FA-38161 / Table interactions / Open access

Asynchronous table cell save acknowledgement: stale server revision · case 01

The table stale server revision result violates the stipulated asynchronous table cell save acknowledgement contract.

Verified by executionVariant 1 · 7 checks per implementationDownload source bundle ↓JSON ↗

ROOT CAUSE

The stale server revision decision uses 'False' instead of "response['revision']<row['revision']".

THE FAILURE

The stale server revision decision uses 'False' instead of "response['revision']<row['revision']".

Unsuccessful approach: The attempted repair "response['revision']<=row['revision']" still loses a required part of the table contract.

Case contract

A save acknowledgement belongs to an exact pending request and row, clears only that pending cell, preserves errors and newer edits, rejects older server revisions, installs canonical server values/revisions, and clears a draft only when the original edit ID still owns it.

Why this case matters

An offline table UI model isolates asynchronous table cell save acknowledgement, 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, pending, response, draft):
    key=(response['row'],response['column'])
    request=pending.get(key)
    if request is None or request['id']!=response['request']: return {'row':row,'pending':sorted(pending.items()),'draft':sorted(draft.items()),'error':None}
    if row['id']!=response['row']: return {'row':row,'pending':sorted(pending.items()),'draft':sorted(draft.items()),'error':None}
    next_pending=dict(pending); next_pending.pop(key)
    if response.get('error') is not None: return {'row':row,'pending':sorted(next_pending.items()),'draft':sorted(draft.items()),'error':response['error']}
    out=dict(row)
    if False: return {'row':out,'pending':sorted(next_pending.items()),'draft':sorted(draft.items()),'error':'stale'}
    out[response['column']]=response['value']; out['revision']=response['revision']
    next_draft=dict(draft)
    if key in next_draft and next_draft[key]['edit_id']==request['edit_id']: next_draft.pop(key)
    return {'row':out,'pending':sorted(next_pending.items()),'draft':sorted(next_draft.items()),'error':None}
def check(label, actual, expected):
    observations.append({"check": label, "actual": actual, "expected": expected, "passed": actual == expected})
if N == 1:
    check('canonical server response', solve({'id':'r','a':'old','revision':3}, {('r','a'):{'id':2,'edit_id':9,'value':' raw '},('r','b'):{'id':3,'edit_id':10,'value':'B'}}, {'row':'r','column':'a','request':2,'revision':8,'value':'raw'+str(1),'warning':'informational'}, {('r','a'):{'edit_id':9,'value':' raw '},('r','b'):{'edit_id':10,'value':'B'}}), {'row': {'id': 'r', 'a': 'raw1', 'revision': 8}, 'pending': [(('r', 'b'), {'id': 3, 'edit_id': 10, 'value': 'B'})], 'draft': [(('r', 'b'), {'edit_id': 10, 'value': 'B'})], 'error': None})
    check('late old request', solve({'id':'r','a':'old','revision':3}, {('r','a'):{'id':2,'edit_id':9,'value':'v'}}, {'row':'r','column':'a','request':1,'revision':4,'value':'old ack'}, {}), {'row': {'id': 'r', 'a': 'old', 'revision': 3}, 'pending': [(('r', 'a'), {'id': 2, 'edit_id': 9, 'value': 'v'})], 'draft': [], 'error': None})
    check('different row', solve({'id':'other','a':'old','revision':3}, {('r','a'):{'id':2,'edit_id':9,'value':'v'}}, {'row':'r','column':'a','request':2,'revision':4,'value':'ack'}, {}), {'row': {'id': 'other', 'a': 'old', 'revision': 3}, 'pending': [(('r', 'a'), {'id': 2, 'edit_id': 9, 'value': 'v'})], 'draft': [], 'error': None})
    check('empty error message', solve({'id':'r','a':'old','revision':3}, {('r','a'):{'id':2,'edit_id':9,'value':'v'}}, {'row':'r','column':'a','request':2,'revision':4,'value':'ack','error':''}, {('r','a'):{'edit_id':9,'value':'v'}}), {'row': {'id': 'r', 'a': 'old', 'revision': 3}, 'pending': [], 'draft': [(('r', 'a'), {'edit_id': 9, 'value': 'v'})], 'error': ''})
    check('stale revision', solve({'id':'r','a':'new','revision':7}, {('r','a'):{'id':2,'edit_id':9,'value':'v'}}, {'row':'r','column':'a','request':2,'revision':6,'value':'ack'}, {}), {'row': {'id': 'r', 'a': 'new', 'revision': 7}, 'pending': [], 'draft': [], 'error': 'stale'})
    check('equal revision allowed', solve({'id':'r','a':'old','revision':3}, {('r','a'):{'id':2,'edit_id':9,'value':'v'}}, {'row':'r','column':'a','request':2,'revision':3,'value':'ack'}, {}), {'row': {'id': 'r', 'a': 'ack', 'revision': 3}, 'pending': [], 'draft': [], 'error': None})
    check('new edit same value', solve({'id':'r','a':'old','revision':3}, {('r','a'):{'id':2,'edit_id':9,'value':'v'}}, {'row':'r','column':'a','request':2,'revision':4,'value':'ack'}, {('r','a'):{'edit_id':10,'value':'v'}}), {'row': {'id': 'r', 'a': 'ack', 'revision': 4}, 'pending': [], 'draft': [(('r', 'a'), {'edit_id': 10, 'value': 'v'})], 'error': None})

