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"""
Tests for clip()'s overtyping (painter) path.
The painter algorithm is used when the text contains cursor movement sequences
(CSI n C/D, backspace, carriage return, HPA) that require column-level tracking
to determine the final visible output. Auto-detection of the overtyping path
happens in clip() via the presence of \\x08, \\r, or horizontal cursor movement
escape sequences, or can be forced with ``overtyping=True``.
These tests codify expected visible results when cursor movement sequences
affect horizontal positions.
"""
# 3rd party
import pytest
# local
from wcwidth import clip
@pytest.mark.parametrize("text,start,end,kwargs,expected", [
# Cursor-right introduces a gap that should be filled with spaces
("hello\x1b[10Cworld", 0, 10, {}, "hello" + " " * 5),
# Clipping just the initial region ignores the later rightward write
("hello\x1b[10Cworld", 0, 5, {}, "hello"),
# Cursor-left overwrites previous characters
("hello\x1b[2DXY", 0, 5, {}, "helXY"),
# Cursor-left overwrites entire visible token
("abc\x1b[3DXY", 0, 5, {}, "XYc"),
# Cursor-left at column 0 (prev_col not > col, no overwrite)
("\x1b[2Dhi", 0, 2, {}, "hi"),
# Cursor-left with no visible tokens emitted
("\x1b[5C\x1b[2Dhi", 5, 7, {}, ""),
# Cursor-left overwrites text, seq tokens preserve column spatial order
("ab\x1b]8;;http://example.com\x07\x1b[2Dcd", 0, 4, {}, "cd\x1b]8;;http://example.com\x07"),
# Cursor-left into wide char twice, second time on empty token triggers i < 0 break
("中\x1b[D\x1b[Da", 0, 4, {}, "a "),
('ab\x1b[5Ccd', 0, 4, {}, 'ab '),
('abcde\x1b[2Df', 0, 6, {}, 'abcfe'),
('hello\x1b[5Dw', 0, 5, {}, 'wello'),
('ab\x1b[10Ccd', 0, 4, {}, 'ab '),
('XY\x1b[Czy', 0, 4, {}, 'XY z'),
('XY\x1b[Czy', 0, 5, {}, 'XY zy'),
('XY\x1b[Czy', 1, 3, {}, 'Y '),
('XY\x1b[Czy', 1, 4, {}, 'Y z'),
('LOL\x1b[5Clol', 0, 12, {}, 'LOL lol'),
('LOL\x1b[5Clol', 1, 11, {}, 'OL lol'),
('LOL\x1b[5Clol', 2, 11, {}, 'L lol'),
('LOL\x1b[5Clol', 3, 11, {}, ' lol'),
('LOL\x1b[5Clol', 4, 11, {}, ' lol'),
('LOL\x1b[5Clol', 5, 11, {}, ' lol'),
('LOL\x1b[5Clol', 6, 11, {}, ' lol'),
('LOL\x1b[5Clol', 7, 11, {}, ' lol'),
('LOL\x1b[5Clol', 8, 11, {}, 'lol'),
('LOL\x1b[5Clol', 9, 11, {}, 'ol'),
# SGR + cursor movement: SGR state update in painter path (line 245)
('\x1b[31mab\x1b[2Dcd', 0, 4, {}, '\x1b[31mcd\x1b[0m'),
# Tab tabsize=0 in painter path (line 272->280 else branch)
('ab\x1b[2D\tcd', 0, 4, {'tabsize': 0}, '\tcd'),
# Zero-width grapheme outside clip window in painter (line 290->301)
('\x1b[2D\u0301hello', 1, 4, {}, 'ell'),
# Wide char partially clipped in painter (lines 298-299)
('ab\x1b[2D中d', 1, 4, {}, ' d'),
# walk_col >= end in painter reconstruction (327->328)
('hello\x1b[2Dxy', 0, 3, {}, 'hel'),
# Hole fillchar in painter reconstruction (345->346)
('\x1b[5Chi', 0, 7, {}, ' hi'),
# Trailing sequences stored at columns after col_limit (352, 354->355, 355->356)
('abc\x1b[2D', 0, 2, {}, 'ab'),
# Bare ESC not part of any sequence, pass through in painter path (239->240)
('a\x1bb\x1b[2Dc', 0, 3, {}, 'c\x1bb'),
# Tab with tabsize>0 in painter; `b` falls at col 4, inside (0,5) (277->284, 278->279, 278->280)
('\x1b[2Da\tb', 0, 5, {'tabsize': 4}, 'a b'),
# propagate_sgr=False in painter path (225->226)
('ab\x1b[2Dcd', 0, 4, {'propagate_sgr': False}, 'cd'),
# Non-SGR sequence before any visible text in painter (225->226 True)
('\x1b]8;;http://example.com\x07ab\x1b[2Dcd', 0, 4, {}, '\x1b]8;;http://example.com\x07cd'),
# Bare ESC at end of text in painter (239->240)
('ab\x1b[2D\x1b', 0, 2, {}, '\x1bab'),
