FA-75531 / Text diff and three-way merge / Open access

Diffstat histogram: a single insertion is pluralized · case 01

The summary reads "1 insertions(+)".

Verified by executionVariant 1 · 10 checks per implementationDownload source bundle ↓JSON ↗

ROOT CAUSE

The insertion wording is always plural.

THE FAILURE

The insertion wording is always plural.

Unsuccessful approach: Choosing the form from the file count pluralizes by the wrong quantity.

Case contract

Files are [path, added, removed], with None counts for binary files. Each text file prints "path | total +++---"; when the largest total exceeds width, both counts scale by width/max with floor, but a non-zero count keeps at least one mark. Binary files print "path | Bin". The summary counts files and, when non-zero, insertions and deletions with singular/plural wording.

Why this case matters

Diffstat output is how reviewers size a change; scaling and pluralization rules are easy to get subtly wrong.

1 / The failure

Exit 1

"""Failure Map reference implementation. Python standard library only."""
import json

N = 1
observations = []
def solve(files, width):
    mx = max([f[1] + f[2] for f in files if f[1] is not None] + [0])
    lines = []
    ins = dels = changed = 0
    for path, add, rem in files:
        changed += 1
        if add is None:
            lines.append('%s | Bin' % path)
            continue
        ins += add
        dels += rem
        if mx > width:
            pa = add * width // mx
            pr = rem * width // mx
            if add and not pa:
                pa = 1
            if rem and not pr:
                pr = 1
        else:
            pa, pr = add, rem
        lines.append('%s | %d %s' % (path, add + rem, '+' * pa + '-' * pr))
    summary = '%d file%s changed' % (changed, '' if changed == 1 else 's')
    if ins:
        summary += ', %d insertions(+)' % ins
    if dels:
        summary += ', %d deletion%s(-)' % (dels, '' if dels == 1 else 's')
    lines.append(summary)
    return lines
def check(label, actual, expected):
    observations.append({"check": label, "actual": actual, "expected": expected, "passed": actual == expected})
cases = {
    1: [('small changes without scaling', [[['a.txt', 3, 1]], 40], ['a.txt | 4 +++-', '1 file changed, 3 insertions(+), 1 deletion(-)']), ('scaled bar keeps small counts visible', [[['big.c', 200, 0], ['tiny.c', 1, 1]], 20], ['big.c | 200 ++++++++++++++++++++', 'tiny.c | 2 +-', '2 files changed, 201 insertions(+), 1 deletion(-)']), ('binary file', [[['logo.png', None, None], ['x', 2, 0]], 40], ['logo.png | Bin', 'x | 2 ++', '2 files changed, 2 insertions(+)']), ('single insertion grammar', [[['one', 1, 0]], 40], ['one | 1 +', '1 file changed, 1 insertion(+)']), ('only deletions', [[['gone', 0, 5]], 40], ['gone | 5 -----', '1 file changed, 5 deletions(-)']), ('scale uses the largest file', [[['f1', 30, 10], ['f2', 10, 0]], 10], ['f1 | 40 +++++++--', 'f2 | 10 ++', '2 files changed, 40 insertions(+), 10 deletions(-)']), ('several files', [[['p', 1, 0], ['q', 0, 1], ['r', 1, 1]], 5], ['p | 1 +', 'q | 1 -', 'r | 2 +-', '3 files changed, 2 insertions(+), 2 deletions(-)']), ('unscaled wide change', [[['w', 12, 3]], 15], ['w | 15 ++++++++++++---', '1 file changed, 12 insertions(+), 3 deletions(-)']), ('floor not rounding when scaling', [[['r', 7, 0], ['s', 20, 0]], 10], ['r | 7 +++', 's | 20 ++++++++++', '2 files changed, 27 insertions(+)']), ('binary-only change', [[['img1.png', None, None]], 40], ['img1.png | Bin', '1 file changed'])],
