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FA-36016 / Tab interfaces / Open access

Pin group interaction: remaining group count · case 01

The tab workspace reports an incorrect remaining group count.

Verified by executionVariant 1 · 6 checks per implementationDownload source bundle ↓JSON ↗

ROOT CAUSE

The remaining group count decision uses len(x['members']) instead of sum(t!=x['pin'] for t in x['members']).

THE FAILURE

The remaining group count decision uses len(x['members']) instead of sum(t!=x['pin'] for t in x['members']).

Unsuccessful approach: The partial repair max(0,len(x['members'])-2) still violates a workspace boundary or normal case.

Case contract

Pinning a tab removes it from its group, moves it behind existing pins, shrinks group count and dissolves empty group headers while keeping selection.

Why this case matters

Offline tab/panel workspace behavior; no browser or desktop framework is emulated.

1 / The failure

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

N = 1
observations = []
def solve(x):
    r0 = [t for t in x['members'] if t!=x['pin']]
    r1 = x['pins']+[x['pin']] if x['pin'] not in x['pins'] else x['pins']
    r2 = len(x['pins'])
    r3 = len(x['members'])
    r4 = not any(t!=x['pin'] for t in x['members'])
    r5 = x['active']
    return [r0,r1,r2,r3,r4,r5]
def check(label, actual, expected):
    observations.append({"check": label, "actual": actual, "expected": expected, "passed": actual == expected})
fixtures = {1: [({'tabs': ['p', 'a', 'b', 'c'], 'pins': ['p'], 'members': ['a', 'b'], 'pin': 'b', 'active': 'a'}, [['a'], ['p', 'b'], 1, 1, False, 'a']), ({'tabs': ['p', 'a', 'b', 'c'], 'pins': ['p'], 'members': ['a', 'b'], 'pin': 'a', 'active': 'a'}, [['b'], ['p', 'a'], 1, 1, False, 'a']), ({'tabs': ['p', 'a', 'b', 'c'], 'pins': ['p'], 'members': ['b'], 'pin': 'b', 'active': 'a'}, [[], ['p', 'b'], 1, 0, True, 'a']), ({'tabs': ['p', 'a', 'b', 'c'], 'pins': [], 'members': ['a', 'b'], 'pin': 'b', 'active': 'a'}, [['a'], ['b'], 0, 1, False, 'a']), ({'tabs': ['p', 'a', 'b', 'c'], 'pins': ['p'], 'members': ['a', 'b'], 'pin': 'b', 'active': 'b'}, [['a'], ['p', 'b'], 1, 1, False, 'b']), ({'tabs': ['p', 'a', 'b', 'c'], 'pins': ['p'], 'members': ['a', 'b', 'c'], 'pin': 'b', 'active': 'a'}, [['a', 'c'], ['p', 'b'], 1, 2, False, 'a'])], 2: [({'tabs': ['p', 'a', 'b', 'c', 'background0'], 'pins': ['p'], 'members': ['a', 'b'], 'pin': 'b', 'active': 