FAILURE MAP
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FA-37166 / Table interactions / Open access

Table cell draft lifecycle: noncommit write · case 01

The table noncommit write result violates the stipulated table cell draft lifecycle contract.

Verified by executionVariant 1 · 11 checks per implementationDownload source bundle ↓JSON ↗

ROOT CAUSE

The noncommit write decision uses "if event=='begin':" instead of "if event!='commit':".

VERIFIED REPAIR

Apply the complete noncommit write rule: if event!='commit':.

Unsuccessful approach: The attempted repair "if event not in ('commit','input'):" still loses a required part of the table contract.

Case contract

Cell drafts belong to a stable row-column pair and snapshot the original value and revision. Readonly cells cannot start/input/commit edits, cancellation discards the draft, commits validate required empty strings, reject stale revisions, and suppress unchanged writes.

Why this case matters

An offline table UI model isolates table cell draft lifecycle, including adversarial row/column relationships.

1 / The failure

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

N = 1
observations = []
def solve(row, column, draft, event, value, editable, validator, revision):
    key=(row['id'],column)
    state=dict(draft)
    if event=='begin' and editable: state={'key':key,'base':row[column],'value':row[column],'revision':revision,'error':None}
    if state.get('key')!=key: return {'draft':state,'write':None}
    if event=='input' and editable: state['value']=value
    if event=='cancel': return {'draft':{},'write':None}
    if event=='begin': return {'draft':state,'write':None}
    if not editable: return {'draft':state,'write':None}
    if state['revision']!=revision: state['error']='conflict'; return {'draft':state,'write':None}
    if validator=='required' and state['value']=='': state['error']='required'; return {'draft':state,'write':None}
    if state['value']==state['base']: return {'draft':{},'write':None}
    return {'draft':{},'write':{'row':row['id'],'column':column,'value':state['value'],'expected_revision':revision}}
def check(label, actual, expected):
    observations.append({"check": label, "actual": actual, "expected": expected, "passed": actual == expected})
if N == 1:
    check('begin snapshot', solve({'id':'r','x':1}, 'x', {}, 'begin', 'placeholder', True, 'required', 3), {'draft': {'key': ('r', 'x'), 'base': 1, 'value': 1, 'revision': 3, 'error': None}, 'write': None})
    check('cancel draft', solve({'id':'r','x':1}, 'x', {'key':('r','x'),'base':1,'value':2,'revision':3,'error':None}, 'cancel', None, True, '', 3), {'draft': {}, 'write': None})
    check('wrong column', solve({'id':'r','x':1}, 'x', {'key':('r','y'),'base':1,'value':2,'revision':3,'error':None}, 'commit', None, True, '', 3), {'draft': {'key': ('r', 'y'), 'base': 1, 'value': 2, 'revision': 3, 'error': None}, 'write': None})
    check('readonly input', solve({'id':'r','x':1}, 'x', {'key':('r','x'),'base':1,'value':2,'revision':3,'error':None}, 'input', 4, False, '', 3), {'draft': {'key': ('r', 'x'), 'base': 1, 'value': 2, 'revision': 3, 'error': None}, 'write': None})
    check('stale revision', solve({'id':'r','x':1}, 'x', {'key':('r','x'),'base':1,'value':2,'revision':2,'error':None}, 'commit', None, True, '', 3), {'draft': {'key': ('r', 'x'), 'base': 1, 'value': 2, 'revision': 2, 'error': 'conflict'}, 'write': None})
    check('required empty', solve({'id':'r','x':1}, 'x', {'key':('r','x'),'base':1,'value':'','revision':3,'error':None}, 'commit', None, True, 'required', 3), {'draft': {'key': ('r', 'x'), 'base': 1, 'value': '', 'revision': 3, 'error': 'required'}, 'write': None})
    check('zero valid', solve({'id':'r','x':1}, 'x', {'key':('r','x'),'base':1,'value':0,'revision':3,'error':None}, 'commit', None, True, 'required', 3), {'draft': {}, 'write': {'row': 'r', 'column': 'x', 'value': 0, 'expected_revision': 3}})
    check('unchanged', solve({'id':'r','x':1}, 'x', {'key':('r','x'),'base':1,'value':1,'revision':3,'error':None}, 'commit', None, True, '', 3), {'draft': {}, 'write': None})
    check('readonly commit', solve({'id':'r','x':1}, 'x', {'key':('r','x'),'base':1,'value':2,'revision':3,'error':None}, 'commit', None, False, '', 3), {'draft': {'key': ('r', 'x'), 'base': 1, 'value': 2, 'revision': 3, 'error': None}, 'write': None})
    check('normal input', solve({'id':'r','x':1}, 'x', {'key':('r','x'),'base':1,'value':2,'revision':3,'error':None}, 'input', 5, True, '', 3), {'draft': {'key': ('r', 'x'), 'base': 1, 'value': 5, 'revision': 3, 'error': None}, 'write': None})
    check('readonly begin', solve({'id':'r','x':1}, 'x', {}, 'begin', None, False, '', 3), {'draft': {}, 'write': None})

if N == 2:
    check('begin snapshot', solve({'id':'r','x':2}, 'x', {}, 'begin', 'placeholder', True, 'required', 3), {'draft': {'key': ('r', 'x'), 'base': 2, 'value': 2, 'revision': 3, 'error': None}, 'write': None})
    check('cancel draft', solve({'id':'r','x':1}, 'x', {'key':('r','x'),'base':1,'value':2,'revision':3,'error':None}, 'cancel', None, True, '', 3), {'draft': {}, 'write': None})
    check('wrong column', solve({'id':'r','x':1}, 'x', {'key':('r','y'),'base':1,'value':2,'revision':3,'error':None}, 'commit', None, True, '', 3), {'draft': {'key': ('r', 'y'), 'base': 1, 'value': 2, 'revision': 3, 'error': None}, 'write': None})
    check('readonly input', solve({'id':'r','x':1}, 'x', {'key':('r','x'),'base':1,'value':2,'revision':3,'error':None}, 'input', 4, False, '', 3), {'draft': {'key': ('r', 'x'), 'base': 1, 'value': 2, 'revision': 3, 'error': None}, 'write': None})
    check('stale revision', solve({'id':'r','x':1}, 'x', {'key':('r','x'),'base':1,'value':2,'revision':2,'error':None}, 'commit', None, True, '', 3), {'draft': {'key': ('r', 'x'), 'base': 1, 'value': 2, 'revision': 2, 'error': 'conflict'}, 'write': None})
    check('required empty', solve({'id':'r','x':1}, 'x', {'key':('r','x'),'base':1,'value':'','revision':3,'error':None}, 'commit', None, True, 'required', 3), {'draft': {'key': ('r', 'x'), 'base': 1, 'value': '', 'revision': 3, 'error': 'required'}, 'write': None})
    check('zero valid', solve({'id':'r','x':1}, 'x', {'key':('r','x'),'base':1,'value':0,'revision':3,'error':None}, 'commit', None, True, 'required', 3), {'draft': {}, 'write': {'row': 'r', 'column': 'x', 'value': 0, 'expected_revision': 3}})
    check('unchanged', solve({'id':'r','x':1}, 'x', {'key':('r','x'),'base':1,'value':1,'revision':3,'error':None}, 'commit', None, True, '', 3), {'draft': {}, 'write': None})
    check('readonly commit', solve({'id':'r','x':1}, 'x', {'key':('r','x'),'base':1,'value':2,'revision':3,'error':None}, 'commit', None, False, '', 3), {'draft': {'key': ('r', 'x'), 'base': 1, 'value': 2, 'revision': 3, 'error': None}, 'write': None})
    check('normal input', solve({'id':'r','x':1}, 'x', {'key':('r','x'),'base':1,'value':2,'revision':3,'error':None}, 'input', 5, True, '', 3), {'draft': {'key': ('r', 'x'), 'base': 1, 'value': 5, 'revision': 3, 'error': None}, 'write': None})
    check('readonly begin', solve({'id':'r','x':1}, 'x', {}, 'begin', None, False, '', 3), {'draft': {}, 'write': None})