    2: [('small changes without scaling', [[['a.txt', 3, 1]], 40], ['a.txt | 4 +++-', '1 file changed, 3 insertions(+), 1 deletion(-)']), ('scaled bar keeps small counts visible', [[['big.c', 200, 0], ['tiny.c', 1, 1]], 20], ['big.c | 200 ++++++++++++++++++++', 'tiny.c | 2 +-', '2 files changed, 201 insertions(+), 1 deletion(-)']), ('binary file', [[['logo.png', None, None], ['x', 2, 0]], 40], ['logo.png | Bin', 'x | 2 ++', '2 files changed, 2 insertions(+)']), ('single insertion grammar', [[['one', 1, 0]], 40], ['one | 1 +', '1 file changed, 1 insertion(+)']), ('only deletions', [[['gone', 0, 6]], 40], ['gone | 6 ------', '1 file changed, 6 deletions(-)']), ('scale uses the largest file', [[['f1', 30, 10], ['f2', 20, 0]], 10], ['f1 | 40 +++++++--', 'f2 | 20 +++++', '2 files changed, 50 insertions(+), 10 deletions(-)']), ('several files', [[['p', 1, 0], ['q', 0, 1], ['r', 2, 2]], 5], ['p | 1 +', 'q | 1 -', 'r | 4 ++--', '3 files changed, 3 insertions(+), 3 deletions(-)']), ('unscaled wide change', [[['w', 12, 3]], 15], ['w | 15 ++++++++++++---', '1 file changed, 12 insertions(+), 3 deletions(-)']), ('floor not rounding when scaling', [[['r', 7, 0], ['s', 20, 0]], 10], ['r | 7 +++', 's | 20 ++++++++++', '2 files changed, 27 insertions(+)']), ('binary-only change', [[['img2.png', None, None]], 40], ['img2.png | Bin', '1 file changed'])],
    3: [('small changes without scaling', [[['a.txt', 3, 1]], 40], ['a.txt | 4 +++-', '1 file changed, 3 insertions(+), 1 deletion(-)']), ('scaled bar keeps small counts visible', [[['big.c', 200, 0], ['tiny.c', 1, 1]], 20], ['big.c | 200 ++++++++++++++++++++', 'tiny.c | 2 +-', '2 files changed, 201 insertions(+), 1 deletion(-)']), ('binary file', [[['logo.png', None, None], ['x', 2, 0]], 40], ['logo.png | Bin', 'x | 2 ++', '2 files changed, 2 insertions(+)']), ('single insertion grammar', [[['one', 1, 0]], 40], ['one | 1 +', '1 file changed, 1 insertion(+)']), ('only deletions', [[['gone', 0, 7]], 40], ['gone | 7 -------', '1 file changed, 7 deletions(-)']), ('scale uses the largest file', [[['f1', 30, 10], ['f2', 30, 0]], 10], ['f1 | 40 +++++++--', 'f2 | 30 +++++++', '2 files changed, 60 insertions(+), 10 deletions(-)']), ('several files', [[['p', 1, 0], ['q', 0, 1], ['r', 3, 3]], 5], ['p | 1 +', 'q | 1 -', 'r | 6 ++--', '3 files changed, 4 insertions(+), 4 deletions(-)']), ('unscaled wide change', [[['w', 12, 3]], 15], ['w | 15 ++++++++++++---', '1 file changed, 12 insertions(+), 3 deletions(-)']), ('floor not rounding when scaling', [[['r', 7, 0], ['s', 20, 0]], 10], ['r | 7 +++', 's | 20 ++++++++++', '2 files changed, 27 insertions(+)']), ('binary-only change', [[['img3.png', None, None]], 40], ['img3.png | Bin', '1 file changed'])],