'a'}, [['a'], ['p', 'b'], 1, 1, False, 'a']), ({'tabs': ['p', 'a', 'b', 'c', 'background0'], 'pins': ['p'], 'members': ['a', 'b'], 'pin': 'a', 'active': 'a'}, [['b'], ['p', 'a'], 1, 1, False, 'a']), ({'tabs': ['p', 'a', 'b', 'c', 'background0'], 'pins': ['p'], 'members': ['b'], 'pin': 'b', 'active': 'a'}, [[], ['p', 'b'], 1, 0, True, 'a']), ({'tabs': ['p', 'a', 'b', 'c', 'background0'], 'pins': [], 'members': ['a', 'b'], 'pin': 'b', 'active': 'a'}, [['a'], ['b'], 0, 1, False, 'a']), ({'tabs': ['p', 'a', 'b', 'c', 'background0'], 'pins': ['p'], 'members': ['a', 'b'], 'pin': 'b', 'active': 'b'}, [['a'], ['p', 'b'], 1, 1, False, 'b']), ({'tabs': ['p', 'a', 'b', 'c', 'background0'], 'pins': ['p'], 'members': ['a', 'b', 'c'], 'pin': 'b', 'active': 'a'}, [['a', 'c'], ['p', 'b'], 1, 2, False, 'a'])], 3: [({'tabs': ['p', 'a', 'b', 'c', 'background0', 'background1'], 'pins': ['p'], 'members': ['a', 'b'], 'pin': 'b', 'active': 'a'}, [['a'], ['p', 'b'], 1, 1, False, 'a']), ({'tabs': ['p', 'a', 'b', 'c', 'background0', 'background1'], 'pins': ['p'], 'members': ['a', 'b'], 'pin': 'a', 'active': 'a'}, [['b'], ['p', 'a'], 1, 1, False, 'a']), ({'tabs': ['p', 'a', 'b', 'c', 'background0', 'background1'], 'pins': ['p'], 'members': ['b'], 'pin': 'b', 'active': 'a'}, [[], ['p', 'b'], 1, 0, True, 'a']), ({'tabs': ['p', 'a', 'b', 'c', 'background0', 'background1'], 'pins': [], 'members': ['a', 'b'], 'pin': 'b', 'active': 'a'}, [['a'], ['b'], 0, 1, False, 'a']), ({'tabs': ['p', 'a', 'b', 'c', 'background0', 'background1'], 'pins': ['p'], 'members': ['a', 'b'], 'pin': 'b', 'active': 'b'}, [['a'], ['p', 'b'], 1, 1, False, 'b']), ({'tabs': ['p', 'a', 'b', 'c', 'background0', 'background1'], 'pins': ['p'], 'members': ['a', 'b', 'c'], 'pin': 'b', 'active': 'a'}, [['a', 'c'], ['p', 'b'], 1, 2, False, 'a'])], 4: [({'tabs': ['p', 'a', 'b', 'c', 'background0', 'background1', 'background2'], 'pins': ['p'], 'members': ['a', 'b'], 'pin': 'b', 'active': 'a'}, [['a'], ['p', 'b'], 1, 1, False, 'a']), ({'tabs': ['p', 'a', 'b', 'c', 'background0', 'background1', 'background2'], 'pins': ['p'], 'members': ['a', 'b'], 'pin': 'a', 'active': 'a'}, [['b'], ['p', 'a'], 1, 1, False, 'a']), ({'tabs': ['p', 'a', 'b', 'c', 'background0', 'background1', 'background2'], 'pins': ['p'], 'members': ['b'], 'pin': 'b', 'active': 'a'}, [[], ['p', 'b'], 1, 0, True, 'a']), ({'tabs': ['p', 'a', 'b', 'c', 'background0', 'background1', 'background2'], 