if N == 2:
    check('canonical server response', solve({'id':'r','a':'old','revision':3}, {('r','a'):{'id':2,'edit_id':9,'value':' raw '},('r','b'):{'id':3,'edit_id':10,'value':'B'}}, {'row':'r','column':'a','request':2,'revision':8,'value':'raw'+str(2),'warning':'informational'}, {('r','a'):{'edit_id':9,'value':' raw '},('r','b'):{'edit_id':10,'value':'B'}}), {'row': {'id': 'r', 'a': 'raw2', 'revision': 8}, 'pending': [(('r', 'b'), {'id': 3, 'edit_id': 10, 'value': 'B'})], 'draft': [(('r', 'b'), {'edit_id': 10, 'value': 'B'})], 'error': None})
    check('late old request', solve({'id':'r','a':'old','revision':3}, {('r','a'):{'id':2,'edit_id':9,'value':'v'}}, {'row':'r','column':'a','request':1,'revision':4,'value':'old ack'}, {}), {'row': {'id': 'r', 'a': 'old', 'revision': 3}, 'pending': [(('r', 'a'), {'id': 2, 'edit_id': 9, 'value': 'v'})], 'draft': [], 'error': None})
    check('different row', solve({'id':'other','a':'old','revision':3}, {('r','a'):{'id':2,'edit_id':9,'value':'v'}}, {'row':'r','column':'a','request':2,'revision':4,'value':'ack'}, {}), {'row': {'id': 'other', 'a': 'old', 'revision': 3}, 'pending': [(('r', 'a'), {'id': 2, 'edit_id': 9, 'value': 'v'})], 'draft': [], 'error': None})
    check('empty error message', solve({'id':'r','a':'old','revision':3}, {('r','a'):{'id':2,'edit_id':9,'value':'v'}}, {'row':'r','column':'a','request':2,'revision':4,'value':'ack','error':''}, {('r','a'):{'edit_id':9,'value':'v'}}), {'row': {'id': 'r', 'a': 'old', 'revision': 3}, 'pending': [], 'draft': [(('r', 'a'), {'edit_id': 9, 'value': 'v'})], 'error': ''})
    check('stale revision', solve({'id':'r','a':'new','revision':7}, {('r','a'):{'id':2,'edit_id':9,'value':'v'}}, {'row':'r','column':'a','request':2,'revision':6,'value':'ack'}, {}), {'row': {'id': 'r', 'a': 'new', 'revision': 7}, 'pending': [], 'draft': [], 'error': 'stale'})
    check('equal revision allowed', solve({'id':'r','a':'old','revision':3}, {('r','a'):{'id':2,'edit_id':9,'value':'v'}}, {'row':'r','column':'a','request':2,'revision':3,'value':'ack'}, {}), {'row': {'id': 'r', 'a': 'ack', 'revision': 3}, 'pending': [], 'draft': [], 'error': None})
    check('new edit same value', solve({'id':'r','a':'old','revision':3}, {('r','a'):{'id':2,'edit_id':9,'value':'v'}}, {'row':'r','column':'a','request':2,'revision':4,'value':'ack'}, {('r','a'):{'edit_id':10,'value':'v'}}), {'row': {'id': 'r', 'a': 'ack', 'revision': 4}, 'pending': [], 'draft': [(('r', 'a'), {'edit_id': 10, 'value': 'v'})], 'error': None})

if N == 3:
    check('canonical server response', solve({'id':'r','a':'old','revision':3}, {('r','a'):{'id':2,'edit_id':9,'value':' raw '},('r','b'):{'id':3,'edit_id':10,'value':'B'}}, {'row':'r','column':'a','request':2,'revision':8,'value':'raw'+str(3),'warning':'informational'}, {('r','a'):{'edit_id':9,'value':' raw '},('r','b'):{'edit_id':10,'value':'B'}}), {'row': {'id': 'r', 'a': 'raw3', 'revision': 8}, 'pending': [(('r', 'b'), {'id': 3, 'edit_id': 10, 'value': 'B'})], 'draft': [(('r', 'b'), {'edit_id': 10, 'value': 'B'})], 'error': None})
    check('late old request', solve({'id':'r','a':'old','revision':3}, {('r','a'):{'id':2,'edit_id':9,'value':'v'}}, {'row':'r','column':'a','request':1,'revision':4,'value':'old ack'}, {}), {'row': {'id': 'r', 'a': 'old', 'revision': 3}, 'pending': [(('r', 'a'), {'id': 2, 'edit_id': 9, 'value': 'v'})], 'draft': [], 'error': None})
    check('different row', solve({'id':'other','a':'old','revision':3}, {('r','a'):{'id':2,'edit_id':9,'value':'v'}}, {'row':'r','column':'a','request':2,'revision':4,'value':'ack'}, {}), {'row': {'id': 'other', 'a': 'old', 'revision': 3}, 'pending': [(('r', 'a'), {'id': 2, 'edit_id': 9, 'value': 'v'})], 'draft': [], 'error': None})
    check('empty error message', solve({'id':'r','a':'old','revision':3}, {('r','a'):{'id':2,'edit_id':9,'value':'v'}}, {'row':'r','column':'a','request':2,'revision':4,'value':'ack','error':''}, {('r','a'):{'edit_id':9,'value':'v'}}), {'row': {'id': 'r', 'a': 'old', 'revision': 3}, 'pending': [], 'draft': [(('r', 'a'), {'edit_id': 9, 'value': 'v'})], 'error': ''})
    check('stale revision', solve({'id':'r','a':'new','revision':7}, {('r','a'):{'id':2,'edit_id':9,'value':'v'}}, {'row':'r','column':'a','request':2,'revision':6,'value':'ack'}, {}), {'row': {'id': 'r', 'a': 'new', 'revision': 7}, 'pending': [], 'draft': [], 'error': 'stale'})
    check('equal revision allowed', solve({'id':'r','a':'old','revision':3}, {('r','a'):{'id':2,'edit_id':9,'value':'v'}}, {'row':'r','column':'a','request':2,'revision':3,'value':'ack'}, {}), {'row': {'id': 'r', 'a': 'ack', 'revision': 3}, 'pending': [], 'draft': [], 'error': None})
    check('new edit same value', solve({'id':'r','a':'old','revision':3}, {('r','a'):{'id':2,'edit_id':9,'value':'v'}}, {'row':'r','column':'a','request':2,'revision':4,'value':'ack'}, {('r','a'):{'edit_id':10,'value':'v'}}), {'row': {'id': 'r', 'a': 'ack', 'revision': 4}, 'pending': [], 'draft': [(('r', 'a'), {'edit_id': 10, 'value': 'v'})], 'error': None})