    4: [('small changes without scaling', [[['a.txt', 3, 1]], 40], ['a.txt | 4 +++-', '1 file changed, 3 insertions(+), 1 deletion(-)']), ('scaled bar keeps small counts visible', [[['big.c', 200, 0], ['tiny.c', 1, 1]], 20], ['big.c | 200 ++++++++++++++++++++', 'tiny.c | 2 +-', '2 files changed, 201 insertions(+), 1 deletion(-)']), ('binary file', [[['logo.png', None, None], ['x', 2, 0]], 40], ['logo.png | Bin', 'x | 2 ++', '2 files changed, 2 insertions(+)']), ('single insertion grammar', [[['one', 1, 0]], 40], ['one | 1 +', '1 file changed, 1 insertion(+)']), ('only deletions', [[['gone', 0, 8]], 40], ['gone | 8 --------', '1 file changed, 8 deletions(-)']), ('scale uses the largest file', [[['f1', 30, 10], ['f2', 40, 0]], 10], ['f1 | 40 +++++++--', 'f2 | 40 ++++++++++', '2 files changed, 70 insertions(+), 10 deletions(-)']), ('several files', [[['p', 1, 0], ['q', 0, 1], ['r', 4, 4]], 5], ['p | 1 +', 'q | 1 -', 'r | 8 ++--', '3 files changed, 5 insertions(+), 5 deletions(-)']), ('unscaled wide change', [[['w', 12, 3]], 15], ['w | 15 ++++++++++++---', '1 file changed, 12 insertions(+), 3 deletions(-)']), ('floor not rounding when scaling', [[['r', 7, 0], ['s', 20, 0]], 10], ['r | 7 +++', 's | 20 ++++++++++', '2 files changed, 27 insertions(+)']), ('binary-only change', [[['img4.png', None, None]], 40], ['img4.png | Bin', '1 file changed'])],
    5: [('small changes without scaling', [[['a.txt', 3, 1]], 40], ['a.txt | 4 +++-', '1 file changed, 3 insertions(+), 1 deletion(-)']), ('scaled bar keeps small counts visible', [[['big.c', 200, 0], ['tiny.c', 1, 1]], 20], ['big.c | 200 ++++++++++++++++++++', 'tiny.c | 2 +-', '2 files changed, 201 insertions(+), 1 deletion(-)']), ('binary file', [[['logo.png', None, None], ['x', 2, 0]], 40], ['logo.png | Bin', 'x | 2 ++', '2 files changed, 2 insertions(+)']), ('single insertion grammar', [[['one', 1, 0]], 40], ['one | 1 +', '1 file changed, 1 insertion(+)']), ('only deletions', [[['gone', 0, 9]], 40], ['gone | 9 ---------', '1 file changed, 9 deletions(-)']), ('scale uses the largest file', [[['f1', 30, 10], ['f2', 50, 0]], 10], ['f1 | 40 ++++++--', 'f2 | 50 ++++++++++', '2 files changed, 80 insertions(+), 10 deletions(-)']), ('several files', [[['p', 1, 0], ['q', 0, 1], ['r', 5, 5]], 5], ['p | 1 +', 'q | 1 -', 'r | 10 ++--', '3 files changed, 6 insertions(+), 6 deletions(-)']), ('unscaled wide change', [[['w', 12, 3]], 15], ['w | 15 ++++++++++++---', '1 file changed, 12 insertions(+), 3 deletions(-)']), ('floor not rounding when scaling', [[['r', 7, 0], ['s', 20, 0]], 10], ['r | 7 +++', 's | 20 ++++++++++', '2 files changed, 27 insertions(+)']), ('binary-only change', [[['img5.png', None, None]], 40], ['img5.png | Bin', '1 file changed'])],
}[N]
for label, args, expected in cases:
    check(label, solve(*args), expected)
print(json.dumps({"observations": observations, "passed": all(x["passed"] for x in observations)}, ensure_ascii=False))
raise SystemExit(0 if all(x["passed"] for x in observations) else 1)

