FAILURE MAP
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FA-83306 / Go territory scoring / Open access

The half glyph is not recognised · case 01

Komi written as 6½ is rejected.

Verified by executionVariant 1 · 8 checks per implementationDownload source bundle ↓JSON ↗

ROOT CAUSE

The suffix test looks for "1/2" rather than the glyph.

VERIFIED REPAIR

Detect the "½" suffix and strip it.

Unsuccessful approach: Detecting the glyph without stripping it leaves a non-digit in the whole part.

Case contract

Input a komi string: optional sign, whole points, and an optional half written ".5"/".0" or "½". A bare half ("½", ".5") is allowed. Return komi in tenths or "invalid".

Why this case matters

Go servers and scoring tools compute this value automatically; a wrong answer changes a game result.

1 / The failure

Exit 1
"""Failure Map reference implementation. Python standard library only."""
import json

N = 1
observations = []
def solve(x):
    s = x.strip()
    neg = s.startswith('-')
    if s[:1] in '+-' and s:
        s = s[1:]
    half = 0
    if s.endswith('1/2'):
        half = 5
        s = s[:-1]
    elif '.' in s:
        s, _, frac = s.partition('.')
        if frac not in ('0', '5'):
            return 'invalid'
        half = int(frac)
    if not s.isdigit():
        if s == '' and half:
            s = '0'
        else:
            return 'invalid'
    v = int(s) * 10 + half
    return -v if neg else v
def check(label, actual, expected):
    observations.append({"check": label, "actual": actual, "expected": expected, "passed": actual == expected})
fixtures = [[['6½', 65], ['-6½', -65], ['7.0', 70], ['6.3', 'invalid'], ['.5', 5], ['', 'invalid'], ['-', 'invalid'], ['abc', 'invalid']], [['abc', 'invalid'], ['5.', 'invalid'], [' 6.5 ', 65], ['-3', -30], ['-7.5', -75], ['0.0', 0], ['+½', 5], ['+½', 5]], [['6.5', 65], ['7', 70], ['-0.5', -5], ['6½', 65], ['-6½', -65], ['6.50', 'invalid'], ['+', 'invalid'], ['+½', 5]], [['0.5', 5], ['6½', 65], ['½', 5], ['½', 5], ['-6½', -65], ['0', 0], ['+5.5', 55], ['7.0', 70]], [['6½', 65], ['-6½', -65], ['-', 'invalid'], ['abc', 'invalid'], ['5.', 'invalid'], [' 6.5 ', 65], ['-3', -30], ['-7.5', -75]]]
for i, (args, expected) in enumerate(fixtures[N-1]):
    check("komi case %d" % i, 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 fixtureActualExpectedOutcome
komi case 0invalid65Failed
komi case 1invalid-65Failed
komi case 27070Passed
komi case 3invalidinvalidPassed
komi case 455Passed
komi case 5invalidinvalidPassed
komi case 6invalidinvalidPassed
komi case 7invalidinvalidPassed

SHA-256 / 9a96ad3df959947a98e8055a9717d97ba71c5ceb7c9b39213fb385471c50364e

2 / The unsuccessful fix

Exit 1
"""Failure Map reference implementation. Python standard library only."""
import json