if N == 4:
    check('canonical server response', solve({'id':'r','a':'old','revision':3}, {('r','a'):{'id':2,'edit_id':9,'value':' raw '},('r','b'):{'id':3,'edit_id':10,'value':'B'}}, {'row':'r','column':'a','request':2,'revision':8,'value':'raw'+str(4),'warning':'informational'}, {('r','a'):{'edit_id':9,'value':' raw '},('r','b'):{'edit_id':10,'value':'B'}}), {'row': {'id': 'r', 'a': 'raw4', 'revision': 8}, 'pending': [(('r', 'b'), {'id': 3, 'edit_id': 10, 'value': 'B'})], 'draft': [(('r', 'b'), {'edit_id': 10, 'value': 'B'})], 'error': None})
    check('late old request', solve({'id':'r','a':'old','revision':3}, {('r','a'):{'id':2,'edit_id':9,'value':'v'}}, {'row':'r','column':'a','request':1,'revision':4,'value':'old ack'}, {}), {'row': {'id': 'r', 'a': 'old', 'revision': 3}, 'pending': [(('r', 'a'), {'id': 2, 'edit_id': 9, 'value': 'v'})], 'draft': [], 'error': None})
    check('different row', solve({'id':'other','a':'old','revision':3}, {('r','a'):{'id':2,'edit_id':9,'value':'v'}}, {'row':'r','column':'a','request':2,'revision':4,'value':'ack'}, {}), {'row': {'id': 'other', 'a': 'old', 'revision': 3}, 'pending': [(('r', 'a'), {'id': 2, 'edit_id': 9, 'value': 'v'})], 'draft': [], 'error': None})
    check('empty error message', solve({'id':'r','a':'old','revision':3}, {('r','a'):{'id':2,'edit_id':9,'value':'v'}}, {'row':'r','column':'a','request':2,'revision':4,'value':'ack','error':''}, {('r','a'):{'edit_id':9,'value':'v'}}), {'row': {'id': 'r', 'a': 'old', 'revision': 3}, 'pending': [], 'draft': [(('r', 'a'), {'edit_id': 9, 'value': 'v'})], 'error': ''})
    check('stale revision', solve({'id':'r','a':'new','revision':7}, {('r','a'):{'id':2,'edit_id':9,'value':'v'}}, {'row':'r','column':'a','request':2,'revision':6,'value':'ack'}, {}), {'row': {'id': 'r', 'a': 'new', 'revision': 7}, 'pending': [], 'draft': [], 'error': 'stale'})
    check('equal revision allowed', solve({'id':'r','a':'old','revision':3}, {('r','a'):{'id':2,'edit_id':9,'value':'v'}}, {'row':'r','column':'a','request':2,'revision':3,'value':'ack'}, {}), {'row': {'id': 'r', 'a': 'ack', 'revision': 3}, 'pending': [], 'draft': [], 'error': None})
    check('new edit same value', solve({'id':'r','a':'old','revision':3}, {('r','a'):{'id':2,'edit_id':9,'value':'v'}}, {'row':'r','column':'a','request':2,'revision':4,'value':'ack'}, {('r','a'):{'edit_id':10,'value':'v'}}), {'row': {'id': 'r', 'a': 'ack', 'revision': 4}, 'pending': [], 'draft': [(('r', 'a'), {'edit_id': 10, 'value': 'v'})], 'error': None})