Boundary fixture	Actual	Expected	Outcome
small changes without scaling	`['a.txt \| 4 +++-', '1 file changed, 3 insertions(+), 1 deletion(-)']`	`['a.txt \| 4 +++-', '1 file changed, 3 insertions(+), 1 deletion(-)']`	Passed
scaled bar keeps small counts visible	`['big.c \| 200 ++++++++++++++++++++', 'tiny.c \| 2 +-', '2 files changed, 201 insertions(+), 1 deletion(-)']`	`['big.c \| 200 ++++++++++++++++++++', 'tiny.c \| 2 +-', '2 files changed, 201 insertions(+), 1 deletion(-)']`	Passed
binary file	`['logo.png \| Bin', 'x \| 2 ++', '2 files changed, 2 insertions(+)']`	`['logo.png \| Bin', 'x \| 2 ++', '2 files changed, 2 insertions(+)']`	Passed
single insertion grammar	`['one \| 1 +', '1 file changed, 1 insertions(+)']`	`['one \| 1 +', '1 file changed, 1 insertion(+)']`	Failed
only deletions	`['gone \| 5 -----', '1 file changed, 5 deletions(-)']`	`['gone \| 5 -----', '1 file changed, 5 deletions(-)']`	Passed
scale uses the largest file	`['f1 \| 40 +++++++--', 'f2 \| 10 ++', '2 files changed, 40 insertions(+), 10 deletions(-)']`	`['f1 \| 40 +++++++--', 'f2 \| 10 ++', '2 files changed, 40 insertions(+), 10 deletions(-)']`	Passed
several files	`['p \| 1 +', 'q \| 1 -', 'r \| 2 +-', '3 files changed, 2 insertions(+), 2 deletions(-)']`	`['p \| 1 +', 'q \| 1 -', 'r \| 2 +-', '3 files changed, 2 insertions(+), 2 deletions(-)']`	Passed
unscaled wide change	`['w \| 15 ++++++++++++---', '1 file changed, 12 insertions(+), 3 deletions(-)']`	`['w \| 15 ++++++++++++---', '1 file changed, 12 insertions(+), 3 deletions(-)']`	Passed
floor not rounding when scaling	`['r \| 7 +++', 's \| 20 ++++++++++', '2 files changed, 27 insertions(+)']`	`['r \| 7 +++', 's \| 20 ++++++++++', '2 files changed, 27 insertions(+)']`	Passed
binary-only change	`['img1.png \| Bin', '1 file changed']`	`['img1.png \| Bin', '1 file changed']`	Passed