if N == 3:
    check('begin snapshot', solve({'id':'r','x':3}, 'x', {}, 'begin', 'placeholder', True, 'required', 3), {'draft': {'key': ('r', 'x'), 'base': 3, 'value': 3, 'revision': 3, 'error': None}, 'write': None})
    check('cancel draft', solve({'id':'r','x':1}, 'x', {'key':('r','x'),'base':1,'value':2,'revision':3,'error':None}, 'cancel', None, True, '', 3), {'draft': {}, 'write': None})
    check('wrong column', solve({'id':'r','x':1}, 'x', {'key':('r','y'),'base':1,'value':2,'revision':3,'error':None}, 'commit', None, True, '', 3), {'draft': {'key': ('r', 'y'), 'base': 1, 'value': 2, 'revision': 3, 'error': None}, 'write': None})
    check('readonly input', solve({'id':'r','x':1}, 'x', {'key':('r','x'),'base':1,'value':2,'revision':3,'error':None}, 'input', 4, False, '', 3), {'draft': {'key': ('r', 'x'), 'base': 1, 'value': 2, 'revision': 3, 'error': None}, 'write': None})
    check('stale revision', solve({'id':'r','x':1}, 'x', {'key':('r','x'),'base':1,'value':2,'revision':2,'error':None}, 'commit', None, True, '', 3), {'draft': {'key': ('r', 'x'), 'base': 1, 'value': 2, 'revision': 2, 'error': 'conflict'}, 'write': None})
    check('required empty', solve({'id':'r','x':1}, 'x', {'key':('r','x'),'base':1,'value':'','revision':3,'error':None}, 'commit', None, True, 'required', 3), {'draft': {'key': ('r', 'x'), 'base': 1, 'value': '', 'revision': 3, 'error': 'required'}, 'write': None})
    check('zero valid', solve({'id':'r','x':1}, 'x', {'key':('r','x'),'base':1,'value':0,'revision':3,'error':None}, 'commit', None, True, 'required', 3), {'draft': {}, 'write': {'row': 'r', 'column': 'x', 'value': 0, 'expected_revision': 3}})
    check('unchanged', solve({'id':'r','x':1}, 'x', {'key':('r','x'),'base':1,'value':1,'revision':3,'error':None}, 'commit', None, True, '', 3), {'draft': {}, 'write': None})
    check('readonly commit', solve({'id':'r','x':1}, 'x', {'key':('r','x'),'base':1,'value':2,'revision':3,'error':None}, 'commit', None, False, '', 3), {'draft': {'key': ('r', 'x'), 'base': 1, 'value': 2, 'revision': 3, 'error': None}, 'write': None})
    check('normal input', solve({'id':'r','x':1}, 'x', {'key':('r','x'),'base':1,'value':2,'revision':3,'error':None}, 'input', 5, True, '', 3), {'draft': {'key': ('r', 'x'), 'base': 1, 'value': 5, 'revision': 3, 'error': None}, 'write': None})
    check('readonly begin', solve({'id':'r','x':1}, 'x', {}, 'begin', None, False, '', 3), {'draft': {}, 'write': None})

if N == 4:
    check('begin snapshot', solve({'id':'r','x':4}, 'x', {}, 'begin', 'placeholder', True, 'required', 3), {'draft': {'key': ('r', 'x'), 'base': 4, 'value': 4, 'revision': 3, 'error': None}, 'write': None})
    check('cancel draft', solve({'id':'r','x':1}, 'x', {'key':('r','x'),'base':1,'value':2,'revision':3,'error':None}, 'cancel', None, True, '', 3), {'draft': {}, 'write': None})
    check('wrong column', solve({'id':'r','x':1}, 'x', {'key':('r','y'),'base':1,'value':2,'revision':3,'error':None}, 'commit', None, True, '', 3), {'draft': {'key': ('r', 'y'), 'base': 1, 'value': 2, 'revision': 3, 'error': None}, 'write': None})
    check('readonly input', solve({'id':'r','x':1}, 'x', {'key':('r','x'),'base':1,'value':2,'revision':3,'error':None}, 'input', 4, False, '', 3), {'draft': {'key': ('r', 'x'), 'base': 1, 'value': 2, 'revision': 3, 'error': None}, 'write': None})
    check('stale revision', solve({'id':'r','x':1}, 'x', {'key':('r','x'),'base':1,'value':2,'revision':2,'error':None}, 'commit', None, True, '', 3), {'draft': {'key': ('r', 'x'), 'base': 1, 'value': 2, 'revision': 2, 'error': 'conflict'}, 'write': None})
    check('required empty', solve({'id':'r','x':1}, 'x', {'key':('r','x'),'base':1,'value':'','revision':3,'error':None}, 'commit', None, True, 'required', 3), {'draft': {'key': ('r', 'x'), 'base': 1, 'value': '', 'revision': 3, 'error': 'required'}, 'write': None})
    check('zero valid', solve({'id':'r','x':1}, 'x', {'key':('r','x'),'base':1,'value':0,'revision':3,'error':None}, 'commit', None, True, 'required', 3), {'draft': {}, 'write': {'row': 'r', 'column': 'x', 'value': 0, 'expected_revision': 3}})
    check('unchanged', solve({'id':'r','x':1}, 'x', {'key':('r','x'),'base':1,'value':1,'revision':3,'error':None}, 'commit', None, True, '', 3), {'draft': {}, 'write': None})
    check('readonly commit', solve({'id':'r','x':1}, 'x', {'key':('r','x'),'base':1,'value':2,'revision':3,'error':None}, 'commit', None, False, '', 3), {'draft': {'key': ('r', 'x'), 'base': 1, 'value': 2, 'revision': 3, 'error': None}, 'write': None})
    check('normal input', solve({'id':'r','x':1}, 'x', {'key':('r','x'),'base':1,'value':2,'revision':3,'error':None}, 'input', 5, True, '', 3), {'draft': {'key': ('r', 'x'), 'base': 1, 'value': 5, 'revision': 3, 'error': None}, 'write': None})
    check('readonly begin', solve({'id':'r','x':1}, 'x', {}, 'begin', None, False, '', 3), {'draft': {}, 'write': None})

