert')]
- if visiblechanges:
+ file2_range = _format_range_context(first[3], last[4])
+ yield '--- {} ----{}'.format(file2_range, lineterm)
+
+ if any(tag in {'replace', 'insert'} for tag, _, _, _, _ in group):
for tag, _, _, j1, j2 in group:
if tag != 'delete':
for line in b[j1:j2]:
- yield prefixmap[tag] + line
+ yield prefix[tag] + line
def ndiff(a, b, linejunk=None, charjunk=IS_CHARACTER_JUNK):
r"""