if N == 5:
    check('canonical server response', solve({'id':'r','a':'old','revision':3}, {('r','a'):{'id':2,'edit_id':9,'value':' raw '},('r','b'):{'id':3,'edit_id':10,'value':'B'}}, {'row':'r','column':'a','request':2,'revision':8,'value':'raw'+str(5),'warning':'informational'}, {('r','a'):{'edit_id':9,'value':' raw '},('r','b'):{'edit_id':10,'value':'B'}}), {'row': {'id': 'r', 'a': 'raw5', 'revision': 8}, 'pending': [(('r', 'b'), {'id': 3, 'edit_id': 10, 'value': 'B'})], 'draft': [(('r', 'b'), {'edit_id': 10, 'value': 'B'})], 'error': None})
    check('late old request', solve({'id':'r','a':'old','revision':3}, {('r','a'):{'id':2,'edit_id':9,'value':'v'}}, {'row':'r','column':'a','request':1,'revision':4,'value':'old ack'}, {}), {'row': {'id': 'r', 'a': 'old', 'revision': 3}, 'pending': [(('r', 'a'), {'id': 2, 'edit_id': 9, 'value': 'v'})], 'draft': [], 'error': None})
    check('different row', solve({'id':'other','a':'old','revision':3}, {('r','a'):{'id':2,'edit_id':9,'value':'v'}}, {'row':'r','column':'a','request':2,'revision':4,'value':'ack'}, {}), {'row': {'id': 'other', 'a': 'old', 'revision': 3}, 'pending': [(('r', 'a'), {'id': 2, 'edit_id': 9, 'value': 'v'})], 'draft': [], 'error': None})
    check('empty error message', solve({'id':'r','a':'old','revision':3}, {('r','a'):{'id':2,'edit_id':9,'value':'v'}}, {'row':'r','column':'a','request':2,'revision':4,'value':'ack','error':''}, {('r','a'):{'edit_id':9,'value':'v'}}), {'row': {'id': 'r', 'a': 'old', 'revision': 3}, 'pending': [], 'draft': [(('r', 'a'), {'edit_id': 9, 'value': 'v'})], 'error': ''})
    check('stale revision', solve({'id':'r','a':'new','revision':7}, {('r','a'):{'id':2,'edit_id':9,'value':'v'}}, {'row':'r','column':'a','request':2,'revision':6,'value':'ack'}, {}), {'row': {'id': 'r', 'a': 'new', 'revision': 7}, 'pending': [], 'draft': [], 'error': 'stale'})
    check('equal revision allowed', solve({'id':'r','a':'old','revision':3}, {('r','a'):{'id':2,'edit_id':9,'value':'v'}}, {'row':'r','column':'a','request':2,'revision':3,'value':'ack'}, {}), {'row': {'id': 'r', 'a': 'ack', 'revision': 3}, 'pending': [], 'draft': [], 'error': None})
    check('new edit same value', solve({'id':'r','a':'old','revision':3}, {('r','a'):{'id':2,'edit_id':9,'value':'v'}}, {'row':'r','column':'a','request':2,'revision':4,'value':'ack'}, {('r','a'):{'edit_id':10,'value':'v'}}), {'row': {'id': 'r', 'a': 'ack', 'revision': 4}, 'pending': [], 'draft': [(('r', 'a'), {'edit_id': 10, 'value': 'v'})], 'error': 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 fixture	Actual	Expected	Outcome
canonical server response	`{'draft': [[['r', 'b'], {'edit_id': 10, 'value': 'B'}]], 'error': None, 'pending': [[['r', 'b'], {'edit_id': 10, 'id': 3, 'value': 'B'}]], 'row': {'a': 'raw1', 'id': 'r', 'revision': 8}}`	`{'draft': [[['r', 'b'], {'edit_id': 10, 'value': 'B'}]], 'error': None, 'pending': [[['r', 'b'], {'edit_id': 10, 'id': 3, 'value': 'B'}]], 'row': {'a': 'raw1', 'id': 'r', 'revision': 8}}`	Passed
late old request	`{'draft': [], 'error': None, 'pending': [[['r', 'a'], {'edit_id': 9, 'id': 2, 'value': 'v'}]], 'row': {'a': 'old', 'id': 'r', 'revision': 3}}`	`{'draft': [], 'error': None, 'pending': [[['r', 'a'], {'edit_id': 9, 'id': 2, 'value': 'v'}]], 'row': {'a': 'old', 'id': 'r', 'revision': 3}}`	Passed
different row	`{'draft': [], 'error': None, 'pending': [[['r', 'a'], {'edit_id': 9, 'id': 2, 'value': 'v'}]], 'row': {'a': 'old', 'id': 'other', 'revision': 3}}`	`{'draft': [], 'error': None, 'pending': [[['r', 'a'], {'edit_id': 9, 'id': 2, 'value': 'v'}]], 'row': {'a': 'old', 'id': 'other', 'revision': 3}}`	Passed
empty error message	`{'draft': [[['r', 'a'], {'edit_id': 9, 'value': 'v'}]], 'error': '', 'pending': [], 'row': {'a': 'old', 'id': 'r', 'revision': 3}}`	`{'draft': [[['r', 'a'], {'edit_id': 9, 'value': 'v'}]], 'error': '', 'pending': [], 'row': {'a': 'old', 'id': 'r', 'revision': 3}}`	Passed
stale revision	`{'draft': [], 'error': None, 'pending': [], 'row': {'a': 'ack', 'id': 'r', 'revision': 6}}`	`{'draft': [], 'error': 'stale', 'pending': [], 'row': {'a': 'new', 'id': 'r', 'revision': 7}}`	Failed
equal revision allowed	`{'draft': [], 'error': None, 'pending': [], 'row': {'a': 'ack', 'id': 'r', 'revision': 3}}`	`{'draft': [], 'error': None, 'pending': [], 'row': {'a': 'ack', 'id': 'r', 'revision': 3}}`	Passed
new edit same value	`{'draft': [[['r', 'a'], {'edit_id': 10, 'value': 'v'}]], 'error': None, 'pending': [], 'row': {'a': 'ack', 'id': 'r', 'revision': 4}}`	`{'draft': [[['r', 'a'], {'edit_id': 10, 'value': 'v'}]], 'error': None, 'pending': [], 'row': {'a': 'ack', 'id': 'r', 'revision': 4}}`	Passed