if N == 5:
    check('begin snapshot', solve({'id':'r','x':5}, 'x', {}, 'begin', 'placeholder', True, 'required', 3), {'draft': {'key': ('r', 'x'), 'base': 5, 'value': 5, 'revision': 3, 'error': None}, 'write': None})
    check('cancel draft', solve({'id':'r','x':1}, 'x', {'key':('r','x'),'base':1,'value':2,'revision':3,'error':None}, 'cancel', None, True, '', 3), {'draft': {}, 'write': None})
    check('wrong column', solve({'id':'r','x':1}, 'x', {'key':('r','y'),'base':1,'value':2,'revision':3,'error':None}, 'commit', None, True, '', 3), {'draft': {'key': ('r', 'y'), 'base': 1, 'value': 2, 'revision': 3, 'error': None}, 'write': None})
    check('readonly input', solve({'id':'r','x':1}, 'x', {'key':('r','x'),'base':1,'value':2,'revision':3,'error':None}, 'input', 4, False, '', 3), {'draft': {'key': ('r', 'x'), 'base': 1, 'value': 2, 'revision': 3, 'error': None}, 'write': None})
    check('stale revision', solve({'id':'r','x':1}, 'x', {'key':('r','x'),'base':1,'value':2,'revision':2,'error':None}, 'commit', None, True, '', 3), {'draft': {'key': ('r', 'x'), 'base': 1, 'value': 2, 'revision': 2, 'error': 'conflict'}, 'write': None})
    check('required empty', solve({'id':'r','x':1}, 'x', {'key':('r','x'),'base':1,'value':'','revision':3,'error':None}, 'commit', None, True, 'required', 3), {'draft': {'key': ('r', 'x'), 'base': 1, 'value': '', 'revision': 3, 'error': 'required'}, 'write': None})
    check('zero valid', solve({'id':'r','x':1}, 'x', {'key':('r','x'),'base':1,'value':0,'revision':3,'error':None}, 'commit', None, True, 'required', 3), {'draft': {}, 'write': {'row': 'r', 'column': 'x', 'value': 0, 'expected_revision': 3}})
    check('unchanged', solve({'id':'r','x':1}, 'x', {'key':('r','x'),'base':1,'value':1,'revision':3,'error':None}, 'commit', None, True, '', 3), {'draft': {}, 'write': None})
    check('readonly commit', solve({'id':'r','x':1}, 'x', {'key':('r','x'),'base':1,'value':2,'revision':3,'error':None}, 'commit', None, False, '', 3), {'draft': {'key': ('r', 'x'), 'base': 1, 'value': 2, 'revision': 3, 'error': None}, 'write': None})
    check('normal input', solve({'id':'r','x':1}, 'x', {'key':('r','x'),'base':1,'value':2,'revision':3,'error':None}, 'input', 5, True, '', 3), {'draft': {'key': ('r', 'x'), 'base': 1, 'value': 5, 'revision': 3, 'error': None}, 'write': None})
    check('readonly begin', solve({'id':'r','x':1}, 'x', {}, 'begin', None, False, '', 3), {'draft': {}, 'write': None})

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
begin snapshot{'draft': {'base': 1, 'error': None, 'key': ['r', 'x'], 'revision': 3, 'value': 1}, 'write': None}{'draft': {'base': 1, 'error': None, 'key': ['r', 'x'], 'revision': 3, 'value': 1}, 'write': None}Passed
cancel draft{'draft': {}, 'write': None}{'draft': {}, 'write': None}Passed
wrong column{'draft': {'base': 1, 'error': None, 'key': ['r', 'y'], 'revision': 3, 'value': 2}, 'write': None}{'draft': {'base': 1, 'error': None, 'key': ['r', 'y'], 'revision': 3, 'value': 2}, 'write': None}Passed
readonly input{'draft': {'base': 1, 'error': None, 'key': ['r', 'x'], 'revision': 3, 'value': 2}, 'write': None}{'draft': {'base': 1, 'error': None, 'key': ['r', 'x'], 'revision': 3, 'value': 2}, 'write': None}Passed
stale revision{'draft': {'base': 1, 'error': 'conflict', 'key': ['r', 'x'], 'revision': 2, 'value': 2}, 'write': None}{'draft': {'base': 1, 'error': 'conflict', 'key': ['r', 'x'], 'revision': 2, 'value': 2}, 'write': None}Passed
required empty{'draft': {'base': 1, 'error': 'required', 'key': ['r', 'x'], 'revision': 3, 'value': ''}, 'write': None}{'draft': {'base': 1, 'error': 'required', 'key': ['r', 'x'], 'revision': 3, 'value': ''}, 'write': None}Passed
zero valid{'draft': {}, 'write': {'column': 'x', 'expected_revision': 3, 'row': 'r', 'value': 0}}{'draft': {}, 'write': {'column': 'x', 'expected_revision': 3, 'row': 'r', 'value': 0}}Passed
unchanged{'draft': {}, 'write': None}{'draft': {}, 'write': None}Passed
readonly commit{'draft': {'base': 1, 'error': None, 'key': ['r', 'x'], 'revision': 3, 'value': 2}, 'write': None}{'draft': {'base': 1, 'error': None, 'key': ['r', 'x'], 'revision': 3, 'value': 2}, 'write': None}Passed
normal input{'draft': {}, 'write': {'column': 'x', 'expected_revision': 3, 'row': 'r', 'value': 5}}{'draft': {'base': 1, 'error': None, 'key': ['r', 'x'], 'revision': 3, 'value': 5}, 'write': None}Failed
readonly begin{'draft': {}, 'write': None}{'draft': {}, 'write': None}Passed