N = 1
observations = []
def solve(x):
    s = x.strip()
    neg = s.startswith('-')
    if s[:1] in '+-' and s:
        s = s[1:]
    half = 0
    if s.endswith('½'):
        half = 5
    elif '.' in s:
        s, _, frac = s.partition('.')
        if frac not in ('0', '5'):
            return 'invalid'
        half = int(frac)
    if not s.isdigit():
        if s == '' and half:
            s = '0'
        else:
            return 'invalid'
    v = int(s) * 10 + half
    return -v if neg else v
def check(label, actual, expected):
    observations.append({"check": label, "actual": actual, "expected": expected, "passed": actual == expected})
fixtures = [[['6½', 65], ['-6½', -65], ['7.0', 70], ['6.3', 'invalid'], ['.5', 5], ['', 'invalid'], ['-', 'invalid'], ['abc', 'invalid']], [['abc', 'invalid'], ['5.', 'invalid'], [' 6.5 ', 65], ['-3', -30], ['-7.5', -75], ['0.0', 0], ['+½', 5], ['+½', 5]], [['6.5', 65], ['7', 70], ['-0.5', -5], ['6½', 65], ['-6½', -65], ['6.50', 'invalid'], ['+', 'invalid'], ['+½', 5]], [['0.5', 5], ['6½', 65], ['½', 5], ['½', 5], ['-6½', -65], ['0', 0], ['+5.5', 55], ['7.0', 70]], [['6½', 65], ['-6½', -65], ['-', 'invalid'], ['abc', 'invalid'], ['5.', 'invalid'], [' 6.5 ', 65], ['-3', -30], ['-7.5', -75]]]
for i, (args, expected) in enumerate(fixtures[N-1]):
    check("komi case %d" % i, 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 fixtureActualExpectedOutcome
komi case 0invalid65Failed
komi case 1invalid-65Failed
komi case 27070Passed
komi case 3invalidinvalidPassed
komi case 455Passed
komi case 5invalidinvalidPassed
komi case 6invalidinvalidPassed
komi case 7invalidinvalidPassed

SHA-256 / 1a90873b57f7da4821ff9e37425c678022876fa09d2cf3272d9d83fec2a90217

3 / The verified repair

Exit 0
"""Failure Map reference implementation. Python standard library only."""
import json

N = 1
observations = []
def solve(x):
    s = x.strip()
    neg = s.startswith('-')
    if s[:1] in '+-' and s:
        s = s[1:]
    half = 0
    if s.endswith('½'):
        half = 5
        s = s[:-1]
    elif '.' in s:
        s, _, frac = s.partition('.')
        if frac not in ('0', '5'):
            return 'invalid'
        half = int(frac)
    if not s.isdigit():
        if s == '' and half:
            s = '0'
        else:
            return 'invalid'
    v = int(s) * 10 + half
    return -v if neg else v
def check(label, actual, expected):
    observations.append({"check": label, "actual": actual, "expected": expected, "passed": actual == expected})
fixtures = [[['6½', 65], ['-6½', -65], ['7.0', 70], ['6.3', 'invalid'], ['.5', 5], ['', 'invalid'], ['-', 'invalid'], ['abc', 'invalid']], [['abc', 'invalid'], ['5.', 'invalid'], [' 6.5 ', 65], ['-3', -30], ['-7.5', -75], ['0.0', 0], ['+½', 5], ['+½', 5]], [['6.5', 65], ['7', 70], ['-0.5', -5], ['6½', 65], ['-6½', -65], ['6.50', 'invalid'], ['+', 'invalid'], ['+½', 5]], [['0.5', 5], ['6½', 65], ['½', 5], ['½', 5], ['-6½', -65], ['0', 0], ['+5.5', 55], ['7.0', 70]], [['6½', 65], ['-6½', -65], ['-', 'invalid'], ['abc', 'invalid'], ['5.', 'invalid'], [' 6.5 ', 65], ['-3', -30], ['-7.5', -75]]]
for i, (args, expected) in enumerate(fixtures[N-1]):
    check("komi case %d" % i, 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 fixtureActualExpectedOutcome
komi case 06565Passed
komi case 1-65-65Passed
komi case 27070Passed
komi case 3invalidinvalidPassed
komi case 455Passed
komi case 5invalidinvalidPassed
komi case 6invalidinvalidPassed
komi case 7invalidinvalidPassed

SHA-256 / c3531af67ec3f893486e700e64decdbfa106bb8221a98b7f059f90be62e5fc8b

Verification & scope

Small rectangular toy boards given as strings of B, W and dot; a bounded teaching model of one scoring or bookkeeping rule, not a complete rules engine or server implementation. 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 2026-09-29T14:50:20.349834+00:00.

Case digest / 1ffbe6f1024d31d8eced97e3b3284663fb2bdf73ba06498c27cc6f4d97933bf5