'pins': [], 'members': ['a', 'b'], 'pin': 'b', 'active': 'a'}, [['a'], ['b'], 0, 1, False, 'a']), ({'tabs': ['p', 'a', 'b', 'c', 'background0', 'background1', 'background2'], 'pins': ['p'], 'members': ['a', 'b'], 'pin': 'b', 'active': 'b'}, [['a'], ['p', 'b'], 1, 1, False, 'b']), ({'tabs': ['p', 'a', 'b', 'c', 'background0', 'background1', 'background2'], 'pins': ['p'], 'members': ['a', 'b', 'c'], 'pin': 'b', 'active': 'a'}, [['a', 'c'], ['p', 'b'], 1, 2, False, 'a'])], 5: [({'tabs': ['p', 'a', 'b', 'c', 'background0', 'background1', 'background2', 'background3'], 'pins': ['p'], 'members': ['a', 'b'], 'pin': 'b', 'active': 'a'}, [['a'], ['p', 'b'], 1, 1, False, 'a']), ({'tabs': ['p', 'a', 'b', 'c', 'background0', 'background1', 'background2', 'background3'], 'pins': ['p'], 'members': ['a', 'b'], 'pin': 'a', 'active': 'a'}, [['b'], ['p', 'a'], 1, 1, False, 'a']), ({'tabs': ['p', 'a', 'b', 'c', 'background0', 'background1', 'background2', 'background3'], 'pins': ['p'], 'members': ['b'], 'pin': 'b', 'active': 'a'}, [[], ['p', 'b'], 1, 0, True, 'a']), ({'tabs': ['p', 'a', 'b', 'c', 'background0', 'background1', 'background2', 'background3'], 'pins': [], 'members': ['a', 'b'], 'pin': 'b', 'active': 'a'}, [['a'], ['b'], 0, 1, False, 'a']), ({'tabs': ['p', 'a', 'b', 'c', 'background0', 'background1', 'background2', 'background3'], 'pins': ['p'], 'members': ['a', 'b'], 'pin': 'b', 'active': 'b'}, [['a'], ['p', 'b'], 1, 1, False, 'b']), ({'tabs': ['p', 'a', 'b', 'c', 'background0', 'background1', 'background2', 'background3'], 'pins': ['p'], 'members': ['a', 'b', 'c'], 'pin': 'b', 'active': 'a'}, [['a', 'c'], ['p', 'b'], 1, 2, False, 'a'])]}
for i, (inputs, expected) in enumerate(fixtures[N]):
    check("workspace regression "+str(i), solve(inputs), 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
workspace regression 0[['a'], ['p', 'b'], 1, 2, False, 'a'][['a'], ['p', 'b'], 1, 1, False, 'a']Failed
workspace regression 1[['b'], ['p', 'a'], 1, 2, False, 'a'][['b'], ['p', 'a'], 1, 1, False, 'a']Failed
workspace regression 2[[], ['p', 'b'], 1, 1, True, 'a'][[], ['p', 'b'], 1, 0, True, 'a']Failed
workspace regression 3[['a'], ['b'], 0, 2, False, 'a'][['a'], ['b'], 0, 1, False, 'a']Failed
workspace regression 4[['a'], ['p', 'b'], 1, 2, False, 'b'][['a'], ['p', 'b'], 1, 1, False, 'b']Failed
workspace regression 5[['a', 'c'], ['p', 'b'], 1, 3, False, 'a'][['a', 'c'], ['p', 'b'], 1, 2, False, 'a']Failed