SHA-256 / 830da1f534b8bbf6205e2c9e155f7292a95c2785e62e1f8b8f6bfb5d0465522c

2 / The unsuccessful fix

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

N = 1
observations = []
def solve(row, column, draft, event, value, editable, validator, revision):
    key=(row['id'],column)
    state=dict(draft)
    if event=='begin' and editable: state={'key':key,'base':row[column],'value':row[column],'revision':revision,'error':None}
    if state.get('key')!=key: return {'draft':state,'write':None}
    if event=='input' and editable: state['value']=value
    if event=='cancel': return {'draft':{},'write':None}
    if event not in ('commit','input'): return {'draft':state,'write':None}
    if not editable: return {'draft':state,'write':None}
    if state['revision']!=revision: state['error']='conflict'; return {'draft':state,'write':None}
    if validator=='required' and state['value']=='': state['error']='required'; return {'draft':state,'write':None}
    if state['value']==state['base']: return {'draft':{},'write':None}
    return {'draft':{},'write':{'row':row['id'],'column':column,'value':state['value'],'expected_revision':revision}}
def check(label, actual, expected):
    observations.append({"check": label, "actual": actual, "expected": expected, "passed": actual == expected})
if N == 1:
    check('begin snapshot', solve({'id':'r','x':1}, 'x', {}, 'begin', 'placeholder', True, 'required', 3), {'draft': {'key': ('r', 'x'), 'base': 1, 'value': 1, 'revision': 3, 'error': None}, 'write': None})
    check('cancel draft', solve({'id':'r','x':1}, 'x', {'key':('r','x'),'base':1,'value':2,'revision':3,'error':None}, 'cancel', None, True, '', 3), {'draft': {}, 'write': None})
    check('wrong column', solve({'id':'r','x':1}, 'x', {'key':('r','y'),'base':1,'value':2,'revision':3,'error':None}, 'commit', None, True, '', 3), {'draft': {'key': ('r', 'y'), 'base': 1, 'value': 2, 'revision': 3, 'error': None}, 'write': None})
    check('readonly input', solve({'id':'r','x':1}, 'x', {'key':('r','x'),'base':1,'value':2,'revision':3,'error':None}, 'input', 4, False, '', 3), {'draft': {'key': ('r', 'x'), 'base': 1, 'value': 2, 'revision': 3, 'error': None}, 'write': None})
    check('stale revision', solve({'id':'r','x':1}, 'x', {'key':('r','x'),'base':1,'value':2,'revision':2,'error':None}, 'commit', None, True, '', 3), {'draft': {'key': ('r', 'x'), 'base': 1, 'value': 2, 'revision': 2, 'error': 'conflict'}, 'write': None})
    check('required empty', solve({'id':'r','x':1}, 'x', {'key':('r','x'),'base':1,'value':'','revision':3,'error':None}, 'commit', None, True, 'required', 3), {'draft': {'key': ('r', 'x'), 'base': 1, 'value': '', 'revision': 3, 'error': 'required'}, 'write': None})
    check('zero valid', solve({'id':'r','x':1}, 'x', {'key':('r','x'),'base':1,'value':0,'revision':3,'error':None}, 'commit', None, True, 'required', 3), {'draft': {}, 'write': {'row': 'r', 'column': 'x', 'value': 0, 'expected_revision': 3}})
    check('unchanged', solve({'id':'r','x':1}, 'x', {'key':('r','x'),'base':1,'value':1,'revision':3,'error':None}, 'commit', None, True, '', 3), {'draft': {}, 'write': None})
    check('readonly commit', solve({'id':'r','x':1}, 'x', {'key':('r','x'),'base':1,'value':2,'revision':3,'error':None}, 'commit', None, False, '', 3), {'draft': {'key': ('r', 'x'), 'base': 1, 'value': 2, 'revision': 3, 'error': None}, 'write': None})
    check('normal input', solve({'id':'r','x':1}, 'x', {'key':('r','x'),'base':1,'value':2,'revision':3,'error':None}, 'input', 5, True, '', 3), {'draft': {'key': ('r', 'x'), 'base': 1, 'value': 5, 'revision': 3, 'error': None}, 'write': None})
    check('readonly begin', solve({'id':'r','x':1}, 'x', {}, 'begin', None, False, '', 3), {'draft': {}, 'write': None})

if N == 2:
    check('begin snapshot', solve({'id':'r','x':2}, 'x', {}, 'begin', 'placeholder', True, 'required', 3), {'draft': {'key': ('r', 'x'), 'base': 2, 'value': 2, 'revision': 3, 'error': None}, 'write': None})
    check('cancel draft', solve({'id':'r','x':1}, 'x', {'key':('r','x'),'base':1,'value':2,'revision':3,'error':None}, 'cancel', None, True, '', 3), {'draft': {}, 'write': None})
    check('wrong column', solve({'id':'r','x':1}, 'x', {'key':('r','y'),'base':1,'value':2,'revision':3,'error':None}, 'commit', None, True, '', 3), {'draft': {'key': ('r', 'y'), 'base': 1, 'value': 2, 'revision': 3, 'error': None}, 'write': None})
    check('readonly input', solve({'id':'r','x':1}, 'x', {'key':('r','x'),'base':1,'value':2,'revision':3,'error':None}, 'input', 4, False, '', 3), {'draft': {'key': ('r', 'x'), 'base': 1, 'value': 2, 'revision': 3, 'error': None}, 'write': None})
    check('stale revision', solve({'id':'r','x':1}, 'x', {'key':('r','x'),'base':1,'value':2,'revision':2,'error':None}, 'commit', None, True, '', 3), {'draft': {'key': ('r', 'x'), 'base': 1, 'value': 2, 'revision': 2, 'error': 'conflict'}, 'write': None})
    check('required empty', solve({'id':'r','x':1}, 'x', {'key':('r','x'),'base':1,'value':'','revision':3,'error':None}, 'commit', None, True, 'required', 3), {'draft': {'key': ('r', 'x'), 'base': 1, 'value': '', 'revision': 3, 'error': 'required'}, 'write': None})
    check('zero valid', solve({'id':'r','x':1}, 'x', {'key':('r','x'),'base':1,'value':0,'revision':3,'error':None}, 'commit', None, True, 'required', 3), {'draft': {}, 'write': {'row': 'r', 'column': 'x', 'value': 0, 'expected_revision': 3}})
    check('unchanged', solve({'id':'r','x':1}, 'x', {'key':('r','x'),'base':1,'value':1,'revision':3,'error':None}, 'commit', None, True, '', 3), {'draft': {}, 'write': None})
    check('readonly commit', solve({'id':'r','x':1}, 'x', {'key':('r','x'),'base':1,'value':2,'revision':3,'error':None}, 'commit', None, False, '', 3), {'draft': {'key': ('r', 'x'), 'base': 1, 'value': 2, 'revision': 3, 'error': None}, 'write': None})
    check('normal input', solve({'id':'r','x':1}, 'x', {'key':('r','x'),'base':1,'value':2,'revision':3,'error':None}, 'input', 5, True, '', 3), {'draft': {'key': ('r', 'x'), 'base': 1, 'value': 5, 'revision': 3, 'error': None}, 'write': None})
    check('readonly begin', solve({'id':'r','x':1}, 'x', {}, 'begin', None, False, '', 3), {'draft': {}, 'write': None})

if N == 3:
    check('begin snapshot', solve({'id':'r','x':3}, 'x', {}, 'begin', 'placeholder', True, 'required', 3), {'draft': {'key': ('r', 'x'), 'base': 3, 'value': 3, 'revision': 3, 'error': None}, 'write': None})
    check('cancel draft', solve({'id':'r','x':1}, 'x', {'key':('r','x'),'base':1,'value':2,'revision':3,'error':None}, 'cancel', None, True, '', 3), {'draft': {}, 'write': None})
    check('wrong column', solve({'id':'r','x':1}, 'x', {'key':('r','y'),'base':1,'value':2,'revision':3,'error':None}, 'commit', None, True, '', 3), {'draft': {'key': ('r', 'y'), 'base': 1, 'value': 2, 'revision': 3, 'error': None}, 'write': None})
    check('readonly input', solve({'id':'r','x':1}, 'x', {'key':('r','x'),'base':1,'value':2,'revision':3,'error':None}, 'input', 4, False, '', 3), {'draft': {'key': ('r', 'x'), 'base': 1, 'value': 2, 'revision': 3, 'error': None}, 'write': None})
    check('stale revision', solve({'id':'r','x':1}, 'x', {'key':('r','x'),'base':1,'value':2,'revision':2,'error':None}, 'commit', None, True, '', 3), {'draft': {'key': ('r', 'x'), 'base': 1, 'value': 2, 'revision': 2, 'error': 'conflict'}, 'write': None})
    check('required empty', solve({'id':'r','x':1}, 'x', {'key':('r','x'),'base':1,'value':'','revision':3,'error':None}, 'commit', None, True, 'required', 3), {'draft': {'key': ('r', 'x'), 'base': 1, 'value': '', 'revision': 3, 'error': 'required'}, 'write': None})
    check('zero valid', solve({'id':'r','x':1}, 'x', {'key':('r','x'),'base':1,'value':0,'revision':3,'error':None}, 'commit', None, True, 'required', 3), {'draft': {}, 'write': {'row': 'r', 'column': 'x', 'value': 0, 'expected_revision': 3}})
    check('unchanged', solve({'id':'r','x':1}, 'x', {'key':('r','x'),'base':1,'value':1,'revision':3,'error':None}, 'commit', None, True, '', 3), {'draft': {}, 'write': None})
    check('readonly commit', solve({'id':'r','x':1}, 'x', {'key':('r','x'),'base':1,'value':2,'revision':3,'error':None}, 'commit', None, False, '', 3), {'draft': {'key': ('r', 'x'), 'base': 1, 'value': 2, 'revision': 3, 'error': None}, 'write': None})
    check('normal input', solve({'id':'r','x':1}, 'x', {'key':('r','x'),'base':1,'value':2,'revision':3,'error':None}, 'input', 5, True, '', 3), {'draft': {'key': ('r', 'x'), 'base': 1, 'value': 5, 'revision': 3, 'error': None}, 'write': None})
    check('readonly begin', solve({'id':'r','x':1}, 'x', {}, 'begin', None, False, '', 3), {'draft': {}, 'write': None})