SHA-256 / 57dc467c77d045d5a90db8bbe7bcf9da688aec8af7c92efeb5e313f876821458

2 / The unsuccessful fix

Exit 1

"""Failure Map reference implementation. Python standard library only."""
import json

N = 1
observations = []
def solve(files, width):
    mx = max([f[1] + f[2] for f in files if f[1] is not None] + [0])
    lines = []
    ins = dels = changed = 0
    for path, add, rem in files:
        changed += 1
        if add is None:
            lines.append('%s | Bin' % path)
            continue
        ins += add
        dels += rem
        if mx > width:
            pa = add * width // mx
            pr = rem * width // mx
            if add and not pa:
                pa = 1
            if rem and not pr:
                pr = 1
        else:
            pa, pr = add, rem
        lines.append('%s | %d %s' % (path, add + rem, '+' * pa + '-' * pr))
    summary = '%d file%s changed' % (changed, '' if changed == 1 else 's')
    if ins:
        summary += ', %d insertion%s(+)' % (ins, '' if changed == 1 else 's')
    if dels:
        summary += ', %d deletion%s(-)' % (dels, '' if dels == 1 else 's')
    lines.append(summary)
    return lines
def check(label, actual, expected):
    observations.append({"check": label, "actual": actual, "expected": expected, "passed": actual == expected})
cases = {
    1: [('small changes without scaling', [[['a.txt', 3, 1]], 40], ['a.txt | 4 +++-', '1 file changed, 3 insertions(+), 1 deletion(-)']), ('scaled bar keeps small counts visible', [[['big.c', 200, 0], ['tiny.c', 1, 1]], 20], ['big.c | 200 ++++++++++++++++++++', 'tiny.c | 2 +-', '2 files changed, 201 insertions(+), 1 deletion(-)']), ('binary file', [[['logo.png', None, None], ['x', 2, 0]], 40], ['logo.png | Bin', 'x | 2 ++', '2 files changed, 2 insertions(+)']), ('single insertion grammar', [[['one', 1, 0]], 40], ['one | 1 +', '1 file changed, 1 insertion(+)']), ('only deletions', [[['gone', 0, 5]], 40], ['gone | 5 -----', '1 file changed, 5 deletions(-)']), ('scale uses the largest file', [[['f1', 30, 10], ['f2', 10, 0]], 10], ['f1 | 40 +++++++--', 'f2 | 10 ++', '2 files changed, 40 insertions(+), 10 deletions(-)']), ('several files', [[['p', 1, 0], ['q', 0, 1], ['r', 1, 1]], 5], ['p | 1 +', 'q | 1 -', 'r | 2 +-', '3 files changed, 2 insertions(+), 2 deletions(-)']), ('unscaled wide change', [[['w', 12, 3]], 15], ['w | 15 ++++++++++++---', '1 file changed, 12 insertions(+), 3 deletions(-)']), ('floor not rounding when scaling', [[['r', 7, 0], ['s', 20, 0]], 10], ['r | 7 +++', 's | 20 ++++++++++', '2 files changed, 27 insertions(+)']), ('binary-only change', [[['img1.png', None, None]], 40], ['img1.png | Bin', '1 file changed'])],
    2: [('small changes without scaling', [[['a.txt', 3, 1]], 40], ['a.txt | 4 +++-', '1 file changed, 3 insertions(+), 1 deletion(-)']), ('scaled bar keeps small counts visible', [[['big.c', 200, 0], ['tiny.c', 1, 1]], 20], ['big.c | 200 ++++++++++++++++++++', 'tiny.c | 2 +-', '2 files changed, 201 insertions(+), 1 deletion(-)']), ('binary file', [[['logo.png', None, None], ['x', 2, 0]], 40], ['logo.png | Bin', 'x | 2 ++', '2 files changed, 2 insertions(+)']), ('single insertion grammar', [[['one', 1, 0]], 40], ['one | 1 +', '1 file changed, 1 insertion(+)']), ('only deletions', [[['gone', 0, 6]], 40], ['gone | 6 ------', '1 file changed, 6 deletions(-)']), ('scale uses the largest file', [[['f1', 30, 10], ['f2', 20, 0]], 10], ['f1 | 40 +++++++--', 'f2 | 20 +++++', '2 files changed, 50 insertions(+), 10 deletions(-)']), ('several files', [[['p', 1, 0], ['q', 0, 1], ['r', 2, 2]], 5], ['p | 1 +', 'q | 1 -', 'r | 4 ++--', '3 files changed, 3 insertions(+), 3 deletions(-)']), ('unscaled wide change', [[['w', 12, 3]], 15], ['w | 15 ++++++++++++---', '1 file changed, 12 insertions(+), 3 deletions(-)']), ('floor not rounding when scaling', [[['r', 7, 0], ['s', 20, 0]], 10], ['r | 7 +++', 's | 20 ++++++++++', '2 files changed, 27 insertions(+)']), ('binary-only change', [[['img2.png', None, None]], 40], ['img2.png | Bin', '1 file changed'])],