SHA-256 / ac1c015908dc02da56da65562d420a5d4712296d743ba013312bc9889a992181

2 / The unsuccessful fix

Exit 1

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

N = 1
observations = []
def solve(row, pending, response, draft):
    key=(response['row'],response['column'])
    request=pending.get(key)
    if request is None or request['id']!=response['request']: return {'row':row,'pending':sorted(pending.items()),'draft':sorted(draft.items()),'error':None}
    if row['id']!=response['row']: return {'row':row,'pending':sorted(pending.items()),'draft':sorted(draft.items()),'error':None}
    next_pending=dict(pending); next_pending.pop(key)
    if response.get('error') is not None: return {'row':row,'pending':sorted(next_pending.items()),'draft':sorted(draft.items()),'error':response['error']}
    out=dict(row)
    if response['revision']<=row['revision']: return {'row':out,'pending':sorted(next_pending.items()),'draft':sorted(draft.items()),'error':'stale'}
    out[response['column']]=response['value']; out['revision']=response['revision']
    next_draft=dict(draft)
    if key in next_draft and next_draft[key]['edit_id']==request['edit_id']: next_draft.pop(key)
    return {'row':out,'pending':sorted(next_pending.items()),'draft':sorted(next_draft.items()),'error':None}
def check(label, actual, expected):
    observations.append({"check": label, "actual": actual, "expected": expected, "passed": actual == expected})
if N == 1:
    check('canonical server response', solve({'id':'r','a':'old','revision':3}, {('r','a'):{'id':2,'edit_id':9,'value':' raw '},('r','b'):{'id':3,'edit_id':10,'value':'B'}}, {'row':'r','column':'a','request':2,'revision':8,'value':'raw'+str(1),'warning':'informational'}, {('r','a'):{'edit_id':9,'value':' raw '},('r','b'):{'edit_id':10,'value':'B'}}), {'row': {'id': 'r', 'a': 'raw1', 'revision': 8}, 'pending': [(('r', 'b'), {'id': 3, 'edit_id': 10, 'value': 'B'})], 'draft': [(('r', 'b'), {'edit_id': 10, 'value': 'B'})], 'error': None})
    check('late old request', solve({'id':'r','a':'old','revision':3}, {('r','a'):{'id':2,'edit_id':9,'value':'v'}}, {'row':'r','column':'a','request':1,'revision':4,'value':'old ack'}, {}), {'row': {'id': 'r', 'a': 'old', 'revision': 3}, 'pending': [(('r', 'a'), {'id': 2, 'edit_id': 9, 'value': 'v'})], 'draft': [], 'error': None})
    check('different row', solve({'id':'other','a':'old','revision':3}, {('r','a'):{'id':2,'edit_id':9,'value':'v'}}, {'row':'r','column':'a','request':2,'revision':4,'value':'ack'}, {}), {'row': {'id': 'other', 'a': 'old', 'revision': 3}, 'pending': [(('r', 'a'), {'id': 2, 'edit_id': 9, 'value': 'v'})], 'draft': [], 'error': None})
    check('empty error message', solve({'id':'r','a':'old','revision':3}, {('r','a'):{'id':2,'edit_id':9,'value':'v'}}, {'row':'r','column':'a','request':2,'revision':4,'value':'ack','error':''}, {('r','a'):{'edit_id':9,'value':'v'}}), {'row': {'id': 'r', 'a': 'old', 'revision': 3}, 'pending': [], 'draft': [(('r', 'a'), {'edit_id': 9, 'value': 'v'})], 'error': ''})
    check('stale revision', solve({'id':'r','a':'new','revision':7}, {('r','a'):{'id':2,'edit_id':9,'value':'v'}}, {'row':'r','column':'a','request':2,'revision':6,'value':'ack'}, {}), {'row': {'id': 'r', 'a': 'new', 'revision': 7}, 'pending': [], 'draft': [], 'error': 'stale'})
    check('equal revision allowed', solve({'id':'r','a':'old','revision':3}, {('r','a'):{'id':2,'edit_id':9,'value':'v'}}, {'row':'r','column':'a','request':2,'revision':3,'value':'ack'}, {}), {'row': {'id': 'r', 'a': 'ack', 'revision': 3}, 'pending': [], 'draft': [], 'error': None})
    check('new edit same value', solve({'id':'r','a':'old','revision':3}, {('r','a'):{'id':2,'edit_id':9,'value':'v'}}, {'row':'r','column':'a','request':2,'revision':4,'value':'ack'}, {('r','a'):{'edit_id':10,'value':'v'}}), {'row': {'id': 'r', 'a': 'ack', 'revision': 4}, 'pending': [], 'draft': [(('r', 'a'), {'edit_id': 10, 'value': 'v'})], 'error': None})