if N == 4:
    check('begin snapshot', solve({'id':'r','x':4}, 'x', {}, 'begin', 'placeholder', True, 'required', 3), {'draft': {'key': ('r', 'x'), 'base': 4, 'value': 4, 'revision': 3, 'error': None}, 'write': None})
    check('cancel draft', solve({'id':'r','x':1}, 'x', {'key':('r','x'),'base':1,'value':2,'revision':3,'error':None}, 'cancel', None, True, '', 3), {'draft': {}, 'write': None})
    check('wrong column', solve({'id':'r','x':1}, 'x', {'key':('r','y'),'base':1,'value':2,'revision':3,'error':None}, 'commit', None, True, '', 3), {'draft': {'key': ('r', 'y'), 'base': 1, 'value': 2, 'revision': 3, 'error': None}, 'write': None})
    check('readonly input', solve({'id':'r','x':1}, 'x', {'key':('r','x'),'base':1,'value':2,'revision':3,'error':None}, 'input', 4, False, '', 3), {'draft': {'key': ('r', 'x'), 'base': 1, 'value': 2, 'revision': 3, 'error': None}, 'write': None})
    check('stale revision', solve({'id':'r','x':1}, 'x', {'key':('r','x'),'base':1,'value':2,'revision':2,'error':None}, 'commit', None, True, '', 3), {'draft': {'key': ('r', 'x'), 'base': 1, 'value': 2, 'revision': 2, 'error': 'conflict'}, 'write': None})
    check('required empty', solve({'id':'r','x':1}, 'x', {'key':('r','x'),'base':1,'value':'','revision':3,'error':None}, 'commit', None, True, 'required', 3), {'draft': {'key': ('r', 'x'), 'base': 1, 'value': '', 'revision': 3, 'error': 'required'}, 'write': None})
    check('zero valid', solve({'id':'r','x':1}, 'x', {'key':('r','x'),'base':1,'value':0,'revision':3,'error':None}, 'commit', None, True, 'required', 3), {'draft': {}, 'write': {'row': 'r', 'column': 'x', 'value': 0, 'expected_revision': 3}})
    check('unchanged', solve({'id':'r','x':1}, 'x', {'key':('r','x'),'base':1,'value':1,'revision':3,'error':None}, 'commit', None, True, '', 3), {'draft': {}, 'write': None})
    check('readonly commit', solve({'id':'r','x':1}, 'x', {'key':('r','x'),'base':1,'value':2,'revision':3,'error':None}, 'commit', None, False, '', 3), {'draft': {'key': ('r', 'x'), 'base': 1, 'value': 2, 'revision': 3, 'error': None}, 'write': None})
    check('normal input', solve({'id':'r','x':1}, 'x', {'key':('r','x'),'base':1,'value':2,'revision':3,'error':None}, 'input', 5, True, '', 3), {'draft': {'key': ('r', 'x'), 'base': 1, 'value': 5, 'revision': 3, 'error': None}, 'write': None})
    check('readonly begin', solve({'id':'r','x':1}, 'x', {}, 'begin', None, False, '', 3), {'draft': {}, 'write': None})

if N == 5:
    check('begin snapshot', solve({'id':'r','x':5}, 'x', {}, 'begin', 'placeholder', True, 'required', 3), {'draft': {'key': ('r', 'x'), 'base': 5, 'value': 5, 'revision': 3, 'error': None}, 'write': None})
    check('cancel draft', solve({'id':'r','x':1}, 'x', {'key':('r','x'),'base':1,'value':2,'revision':3,'error':None}, 'cancel', None, True, '', 3), {'draft': {}, 'write': None})
    check('wrong column', solve({'id':'r','x':1}, 'x', {'key':('r','y'),'base':1,'value':2,'revision':3,'error':None}, 'commit', None, True, '', 3), {'draft': {'key': ('r', 'y'), 'base': 1, 'value': 2, 'revision': 3, 'error': None}, 'write': None})
    check('readonly input', solve({'id':'r','x':1}, 'x', {'key':('r','x'),'base':1,'value':2,'revision':3,'error':None}, 'input', 4, False, '', 3), {'draft': {'key': ('r', 'x'), 'base': 1, 'value': 2, 'revision': 3, 'error': None}, 'write': None})
    check('stale revision', solve({'id':'r','x':1}, 'x', {'key':('r','x'),'base':1,'value':2,'revision':2,'error':None}, 'commit', None, True, '', 3), {'draft': {'key': ('r', 'x'), 'base': 1, 'value': 2, 'revision': 2, 'error': 'conflict'}, 'write': None})
    check('required empty', solve({'id':'r','x':1}, 'x', {'key':('r','x'),'base':1,'value':'','revision':3,'error':None}, 'commit', None, True, 'required', 3), {'draft': {'key': ('r', 'x'), 'base': 1, 'value': '', 'revision': 3, 'error': 'required'}, 'write': None})
    check('zero valid', solve({'id':'r','x':1}, 'x', {'key':('r','x'),'base':1,'value':0,'revision':3,'error':None}, 'commit', None, True, 'required', 3), {'draft': {}, 'write': {'row': 'r', 'column': 'x', 'value': 0, 'expected_revision': 3}})
    check('unchanged', solve({'id':'r','x':1}, 'x', {'key':('r','x'),'base':1,'value':1,'revision':3,'error':None}, 'commit', None, True, '', 3), {'draft': {}, 'write': None})
    check('readonly commit', solve({'id':'r','x':1}, 'x', {'key':('r','x'),'base':1,'value':2,'revision':3,'error':None}, 'commit', None, False, '', 3), {'draft': {'key': ('r', 'x'), 'base': 1, 'value': 2, 'revision': 3, 'error': None}, 'write': None})
    check('normal input', solve({'id':'r','x':1}, 'x', {'key':('r','x'),'base':1,'value':2,'revision':3,'error':None}, 'input', 5, True, '', 3), {'draft': {'key': ('r', 'x'), 'base': 1, 'value': 5, 'revision': 3, 'error': None}, 'write': None})
    check('readonly begin', solve({'id':'r','x':1}, 'x', {}, 'begin', None, False, '', 3), {'draft': {}, 'write': None})