# Wide char overwritten from right side (212 orphan fixup)
('a中\x1b[Db', 0, 4, {}, 'a b'),
# Tab expansion with col+=1 not inside clip window (277->279, 293)
('\x1b[2Ca\tb', 2, 4, {'tabsize': 8}, 'a '),
# CR: carriage return resets column to 0, overwriting earlier cells
('aaa\r\r\rxxx', 0, 4, {}, 'xxx'),
('abc\rXY', 0, 5, {}, 'XYc'),
('hello\rworld', 0, 5, {}, 'world'),
# CR moves back to column 0 then writes within clip window
('abc\rde', 1, 3, {}, 'ec'),
# BS: backspace overwrites previous character
('abc\bde', 0, 5, {}, 'abde'),
('abc\b\bXY', 0, 5, {}, 'aXY'),
('ab\b\b\bXY', 0, 4, {}, 'XY'),
# HPA: horizontal position absolute (CSI n G)
('abc\x1b[GXY', 0, 5, {}, 'XYc'),
('abc\x1b[2GXY', 0, 5, {}, 'aXY'),
('abc\x1b[5GXY', 0, 7, {}, 'abc XY'),
('abc\x1b[5GXY', 0, 5, {}, 'abc X'),
('\x1b[5GXY', 3, 7, {}, ' XY'),
# HPA no-param inside clip window
('abc\x1b[GXY', 1, 4, {}, 'Yc'),
# walk_col >= end with sequences at column == end (line 351)
('\x1b[5C\x1b]8;;http://example.com\x07', 0, 5, {'propagate_sgr': False}, ' \x1b]8;;http://example.com\x07'),
# Trailing sequences past col_limit (line 374)
('\x1b[5C\x1b]8;;http://example.com\x07', 0, 3, {'propagate_sgr': False}, ' \x1b]8;;http://example.com\x07'),
# Lone ESC as first visible thing in painter (captured_style = current_style, line 398)
('\x1b[D\x1b\x1bXy', 0, 3, {}, '\x1b\x1bXy'),
# Hyperlink VISIBLE after captured_style already set
('a\x1b[C\x1b]8;;http://x\x07hi\x1b]8;;\x07', 0, 5, {}, 'a \x1b]8;;http://x\x07hi\x1b]8;;\x07'),
# Tab with tabsize=0 as first visible thing in painter
('\x1b[D\tab', 0, 2, {'tabsize': 0}, '\tab'),
# Zero-width grapheme as first visible thing in painter
('\x1b[D\u0301x', 0, 3, {}, '\u0301x'),
# Generic escape sequence as first visible in painter
('\x1b[D\x1b[Hxy', 0, 3, {}, '\x1b[Hxy'),
])
def test_clip_cursor_sequences_expected_behaviour(text, start, end, kwargs, expected):
"""Verify clip() output matches terminal-visible columns after cursor moves."""
result = clip(text, start, end, **kwargs)
assert repr(result) == repr(expected)
def test_clip_cursor_left_strict_out_of_bounds():
"""Clip() with control_codes='strict' raises on cursor-left beyond string start."""
with pytest.raises(ValueError, match='Cursor left movement'):
clip('a\x1b[5Da', 0, 1, control_codes='strict')
def test_clip_cursor_left_strict_out_of_bounds_painter():
"""Clip() strict-mode raises on cursor-left beyond start in painter path."""
with pytest.raises(ValueError, match='Cursor left movement'):
clip('\x1b[2Dab', 0, 2, control_codes='strict')
def test_clip_cursor_left_out_of_bounds_parse_no_raise():
"""Clip() parse mode silently clamps cursor-left beyond start."""
assert clip('a\x1b[5Da', 0, 1) == 'a'
assert clip('ab\x1b[99Dcd', 0, 4) == 'cd'
def test_clip_strict_cr_allowed():
"""Carriage return is allowed in strict mode (text begins at column 0)."""
assert clip('hello\rworld', 0, 5, control_codes='strict') == 'world'
def test_clip_strict_hpa_allowed():
"""HPA is allowed in strict mode (text begins at column 0)."""
assert clip('abc\x1b[5Gde', 0, 10, control_codes='strict') == 'abc de'
def test_clip_strict_cursor_left_allowed():
"""Cursor-left within bounds is allowed in strict mode."""
assert clip('hello\x1b[2Dxy', 0, 5, control_codes='strict') == 'helxy'
def test_clip_strict_indeterminate_sequence_painter():
"""Clip() strict-mode raises on indeterminate sequence in painter path."""
with pytest.raises(ValueError, match='Indeterminate cursor sequence'):
clip('a\x1b[D\x1b[Hb', 0, 3, control_codes='strict')
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