if N == 2:
    check('canonical server response', solve({'id':'r','a':'old','revision':3}, {('r','a'):{'id':2,'edit_id':9,'value':' raw '},('r','b'):{'id':3,'edit_id':10,'value':'B'}}, {'row':'r','column':'a','request':2,'revision':8,'value':'raw'+str(2),'warning':'informational'}, {('r','a'):{'edit_id':9,'value':' raw '},('r','b'):{'edit_id':10,'value':'B'}}), {'row': {'id': 'r', 'a': 'raw2', 'revision': 8}, 'pending': [(('r', 'b'), {'id': 3, 'edit_id': 10, 'value': 'B'})], 'draft': [(('r', 'b'), {'edit_id': 10, 'value': 'B'})], 'error': None})
    check('late old request', solve({'id':'r','a':'old','revision':3}, {('r','a'):{'id':2,'edit_id':9,'value':'v'}}, {'row':'r','column':'a','request':1,'revision':4,'value':'old ack'}, {}), {'row': {'id': 'r', 'a': 'old', 'revision': 3}, 'pending': [(('r', 'a'), {'id': 2, 'edit_id': 9, 'value': 'v'})], 'draft': [], 'error': None})
    check('different row', solve({'id':'other','a':'old','revision':3}, {('r','a'):{'id':2,'edit_id':9,'value':'v'}}, {'row':'r','column':'a','request':2,'revision':4,'value':'ack'}, {}), {'row': {'id': 'other', 'a': 'old', 'revision': 3}, 'pending': [(('r', 'a'), {'id': 2, 'edit_id': 9, 'value': 'v'})], 'draft': [], 'error': None})
    check('empty error message', solve({'id':'r','a':'old','revision':3}, {('r','a'):{'id':2,'edit_id':9,'value':'v'}}, {'row':'r','column':'a','request':2,'revision':4,'value':'ack','error':''}, {('r','a'):{'edit_id':9,'value':'v'}}), {'row': {'id': 'r', 'a': 'old', 'revision': 3}, 'pending': [], 'draft': [(('r', 'a'), {'edit_id': 9, 'value': 'v'})], 'error': ''})
    check('stale revision', solve({'id':'r','a':'new','revision':7}, {('r','a'):{'id':2,'edit_id':9,'value':'v'}}, {'row':'r','column':'a','request':2,'revision':6,'value':'ack'}, {}), {'row': {'id': 'r', 'a': 'new', 'revision': 7}, 'pending': [], 'draft': [], 'error': 'stale'})
    check('equal revision allowed', solve({'id':'r','a':'old','revision':3}, {('r','a'):{'id':2,'edit_id':9,'value':'v'}}, {'row':'r','column':'a','request':2,'revision':3,'value':'ack'}, {}), {'row': {'id': 'r', 'a': 'ack', 'revision': 3}, 'pending': [], 'draft': [], 'error': None})
    check('new edit same value', solve({'id':'r','a':'old','revision':3}, {('r','a'):{'id':2,'edit_id':9,'value':'v'}}, {'row':'r','column':'a','request':2,'revision':4,'value':'ack'}, {('r','a'):{'edit_id':10,'value':'v'}}), {'row': {'id': 'r', 'a': 'ack', 'revision': 4}, 'pending': [], 'draft': [(('r', 'a'), {'edit_id': 10, 'value': 'v'})], 'error': None})

if N == 3:
    check('canonical server response', solve({'id':'r','a':'old','revision':3}, {('r','a'):{'id':2,'edit_id':9,'value':' raw '},('r','b'):{'id':3,'edit_id':10,'value':'B'}}, {'row':'r','column':'a','request':2,'revision':8,'value':'raw'+str(3),'warning':'informational'}, {('r','a'):{'edit_id':9,'value':' raw '},('r','b'):{'edit_id':10,'value':'B'}}), {'row': {'id': 'r', 'a': 'raw3', 'revision': 8}, 'pending': [(('r', 'b'), {'id': 3, 'edit_id': 10, 'value': 'B'})], 'draft': [(('r', 'b'), {'edit_id': 10, 'value': 'B'})], 'error': None})
    check('late old request', solve({'id':'r','a':'old','revision':3}, {('r','a'):{'id':2,'edit_id':9,'value':'v'}}, {'row':'r','column':'a','request':1,'revision':4,'value':'old ack'}, {}), {'row': {'id': 'r', 'a': 'old', 'revision': 3}, 'pending': [(('r', 'a'), {'id': 2, 'edit_id': 9, 'value': 'v'})], 'draft': [], 'error': None})
    check('different row', solve({'id':'other','a':'old','revision':3}, {('r','a'):{'id':2,'edit_id':9,'value':'v'}}, {'row':'r','column':'a','request':2,'revision':4,'value':'ack'}, {}), {'row': {'id': 'other', 'a': 'old', 'revision': 3}, 'pending': [(('r', 'a'), {'id': 2, 'edit_id': 9, 'value': 'v'})], 'draft': [], 'error': None})
    check('empty error message', solve({'id':'r','a':'old','revision':3}, {('r','a'):{'id':2,'edit_id':9,'value':'v'}}, {'row':'r','column':'a','request':2,'revision':4,'value':'ack','error':''}, {('r','a'):{'edit_id':9,'value':'v'}}), {'row': {'id': 'r', 'a': 'old', 'revision': 3}, 'pending': [], 'draft': [(('r', 'a'), {'edit_id': 9, 'value': 'v'})], 'error': ''})
    check('stale revision', solve({'id':'r','a':'new','revision':7}, {('r','a'):{'id':2,'edit_id':9,'value':'v'}}, {'row':'r','column':'a','request':2,'revision':6,'value':'ack'}, {}), {'row': {'id': 'r', 'a': 'new', 'revision': 7}, 'pending': [], 'draft': [], 'error': 'stale'})
    check('equal revision allowed', solve({'id':'r','a':'old','revision':3}, {('r','a'):{'id':2,'edit_id':9,'value':'v'}}, {'row':'r','column':'a','request':2,'revision':3,'value':'ack'}, {}), {'row': {'id': 'r', 'a': 'ack', 'revision': 3}, 'pending': [], 'draft': [], 'error': None})
    check('new edit same value', solve({'id':'r','a':'old','revision':3}, {('r','a'):{'id':2,'edit_id':9,'value':'v'}}, {'row':'r','column':'a','request':2,'revision':4,'value':'ack'}, {('r','a'):{'edit_id':10,'value':'v'}}), {'row': {'id': 'r', 'a': 'ack', 'revision': 4}, 'pending': [], 'draft': [(('r', 'a'), {'edit_id': 10, 'value': 'v'})], 'error': None})