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
begin snapshot{'draft': {'base': 1, 'error': None, 'key': ['r', 'x'], 'revision': 3, 'value': 1}, 'write': None}{'draft': {'base': 1, 'error': None, 'key': ['r', 'x'], 'revision': 3, 'value': 1}, 'write': None}Passed
cancel draft{'draft': {}, 'write': None}{'draft': {}, 'write': None}Passed
wrong column{'draft': {'base': 1, 'error': None, 'key': ['r', 'y'], 'revision': 3, 'value': 2}, 'write': None}{'draft': {'base': 1, 'error': None, 'key': ['r', 'y'], 'revision': 3, 'value': 2}, 'write': None}Passed
readonly input{'draft': {'base': 1, 'error': None, 'key': ['r', 'x'], 'revision': 3, 'value': 2}, 'write': None}{'draft': {'base': 1, 'error': None, 'key': ['r', 'x'], 'revision': 3, 'value': 2}, 'write': None}Passed
stale revision{'draft': {'base': 1, 'error': 'conflict', 'key': ['r', 'x'], 'revision': 2, 'value': 2}, 'write': None}{'draft': {'base': 1, 'error': 'conflict', 'key': ['r', 'x'], 'revision': 2, 'value': 2}, 'write': None}Passed
required empty{'draft': {'base': 1, 'error': 'required', 'key': ['r', 'x'], 'revision': 3, 'value': ''}, 'write': None}{'draft': {'base': 1, 'error': 'required', 'key': ['r', 'x'], 'revision': 3, 'value': ''}, 'write': None}Passed
zero valid{'draft': {}, 'write': {'column': 'x', 'expected_revision': 3, 'row': 'r', 'value': 0}}{'draft': {}, 'write': {'column': 'x', 'expected_revision': 3, 'row': 'r', 'value': 0}}Passed
unchanged{'draft': {}, 'write': None}{'draft': {}, 'write': None}Passed
readonly commit{'draft': {'base': 1, 'error': None, 'key': ['r', 'x'], 'revision': 3, 'value': 2}, 'write': None}{'draft': {'base': 1, 'error': None, 'key': ['r', 'x'], 'revision': 3, 'value': 2}, 'write': None}Passed
normal input{'draft': {}, 'write': {'column': 'x', 'expected_revision': 3, 'row': 'r', 'value': 5}}{'draft': {'base': 1, 'error': None, 'key': ['r', 'x'], 'revision': 3, 'value': 5}, 'write': None}Failed
readonly begin{'draft': {}, 'write': None}{'draft': {}, 'write': None}Passed

SHA-256 / a842aa501116799dede5d322b8f85a643909fa2a00e3edb732c6c29c8a9c20b1

3 / The verified repair

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

N = 1
observations = []
def solve(row, column, draft, event, value, editable, validator, revision):
    key=(row['id'],column)
    state=dict(draft)
    if event=='begin' and editable: state={'key':key,'base':row[column],'value':row[column],'revision':revision,'error':None}
    if state.get('key')!=key: return {'draft':state,'write':None}
    if event=='input' and editable: state['value']=value
    if event=='cancel': return {'draft':{},'write':None}
    if event!='commit': return {'draft':state,'write':None}
    if not editable: return {'draft':state,'write':None}
    if state['revision']!=revision: state['error']='conflict'; return {'draft':state,'write':None}
    if validator=='required' and state['value']=='': state['error']='required'; return {'draft':state,'write':None}
    if state['value']==state['base']: return {'draft':{},'write':None}
    return {'draft':{},'write':{'row':row['id'],'column':column,'value':state['value'],'expected_revision':revision}}
def check(label, actual, expected):
    observations.append({"check": label, "actual": actual, "expected": expected, "passed": actual == expected})
if N == 1:
    check('begin snapshot', solve({'id':'r','x':1}, 'x', {}, 'begin', 'placeholder', True, 'required', 3), {'draft': {'key': ('r', 'x'), 'base': 1, 'value': 1, 'revision': 3, 'error': None}, 'write': None})
    check('cancel draft', solve({'id':'r','x':1}, 'x', {'key':('r','x'),'base':1,'value':2,'revision':3,'error':None}, 'cancel', None, True, '', 3), {'draft': {}, 'write': None})
    check('wrong column', solve({'id':'r','x':1}, 'x', {'key':('r','y'),'base':1,'value':2,'revision':3,'error':None}, 'commit', None, True, '', 3), {'draft': {'key': ('r', 'y'), 'base': 1, 'value': 2, 'revision': 3, 'error': None}, 'write': None})
    check('readonly input', solve({'id':'r','x':1}, 'x', {'key':('r','x'),'base':1,'value':2,'revision':3,'error':None}, 'input', 4, False, '', 3), {'draft': {'key': ('r', 'x'), 'base': 1, 'value': 2, 'revision': 3, 'error': None}, 'write': None})
    check('stale revision', solve({'id':'r','x':1}, 'x', {'key':('r','x'),'base':1,'value':2,'revision':2,'error':None}, 'commit', None, True, '', 3), {'draft': {'key': ('r', 'x'), 'base': 1, 'value': 2, 'revision': 2, 'error': 'conflict'}, 'write': None})
    check('required empty', solve({'id':'r','x':1}, 'x', {'key':('r','x'),'base':1,'value':'','revision':3,'error':None}, 'commit', None, True, 'required', 3), {'draft': {'key': ('r', 'x'), 'base': 1, 'value': '', 'revision': 3, 'error': 'required'}, 'write': None})
    check('zero valid', solve({'id':'r','x':1}, 'x', {'key':('r','x'),'base':1,'value':0,'revision':3,'error':None}, 'commit', None, True, 'required', 3), {'draft': {}, 'write': {'row': 'r', 'column': 'x', 'value': 0, 'expected_revision': 3}})
    check('unchanged', solve({'id':'r','x':1}, 'x', {'key':('r','x'),'base':1,'value':1,'revision':3,'error':None}, 'commit', None, True, '', 3), {'draft': {}, 'write': None})
    check('readonly commit', solve({'id':'r','x':1}, 'x', {'key':('r','x'),'base':1,'value':2,'revision':3,'error':None}, 'commit', None, False, '', 3), {'draft': {'key': ('r', 'x'), 'base': 1, 'value': 2, 'revision': 3, 'error': None}, 'write': None})
    check('normal input', solve({'id':'r','x':1}, 'x', {'key':('r','x'),'base':1,'value':2,'revision':3,'error':None}, 'input', 5, True, '', 3), {'draft': {'key': ('r', 'x'), 'base': 1, 'value': 5, 'revision': 3, 'error': None}, 'write': None})
    check('readonly begin', solve({'id':'r','x':1}, 'x', {}, 'begin', None, False, '', 3), {'draft': {}, 'write': None})