    3: [('small changes without scaling', [[['a.txt', 3, 1]], 40], ['a.txt | 4 +++-', '1 file changed, 3 insertions(+), 1 deletion(-)']), ('scaled bar keeps small counts visible', [[['big.c', 200, 0], ['tiny.c', 1, 1]], 20], ['big.c | 200 ++++++++++++++++++++', 'tiny.c | 2 +-', '2 files changed, 201 insertions(+), 1 deletion(-)']), ('binary file', [[['logo.png', None, None], ['x', 2, 0]], 40], ['logo.png | Bin', 'x | 2 ++', '2 files changed, 2 insertions(+)']), ('single insertion grammar', [[['one', 1, 0]], 40], ['one | 1 +', '1 file changed, 1 insertion(+)']), ('only deletions', [[['gone', 0, 7]], 40], ['gone | 7 -------', '1 file changed, 7 deletions(-)']), ('scale uses the largest file', [[['f1', 30, 10], ['f2', 30, 0]], 10], ['f1 | 40 +++++++--', 'f2 | 30 +++++++', '2 files changed, 60 insertions(+), 10 deletions(-)']), ('several files', [[['p', 1, 0], ['q', 0, 1], ['r', 3, 3]], 5], ['p | 1 +', 'q | 1 -', 'r | 6 ++--', '3 files changed, 4 insertions(+), 4 deletions(-)']), ('unscaled wide change', [[['w', 12, 3]], 15], ['w | 15 ++++++++++++---', '1 file changed, 12 insertions(+), 3 deletions(-)']), ('floor not rounding when scaling', [[['r', 7, 0], ['s', 20, 0]], 10], ['r | 7 +++', 's | 20 ++++++++++', '2 files changed, 27 insertions(+)']), ('binary-only change', [[['img3.png', None, None]], 40], ['img3.png | Bin', '1 file changed'])],
    4: [('small changes without scaling', [[['a.txt', 3, 1]], 40], ['a.txt | 4 +++-', '1 file changed, 3 insertions(+), 1 deletion(-)']), ('scaled bar keeps small counts visible', [[['big.c', 200, 0], ['tiny.c', 1, 1]], 20], ['big.c | 200 ++++++++++++++++++++', 'tiny.c | 2 +-', '2 files changed, 201 insertions(+), 1 deletion(-)']), ('binary file', [[['logo.png', None, None], ['x', 2, 0]], 40], ['logo.png | Bin', 'x | 2 ++', '2 files changed, 2 insertions(+)']), ('single insertion grammar', [[['one', 1, 0]], 40], ['one | 1 +', '1 file changed, 1 insertion(+)']), ('only deletions', [[['gone', 0, 8]], 40], ['gone | 8 --------', '1 file changed, 8 deletions(-)']), ('scale uses the largest file', [[['f1', 30, 10], ['f2', 40, 0]], 10], ['f1 | 40 +++++++--', 'f2 | 40 ++++++++++', '2 files changed, 70 insertions(+), 10 deletions(-)']), ('several files', [[['p', 1, 0], ['q', 0, 1], ['r', 4, 4]], 5], ['p | 1 +', 'q | 1 -', 'r | 8 ++--', '3 files changed, 5 insertions(+), 5 deletions(-)']), ('unscaled wide change', [[['w', 12, 3]], 15], ['w | 15 ++++++++++++---', '1 file changed, 12 insertions(+), 3 deletions(-)']), ('floor not rounding when scaling', [[['r', 7, 0], ['s', 20, 0]], 10], ['r | 7 +++', 's | 20 ++++++++++', '2 files changed, 27 insertions(+)']), ('binary-only change', [[['img4.png', None, None]], 40], ['img4.png | Bin', '1 file changed'])],
    5: [('small changes without scaling', [[['a.txt', 3, 1]], 40], ['a.txt | 4 +++-', '1 file changed, 3 insertions(+), 1 deletion(-)']), ('scaled bar keeps small counts visible', [[['big.c', 200, 0], ['tiny.c', 1, 1]], 20], ['big.c | 200 ++++++++++++++++++++', 'tiny.c | 2 +-', '2 files changed, 201 insertions(+), 1 deletion(-)']), ('binary file', [[['logo.png', None, None], ['x', 2, 0]], 40], ['logo.png | Bin', 'x | 2 ++', '2 files changed, 2 insertions(+)']), ('single insertion grammar', [[['one', 1, 0]], 40], ['one | 1 +', '1 file changed, 1 insertion(+)']), ('only deletions', [[['gone', 0, 9]], 40], ['gone | 9 ---------', '1 file changed, 9 deletions(-)']), ('scale uses the largest file', [[['f1', 30, 10], ['f2', 50, 0]], 10], ['f1 | 40 ++++++--', 'f2 | 50 ++++++++++', '2 files changed, 80 insertions(+), 10 deletions(-)']), ('several files', [[['p', 1, 0], ['q', 0, 1], ['r', 5, 5]], 5], ['p | 1 +', 'q | 1 -', 'r | 10 ++--', '3 files changed, 6 insertions(+), 6 deletions(-)']), ('unscaled wide change', [[['w', 12, 3]], 15], ['w | 15 ++++++++++++---', '1 file changed, 12 insertions(+), 3 deletions(-)']), ('floor not rounding when scaling', [[['r', 7, 0], ['s', 20, 0]], 10], ['r | 7 +++', 's | 20 ++++++++++', '2 files changed, 27 insertions(+)']), ('binary-only change', [[['img5.png', None, None]], 40], ['img5.png | Bin', '1 file changed'])],
}[N]
for label, args, expected in cases:
    check(label, solve(*args), expected)
print(json.dumps({"observations": observations, "passed": all(x["passed"] for x in observations)}, ensure_ascii=False))
raise SystemExit(0 if all(x["passed"] for x in observations) else 1)