if N == 4:
    check('canonical server response', solve({'id':'r','a':'old','revision':3}, {('r','a'):{'id':2,'edit_id':9,'value':' raw '},('r','b'):{'id':3,'edit_id':10,'value':'B'}}, {'row':'r','column':'a','request':2,'revision':8,'value':'raw'+str(4),'warning':'informational'}, {('r','a'):{'edit_id':9,'value':' raw '},('r','b'):{'edit_id':10,'value':'B'}}), {'row': {'id': 'r', 'a': 'raw4', 'revision': 8}, 'pending': [(('r', 'b'), {'id': 3, 'edit_id': 10, 'value': 'B'})], 'draft': [(('r', 'b'), {'edit_id': 10, 'value': 'B'})], 'error': None})
    check('late old request', solve({'id':'r','a':'old','revision':3}, {('r','a'):{'id':2,'edit_id':9,'value':'v'}}, {'row':'r','column':'a','request':1,'revision':4,'value':'old ack'}, {}), {'row': {'id': 'r', 'a': 'old', 'revision': 3}, 'pending': [(('r', 'a'), {'id': 2, 'edit_id': 9, 'value': 'v'})], 'draft': [], 'error': None})
    check('different row', solve({'id':'other','a':'old','revision':3}, {('r','a'):{'id':2,'edit_id':9,'value':'v'}}, {'row':'r','column':'a','request':2,'revision':4,'value':'ack'}, {}), {'row': {'id': 'other', 'a': 'old', 'revision': 3}, 'pending': [(('r', 'a'), {'id': 2, 'edit_id': 9, 'value': 'v'})], 'draft': [], 'error': None})
    check('empty error message', solve({'id':'r','a':'old','revision':3}, {('r','a'):{'id':2,'edit_id':9,'value':'v'}}, {'row':'r','column':'a','request':2,'revision':4,'value':'ack','error':''}, {('r','a'):{'edit_id':9,'value':'v'}}), {'row': {'id': 'r', 'a': 'old', 'revision': 3}, 'pending': [], 'draft': [(('r', 'a'), {'edit_id': 9, 'value': 'v'})], 'error': ''})
    check('stale revision', solve({'id':'r','a':'new','revision':7}, {('r','a'):{'id':2,'edit_id':9,'value':'v'}}, {'row':'r','column':'a','request':2,'revision':6,'value':'ack'}, {}), {'row': {'id': 'r', 'a': 'new', 'revision': 7}, 'pending': [], 'draft': [], 'error': 'stale'})
    check('equal revision allowed', solve({'id':'r','a':'old','revision':3}, {('r','a'):{'id':2,'edit_id':9,'value':'v'}}, {'row':'r','column':'a','request':2,'revision':3,'value':'ack'}, {}), {'row': {'id': 'r', 'a': 'ack', 'revision': 3}, 'pending': [], 'draft': [], 'error': None})
    check('new edit same value', solve({'id':'r','a':'old','revision':3}, {('r','a'):{'id':2,'edit_id':9,'value':'v'}}, {'row':'r','column':'a','request':2,'revision':4,'value':'ack'}, {('r','a'):{'edit_id':10,'value':'v'}}), {'row': {'id': 'r', 'a': 'ack', 'revision': 4}, 'pending': [], 'draft': [(('r', 'a'), {'edit_id': 10, 'value': 'v'})], 'error': None})