if N == 2:
    check('begin snapshot', solve({'id':'r','x':2}, 'x', {}, 'begin', 'placeholder', True, 'required', 3), {'draft': {'key': ('r', 'x'), 'base': 2, 'value': 2, 'revision': 3, 'error': None}, 'write': None})
    check('cancel draft', solve({'id':'r','x':1}, 'x', {'key':('r','x'),'base':1,'value':2,'revision':3,'error':None}, 'cancel', None, True, '', 3), {'draft': {}, 'write': None})
    check('wrong column', solve({'id':'r','x':1}, 'x', {'key':('r','y'),'base':1,'value':2,'revision':3,'error':None}, 'commit', None, True, '', 3), {'draft': {'key': ('r', 'y'), 'base': 1, 'value': 2, 'revision': 3, 'error': None}, 'write': None})
    check('readonly input', solve({'id':'r','x':1}, 'x', {'key':('r','x'),'base':1,'value':2,'revision':3,'error':None}, 'input', 4, False, '', 3), {'draft': {'key': ('r', 'x'), 'base': 1, 'value': 2, 'revision': 3, 'error': None}, 'write': None})
    check('stale revision', solve({'id':'r','x':1}, 'x', {'key':('r','x'),'base':1,'value':2,'revision':2,'error':None}, 'commit', None, True, '', 3), {'draft': {'key': ('r', 'x'), 'base': 1, 'value': 2, 'revision': 2, 'error': 'conflict'}, 'write': None})
    check('required empty', solve({'id':'r','x':1}, 'x', {'key':('r','x'),'base':1,'value':'','revision':3,'error':None}, 'commit', None, True, 'required', 3), {'draft': {'key': ('r', 'x'), 'base': 1, 'value': '', 'revision': 3, 'error': 'required'}, 'write': None})
    check('zero valid', solve({'id':'r','x':1}, 'x', {'key':('r','x'),'base':1,'value':0,'revision':3,'error':None}, 'commit', None, True, 'required', 3), {'draft': {}, 'write': {'row': 'r', 'column': 'x', 'value': 0, 'expected_revision': 3}})
    check('unchanged', solve({'id':'r','x':1}, 'x', {'key':('r','x'),'base':1,'value':1,'revision':3,'error':None}, 'commit', None, True, '', 3), {'draft': {}, 'write': None})
    check('readonly commit', solve({'id':'r','x':1}, 'x', {'key':('r','x'),'base':1,'value':2,'revision':3,'error':None}, 'commit', None, False, '', 3), {'draft': {'key': ('r', 'x'), 'base': 1, 'value': 2, 'revision': 3, 'error': None}, 'write': None})
    check('normal input', solve({'id':'r','x':1}, 'x', {'key':('r','x'),'base':1,'value':2,'revision':3,'error':None}, 'input', 5, True, '', 3), {'draft': {'key': ('r', 'x'), 'base': 1, 'value': 5, 'revision': 3, 'error': None}, 'write': None})
    check('readonly begin', solve({'id':'r','x':1}, 'x', {}, 'begin', None, False, '', 3), {'draft': {}, 'write': None})

if N == 3:
    check('begin snapshot', solve({'id':'r','x':3}, 'x', {}, 'begin', 'placeholder', True, 'required', 3), {'draft': {'key': ('r', 'x'), 'base': 3, 'value': 3, 'revision': 3, 'error': None}, 'write': None})
    check('cancel draft', solve({'id':'r','x':1}, 'x', {'key':('r','x'),'base':1,'value':2,'revision':3,'error':None}, 'cancel', None, True, '', 3), {'draft': {}, 'write': None})
    check('wrong column', solve({'id':'r','x':1}, 'x', {'key':('r','y'),'base':1,'value':2,'revision':3,'error':None}, 'commit', None, True, '', 3), {'draft': {'key': ('r', 'y'), 'base': 1, 'value': 2, 'revision': 3, 'error': None}, 'write': None})
    check('readonly input', solve({'id':'r','x':1}, 'x', {'key':('r','x'),'base':1,'value':2,'revision':3,'error':None}, 'input', 4, False, '', 3), {'draft': {'key': ('r', 'x'), 'base': 1, 'value': 2, 'revision': 3, 'error': None}, 'write': None})
    check('stale revision', solve({'id':'r','x':1}, 'x', {'key':('r','x'),'base':1,'value':2,'revision':2,'error':None}, 'commit', None, True, '', 3), {'draft': {'key': ('r', 'x'), 'base': 1, 'value': 2, 'revision': 2, 'error': 'conflict'}, 'write': None})
    check('required empty', solve({'id':'r','x':1}, 'x', {'key':('r','x'),'base':1,'value':'','revision':3,'error':None}, 'commit', None, True, 'required', 3), {'draft': {'key': ('r', 'x'), 'base': 1, 'value': '', 'revision': 3, 'error': 'required'}, 'write': None})
    check('zero valid', solve({'id':'r','x':1}, 'x', {'key':('r','x'),'base':1,'value':0,'revision':3,'error':None}, 'commit', None, True, 'required', 3), {'draft': {}, 'write': {'row': 'r', 'column': 'x', 'value': 0, 'expected_revision': 3}})
    check('unchanged', solve({'id':'r','x':1}, 'x', {'key':('r','x'),'base':1,'value':1,'revision':3,'error':None}, 'commit', None, True, '', 3), {'draft': {}, 'write': None})
    check('readonly commit', solve({'id':'r','x':1}, 'x', {'key':('r','x'),'base':1,'value':2,'revision':3,'error':None}, 'commit', None, False, '', 3), {'draft': {'key': ('r', 'x'), 'base': 1, 'value': 2, 'revision': 3, 'error': None}, 'write': None})
    check('normal input', solve({'id':'r','x':1}, 'x', {'key':('r','x'),'base':1,'value':2,'revision':3,'error':None}, 'input', 5, True, '', 3), {'draft': {'key': ('r', 'x'), 'base': 1, 'value': 5, 'revision': 3, 'error': None}, 'write': None})
    check('readonly begin', solve({'id':'r','x':1}, 'x', {}, 'begin', None, False, '', 3), {'draft': {}, 'write': None})

if N == 4:
    check('begin snapshot', solve({'id':'r','x':4}, 'x', {}, 'begin', 'placeholder', True, 'required', 3), {'draft': {'key': ('r', 'x'), 'base': 4, 'value': 4, 'revision': 3, 'error': None}, 'write': None})
    check('cancel draft', solve({'id':'r','x':1}, 'x', {'key':('r','x'),'base':1,'value':2,'revision':3,'error':None}, 'cancel', None, True, '', 3), {'draft': {}, 'write': None})
    check('wrong column', solve({'id':'r','x':1}, 'x', {'key':('r','y'),'base':1,'value':2,'revision':3,'error':None}, 'commit', None, True, '', 3), {'draft': {'key': ('r', 'y'), 'base': 1, 'value': 2, 'revision': 3, 'error': None}, 'write': None})
    check('readonly input', solve({'id':'r','x':1}, 'x', {'key':('r','x'),'base':1,'value':2,'revision':3,'error':None}, 'input', 4, False, '', 3), {'draft': {'key': ('r', 'x'), 'base': 1, 'value': 2, 'revision': 3, 'error': None}, 'write': None})
    check('stale revision', solve({'id':'r','x':1}, 'x', {'key':('r','x'),'base':1,'value':2,'revision':2,'error':None}, 'commit', None, True, '', 3), {'draft': {'key': ('r', 'x'), 'base': 1, 'value': 2, 'revision': 2, 'error': 'conflict'}, 'write': None})
    check('required empty', solve({'id':'r','x':1}, 'x', {'key':('r','x'),'base':1,'value':'','revision':3,'error':None}, 'commit', None, True, 'required', 3), {'draft': {'key': ('r', 'x'), 'base': 1, 'value': '', 'revision': 3, 'error': 'required'}, 'write': None})
    check('zero valid', solve({'id':'r','x':1}, 'x', {'key':('r','x'),'base':1,'value':0,'revision':3,'error':None}, 'commit', None, True, 'required', 3), {'draft': {}, 'write': {'row': 'r', 'column': 'x', 'value': 0, 'expected_revision': 3}})
    check('unchanged', solve({'id':'r','x':1}, 'x', {'key':('r','x'),'base':1,'value':1,'revision':3,'error':None}, 'commit', None, True, '', 3), {'draft': {}, 'write': None})
    check('readonly commit', solve({'id':'r','x':1}, 'x', {'key':('r','x'),'base':1,'value':2,'revision':3,'error':None}, 'commit', None, False, '', 3), {'draft': {'key': ('r', 'x'), 'base': 1, 'value': 2, 'revision': 3, 'error': None}, 'write': None})
    check('normal input', solve({'id':'r','x':1}, 'x', {'key':('r','x'),'base':1,'value':2,'revision':3,'error':None}, 'input', 5, True, '', 3), {'draft': {'key': ('r', 'x'), 'base': 1, 'value': 5, 'revision': 3, 'error': None}, 'write': None})
    check('readonly begin', solve({'id':'r','x':1}, 'x', {}, 'begin', None, False, '', 3), {'draft': {}, 'write': None})

