ProgressIndicatorPercent: fix space computation for wide chars, fixes #3027

needs to use swidth() in case there are wide chars (like CJK)
in the left part of the msg (e.g. an archive name).

(cherry picked from commit 3dd14f4855c53b05382d7c80e8ae90eeaef4eb35)

src/borg/helpers/progress.py

@@ -147,10 +147,12 @@ class ProgressIndicatorPercent(ProgressIndicatorBase):
             # truncate the last argument, if no space is available
             if info is not None:
                 if not self.json:
+                    from ..platform import swidth  # avoid circular import
+
                     # no need to truncate if we're not outputting to a terminal
                     terminal_space = get_terminal_size(fallback=(-1, -1))[0]
                     if terminal_space != -1:
-                        space = terminal_space - len(self.msg % tuple([pct] + info[:-1] + ['']))
+                        space = terminal_space - swidth(self.msg % tuple([pct] + info[:-1] + ['']))
                         info[-1] = ellipsis_truncate(info[-1], space)
                 return self.output(self.msg % tuple([pct] + info), justify=False, info=info)
 

src/borg/testsuite/helpers.py

@@ -30,6 +30,7 @@ from ..helpers import popen_with_error_handling
 from ..helpers import dash_open
 from ..helpers import iter_separated
 from ..helpers import eval_escapes
+from ..platform import is_win32, swidth
 
 from . import BaseTestCase, FakeInputs
 
@@ -896,6 +897,29 @@ def test_progress_percentage_sameline(capfd, monkeypatch):
     assert err == ' ' * 4 + '\r'
 
 
+@pytest.mark.skipif(is_win32, reason='no working swidth() implementation on this platform')
+def test_progress_percentage_widechars(capfd, monkeypatch):
+    st = 'スター・トレック'  # 'startrek' :-)
+    assert swidth(st) == 16
+    path = '/カーク船長です。'  # 'Captain Kirk'
+    assert swidth(path) == 17
+    spaces = ' ' * 4  # to avoid usage of '...'
+    width = len('100%') + 1 + swidth(st) + 1 + swidth(path) + swidth(spaces)
+    monkeypatch.setenv('COLUMNS', str(width))
+    monkeypatch.setenv('LINES', '1')
+    pi = ProgressIndicatorPercent(100, step=5, start=0, msg=f'%3.0f%% {st} %s')
+    pi.logger.setLevel('INFO')
+    pi.show(0, info=[path])
+    out, err = capfd.readouterr()
+    assert err == f'  0% {st} {path}{spaces}\r'
+    pi.show(100, info=[path])
+    out, err = capfd.readouterr()
+    assert err == f'100% {st} {path}{spaces}\r'
+    pi.finish()
+    out, err = capfd.readouterr()
+    assert err == ' ' * width + '\r'
+
+
 def test_progress_percentage_step(capfd, monkeypatch):
     # run the test as if it was in a 4x1 terminal
     monkeypatch.setenv('COLUMNS', '4')