if N == 5:
    check('canonical server response', solve({'id':'r','a':'old','revision':3}, {('r','a'):{'id':2,'edit_id':9,'value':' raw '},('r','b'):{'id':3,'edit_id':10,'value':'B'}}, {'row':'r','column':'a','request':2,'revision':8,'value':'raw'+str(5),'warning':'informational'}, {('r','a'):{'edit_id':9,'value':' raw '},('r','b'):{'edit_id':10,'value':'B'}}), {'row': {'id': 'r', 'a': 'raw5', 'revision': 8}, 'pending': [(('r', 'b'), {'id': 3, 'edit_id': 10, 'value': 'B'})], 'draft': [(('r', 'b'), {'edit_id': 10, 'value': 'B'})], 'error': None})
    check('late old request', solve({'id':'r','a':'old','revision':3}, {('r','a'):{'id':2,'edit_id':9,'value':'v'}}, {'row':'r','column':'a','request':1,'revision':4,'value':'old ack'}, {}), {'row': {'id': 'r', 'a': 'old', 'revision': 3}, 'pending': [(('r', 'a'), {'id': 2, 'edit_id': 9, 'value': 'v'})], 'draft': [], 'error': None})
    check('different row', solve({'id':'other','a':'old','revision':3}, {('r','a'):{'id':2,'edit_id':9,'value':'v'}}, {'row':'r','column':'a','request':2,'revision':4,'value':'ack'}, {}), {'row': {'id': 'other', 'a': 'old', 'revision': 3}, 'pending': [(('r', 'a'), {'id': 2, 'edit_id': 9, 'value': 'v'})], 'draft': [], 'error': None})
    check('empty error message', solve({'id':'r','a':'old','revision':3}, {('r','a'):{'id':2,'edit_id':9,'value':'v'}}, {'row':'r','column':'a','request':2,'revision':4,'value':'ack','error':''}, {('r','a'):{'edit_id':9,'value':'v'}}), {'row': {'id': 'r', 'a': 'old', 'revision': 3}, 'pending': [], 'draft': [(('r', 'a'), {'edit_id': 9, 'value': 'v'})], 'error': ''})
    check('stale revision', solve({'id':'r','a':'new','revision':7}, {('r','a'):{'id':2,'edit_id':9,'value':'v'}}, {'row':'r','column':'a','request':2,'revision':6,'value':'ack'}, {}), {'row': {'id': 'r', 'a': 'new', 'revision': 7}, 'pending': [], 'draft': [], 'error': 'stale'})
    check('equal revision allowed', solve({'id':'r','a':'old','revision':3}, {('r','a'):{'id':2,'edit_id':9,'value':'v'}}, {'row':'r','column':'a','request':2,'revision':3,'value':'ack'}, {}), {'row': {'id': 'r', 'a': 'ack', 'revision': 3}, 'pending': [], 'draft': [], 'error': None})
    check('new edit same value', solve({'id':'r','a':'old','revision':3}, {('r','a'):{'id':2,'edit_id':9,'value':'v'}}, {'row':'r','column':'a','request':2,'revision':4,'value':'ack'}, {('r','a'):{'edit_id':10,'value':'v'}}), {'row': {'id': 'r', 'a': 'ack', 'revision': 4}, 'pending': [], 'draft': [(('r', 'a'), {'edit_id': 10, 'value': 'v'})], 'error': 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 fixture	Actual	Expected	Outcome
canonical server response	`{'draft': [[['r', 'b'], {'edit_id': 10, 'value': 'B'}]], 'error': None, 'pending': [[['r', 'b'], {'edit_id': 10, 'id': 3, 'value': 'B'}]], 'row': {'a': 'raw1', 'id': 'r', 'revision': 8}}`	`{'draft': [[['r', 'b'], {'edit_id': 10, 'value': 'B'}]], 'error': None, 'pending': [[['r', 'b'], {'edit_id': 10, 'id': 3, 'value': 'B'}]], 'row': {'a': 'raw1', 'id': 'r', 'revision': 8}}`	Passed
late old request	`{'draft': [], 'error': None, 'pending': [[['r', 'a'], {'edit_id': 9, 'id': 2, 'value': 'v'}]], 'row': {'a': 'old', 'id': 'r', 'revision': 3}}`	`{'draft': [], 'error': None, 'pending': [[['r', 'a'], {'edit_id': 9, 'id': 2, 'value': 'v'}]], 'row': {'a': 'old', 'id': 'r', 'revision': 3}}`	Passed
different row	`{'draft': [], 'error': None, 'pending': [[['r', 'a'], {'edit_id': 9, 'id': 2, 'value': 'v'}]], 'row': {'a': 'old', 'id': 'other', 'revision': 3}}`	`{'draft': [], 'error': None, 'pending': [[['r', 'a'], {'edit_id': 9, 'id': 2, 'value': 'v'}]], 'row': {'a': 'old', 'id': 'other', 'revision': 3}}`	Passed
empty error message	`{'draft': [[['r', 'a'], {'edit_id': 9, 'value': 'v'}]], 'error': '', 'pending': [], 'row': {'a': 'old', 'id': 'r', 'revision': 3}}`	`{'draft': [[['r', 'a'], {'edit_id': 9, 'value': 'v'}]], 'error': '', 'pending': [], 'row': {'a': 'old', 'id': 'r', 'revision': 3}}`	Passed
stale revision	`{'draft': [], 'error': 'stale', 'pending': [], 'row': {'a': 'new', 'id': 'r', 'revision': 7}}`	`{'draft': [], 'error': 'stale', 'pending': [], 'row': {'a': 'new', 'id': 'r', 'revision': 7}}`	Passed
equal revision allowed	`{'draft': [], 'error': 'stale', 'pending': [], 'row': {'a': 'old', 'id': 'r', 'revision': 3}}`	`{'draft': [], 'error': None, 'pending': [], 'row': {'a': 'ack', 'id': 'r', 'revision': 3}}`	Failed
new edit same value	`{'draft': [[['r', 'a'], {'edit_id': 10, 'value': 'v'}]], 'error': None, 'pending': [], 'row': {'a': 'ack', 'id': 'r', 'revision': 4}}`	`{'draft': [[['r', 'a'], {'edit_id': 10, 'value': 'v'}]], 'error': None, 'pending': [], 'row': {'a': 'ack', 'id': 'r', 'revision': 4}}`	Passed

SHA-256 / ea79deaf6af0a7397f11c3b9c11aa5a9500a2d31ee06a72e636924a677ac9258

HELD IN THE MEMBER ARCHIVE

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

This mechanism has 7 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

Pending entries and matching drafts are well-formed; revisions are integers. Pair-keyed maps serialize as sorted pairs. 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 2026-09-29T14:43:08.694742+00:00.

Case digest / 28435fcf1c34d481c48bdfbd35bbb1ad7e7eab58f94b9e67193a53391389eec9