Boundary fixture	Actual	Expected	Outcome
small changes without scaling	`['a.txt \| 4 +++-', '1 file changed, 3 insertion(+), 1 deletion(-)']`	`['a.txt \| 4 +++-', '1 file changed, 3 insertions(+), 1 deletion(-)']`	Failed
scaled bar keeps small counts visible	`['big.c \| 200 ++++++++++++++++++++', 'tiny.c \| 2 +-', '2 files changed, 201 insertions(+), 1 deletion(-)']`	`['big.c \| 200 ++++++++++++++++++++', 'tiny.c \| 2 +-', '2 files changed, 201 insertions(+), 1 deletion(-)']`	Passed
binary file	`['logo.png \| Bin', 'x \| 2 ++', '2 files changed, 2 insertions(+)']`	`['logo.png \| Bin', 'x \| 2 ++', '2 files changed, 2 insertions(+)']`	Passed
single insertion grammar	`['one \| 1 +', '1 file changed, 1 insertion(+)']`	`['one \| 1 +', '1 file changed, 1 insertion(+)']`	Passed
only deletions	`['gone \| 5 -----', '1 file changed, 5 deletions(-)']`	`['gone \| 5 -----', '1 file changed, 5 deletions(-)']`	Passed
scale uses the largest file	`['f1 \| 40 +++++++--', 'f2 \| 10 ++', '2 files changed, 40 insertions(+), 10 deletions(-)']`	`['f1 \| 40 +++++++--', 'f2 \| 10 ++', '2 files changed, 40 insertions(+), 10 deletions(-)']`	Passed
several files	`['p \| 1 +', 'q \| 1 -', 'r \| 2 +-', '3 files changed, 2 insertions(+), 2 deletions(-)']`	`['p \| 1 +', 'q \| 1 -', 'r \| 2 +-', '3 files changed, 2 insertions(+), 2 deletions(-)']`	Passed
unscaled wide change	`['w \| 15 ++++++++++++---', '1 file changed, 12 insertion(+), 3 deletions(-)']`	`['w \| 15 ++++++++++++---', '1 file changed, 12 insertions(+), 3 deletions(-)']`	Failed
floor not rounding when scaling	`['r \| 7 +++', 's \| 20 ++++++++++', '2 files changed, 27 insertions(+)']`	`['r \| 7 +++', 's \| 20 ++++++++++', '2 files changed, 27 insertions(+)']`	Passed
binary-only change	`['img1.png \| Bin', '1 file changed']`	`['img1.png \| Bin', '1 file changed']`	Passed

SHA-256 / 64a955d4a58862213719d3c7f7a5b5f6675ae8e0ca1cc52c7b1e4d4a7637429c

HELD IN THE MEMBER ARCHIVE

The verified repair and its recorded checks are member-only.

This mechanism has 10 recorded checks per implementation. The open-access tier publishes the failure and the unsuccessful fix; the repaired source that passes every check, and the observations that prove it, are available to members.

Every case sharing this mechanism uses the same contract and the same repair, so this one record is held back for all of them.

Member access is invitation-based. Sign in with your invited account to inspect the repair.

Verification & scope

A deterministic, bounded teaching model of one diff, patch or merge rule with stipulated conventions; it is not a production diff or version-control implementation and makes no claim of conformance to any specific tool. This reproducer isolates one failure mechanism. Results cover the supplied fixtures. Variants within a family share a test contract and should remain grouped when constructing evaluation splits. Related mechanisms with a shared evaluation_group must also remain together; these controlled models are not independent production incidents.

Observations recorded using Python 3.12.14 at 2026-09-29T14:49:07.434775+00:00.

Case digest / 7c472a9420c791a148b64fc9fbd8f995a186b426012ff206f3502a63852b1b0b