if N == 5:
    check('begin snapshot', solve({'id':'r','x':5}, 'x', {}, 'begin', 'placeholder', True, 'required', 3), {'draft': {'key': ('r', 'x'), 'base': 5, 'value': 5, 'revision': 3, 'error': None}, 'write': None})
    check('cancel draft', solve({'id':'r','x':1}, 'x', {'key':('r','x'),'base':1,'value':2,'revision':3,'error':None}, 'cancel', None, True, '', 3), {'draft': {}, 'write': None})
    check('wrong column', solve({'id':'r','x':1}, 'x', {'key':('r','y'),'base':1,'value':2,'revision':3,'error':None}, 'commit', None, True, '', 3), {'draft': {'key': ('r', 'y'), 'base': 1, 'value': 2, 'revision': 3, 'error': None}, 'write': None})
    check('readonly input', solve({'id':'r','x':1}, 'x', {'key':('r','x'),'base':1,'value':2,'revision':3,'error':None}, 'input', 4, False, '', 3), {'draft': {'key': ('r', 'x'), 'base': 1, 'value': 2, 'revision': 3, 'error': None}, 'write': None})
    check('stale revision', solve({'id':'r','x':1}, 'x', {'key':('r','x'),'base':1,'value':2,'revision':2,'error':None}, 'commit', None, True, '', 3), {'draft': {'key': ('r', 'x'), 'base': 1, 'value': 2, 'revision': 2, 'error': 'conflict'}, 'write': None})
    check('required empty', solve({'id':'r','x':1}, 'x', {'key':('r','x'),'base':1,'value':'','revision':3,'error':None}, 'commit', None, True, 'required', 3), {'draft': {'key': ('r', 'x'), 'base': 1, 'value': '', 'revision': 3, 'error': 'required'}, 'write': None})
    check('zero valid', solve({'id':'r','x':1}, 'x', {'key':('r','x'),'base':1,'value':0,'revision':3,'error':None}, 'commit', None, True, 'required', 3), {'draft': {}, 'write': {'row': 'r', 'column': 'x', 'value': 0, 'expected_revision': 3}})
    check('unchanged', solve({'id':'r','x':1}, 'x', {'key':('r','x'),'base':1,'value':1,'revision':3,'error':None}, 'commit', None, True, '', 3), {'draft': {}, 'write': None})
    check('readonly commit', solve({'id':'r','x':1}, 'x', {'key':('r','x'),'base':1,'value':2,'revision':3,'error':None}, 'commit', None, False, '', 3), {'draft': {'key': ('r', 'x'), 'base': 1, 'value': 2, 'revision': 3, 'error': None}, 'write': None})
    check('normal input', solve({'id':'r','x':1}, 'x', {'key':('r','x'),'base':1,'value':2,'revision':3,'error':None}, 'input', 5, True, '', 3), {'draft': {'key': ('r', 'x'), 'base': 1, 'value': 5, 'revision': 3, 'error': None}, 'write': None})
    check('readonly begin', solve({'id':'r','x':1}, 'x', {}, 'begin', None, False, '', 3), {'draft': {}, 'write': None})

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
begin snapshot{'draft': {'base': 1, 'error': None, 'key': ['r', 'x'], 'revision': 3, 'value': 1}, 'write': None}{'draft': {'base': 1, 'error': None, 'key': ['r', 'x'], 'revision': 3, 'value': 1}, 'write': None}Passed
cancel draft{'draft': {}, 'write': None}{'draft': {}, 'write': None}Passed
wrong column{'draft': {'base': 1, 'error': None, 'key': ['r', 'y'], 'revision': 3, 'value': 2}, 'write': None}{'draft': {'base': 1, 'error': None, 'key': ['r', 'y'], 'revision': 3, 'value': 2}, 'write': None}Passed
readonly input{'draft': {'base': 1, 'error': None, 'key': ['r', 'x'], 'revision': 3, 'value': 2}, 'write': None}{'draft': {'base': 1, 'error': None, 'key': ['r', 'x'], 'revision': 3, 'value': 2}, 'write': None}Passed
stale revision{'draft': {'base': 1, 'error': 'conflict', 'key': ['r', 'x'], 'revision': 2, 'value': 2}, 'write': None}{'draft': {'base': 1, 'error': 'conflict', 'key': ['r', 'x'], 'revision': 2, 'value': 2}, 'write': None}Passed
required empty{'draft': {'base': 1, 'error': 'required', 'key': ['r', 'x'], 'revision': 3, 'value': ''}, 'write': None}{'draft': {'base': 1, 'error': 'required', 'key': ['r', 'x'], 'revision': 3, 'value': ''}, 'write': None}Passed
zero valid{'draft': {}, 'write': {'column': 'x', 'expected_revision': 3, 'row': 'r', 'value': 0}}{'draft': {}, 'write': {'column': 'x', 'expected_revision': 3, 'row': 'r', 'value': 0}}Passed
unchanged{'draft': {}, 'write': None}{'draft': {}, 'write': None}Passed
readonly commit{'draft': {'base': 1, 'error': None, 'key': ['r', 'x'], 'revision': 3, 'value': 2}, 'write': None}{'draft': {'base': 1, 'error': None, 'key': ['r', 'x'], 'revision': 3, 'value': 2}, 'write': None}Passed
normal input{'draft': {'base': 1, 'error': None, 'key': ['r', 'x'], 'revision': 3, 'value': 5}, 'write': None}{'draft': {'base': 1, 'error': None, 'key': ['r', 'x'], 'revision': 3, 'value': 5}, 'write': None}Passed
readonly begin{'draft': {}, 'write': None}{'draft': {}, 'write': None}Passed

SHA-256 / 62e2482d3474b215c9479f83ee8555bbf90ff2e4df0a28a942c5e3bcd0a605c8

Verification & scope

Existing owned drafts contain base, value, revision, and error fields; the column exists in the row. Deterministic offline table UI model; no browser, DOM, framework, or standards conformance is claimed. 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 2026-09-29T14:42:58.615227+00:00.

Case digest / 8149cd981a2d47d7ad364af0a38d26fa1fe49be685775b18828e6bc5e902c0a6