SHA-256 / 7097a130d1c4e548947527db117afcf07b4cf7953d69fb4728cd1515412c7210

2 / The unsuccessful fix

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

N = 1
observations = []
def solve(x):
    r0 = [t for t in x['members'] if t!=x['pin']]
    r1 = x['pins']+[x['pin']] if x['pin'] not in x['pins'] else x['pins']
    r2 = len(x['pins'])
    r3 = max(0,len(x['members'])-2)
    r4 = not any(t!=x['pin'] for t in x['members'])
    r5 = x['active']
    return [r0,r1,r2,r3,r4,r5]
def check(label, actual, expected):
    observations.append({"check": label, "actual": actual, "expected": expected, "passed": actual == expected})
fixtures = {1: [({'tabs': ['p', 'a', 'b', 'c'], 'pins': ['p'], 'members': ['a', 'b'], 'pin': 'b', 'active': 'a'}, [['a'], ['p', 'b'], 1, 1, False, 'a']), ({'tabs': ['p', 'a', 'b', 'c'], 'pins': ['p'], 'members': ['a', 'b'], 'pin': 'a', 'active': 'a'}, [['b'], ['p', 'a'], 1, 1, False, 'a']), ({'tabs': ['p', 'a', 'b', 'c'], 'pins': ['p'], 'members': ['b'], 'pin': 'b', 'active': 'a'}, [[], ['p', 'b'], 1, 0, True, 'a']), ({'tabs': ['p', 'a', 'b', 'c'], 'pins': [], 'members': ['a', 'b'], 'pin': 'b', 'active': 'a'}, [['a'], ['b'], 0, 1, False, 'a']), ({'tabs': ['p', 'a', 'b', 'c'], 'pins': ['p'], 'members': ['a', 'b'], 'pin': 'b', 'active': 'b'}, [['a'], ['p', 'b'], 1, 1, False, 'b']), ({'tabs': ['p', 'a', 'b', 'c'], 'pins': ['p'], 'members': ['a', 'b', 'c'], 'pin': 'b', 'active': 'a'}, [['a', 'c'], ['p', 'b'], 1, 2, False, 'a'])], 2: [({'tabs': ['p', 'a', 'b', 'c', 'background0'], 'pins': ['p'], 'members': ['a', 'b'], 'pin': 'b', 'active': 'a'}, [['a'], ['p', 'b'], 1, 1, False, 'a']), ({'tabs': ['p', 'a', 'b', 'c', 'background0'], 'pins': ['p'], 'members': ['a', 'b'], 'pin': 'a', 'active': 'a'}, [['b'], ['p', 'a'], 1, 1, False, 'a']), ({'tabs': ['p', 'a', 'b', 'c', 'background0'], 'pins': ['p'], 'members': ['b'], 'pin': 'b', 'active': 'a'}, [[], ['p', 'b'], 1, 0, True, 'a']), ({'tabs': ['p', 'a', 'b', 'c', 'background0'], 'pins': [], 'members': ['a', 'b'], 'pin': 'b', 'active': 'a'}, [['a'], ['b'], 0, 1, False, 'a']), ({'tabs': ['p', 'a', 'b', 'c', 'background0'], 'pins': ['p'], 'members': ['a', 'b'], 'pin': 'b', 'active': 'b'}, [['a'], ['p', 'b'], 1, 1, False, 'b']), ({'tabs': ['p', 'a', 'b', 'c', 'background0'], 'pins': ['p'], 'members': ['a', 'b', 'c'], 'pin': 'b', 'active': 'a'}, [['a', 'c'], ['p', 'b'], 1, 2, False, 'a'])], 3: [({'tabs': ['p', 'a', 'b', 'c', 'background0', 'background1'], 'pins': ['p'], 'members': ['a', 'b'], 'pin': 'b', 'active': 'a'}, [['a'], ['p', 'b'], 1, 1, False, 'a']), ({'tabs': ['p', 'a', 'b', 'c', 'background0', 'background1'], 'pins': ['p'], 'members': ['a', 'b'], 'pin': 'a', 'active': 'a'}, [['b'], ['p', 'a'], 1, 1, False, 'a']), ({'tabs': ['p', 'a', 'b', 'c', 'background0', 'background1'], 'pins': ['p'], 'members': ['b'], 'pin': 'b', 'active': 'a'}, [[], ['p', 'b'], 1, 0, True, 'a']), ({'tabs': ['p', 'a', 'b', 'c', 'background0', 'background1'], 'pins': [], 'members': ['a', 'b'], 'pin': 'b', 'active': 'a'}, [['a'], ['b'], 0, 1, False, 'a']), ({'tabs': ['p', 'a', 'b', 'c', 'background0', 'background1'], 'pins': ['p'], 'members': ['a', 'b'], 'pin': 'b', 'active': 'b'}, [['a'], ['p', 'b'], 1, 1, False, 'b']), ({'tabs': ['p', 'a', 'b', 'c', 'background0', 'background1'], 'pins': ['p'], 'members': ['a', 'b', 'c'], 'pin': 'b', 'active': 'a'}, [['a', 'c'], ['p', 'b'], 1, 2, False, 'a'])], 4: [({'tabs': ['p', 'a', 'b', 'c', 'background0', 'background1', 'background2'], 'pins': ['p'], 'members': ['a', 'b'], 'pin': 'b', 'active': 'a'}, [['a'], ['p', 'b'], 1, 1, False, 'a']), ({'tabs': ['p', 'a', 'b', 'c', 'background0', 'background1', 'background2'], 'pins': ['p'], 'members': ['a', 'b'], 'pin': 'a', 'active': 'a'}, [['b'], ['p', 'a'], 1, 1, False, 'a']), ({'tabs': ['p', 'a', 'b', 'c', 'background0', 'background1', 'background2'], 'pins': ['p'], 'members': ['b'], 'pin': 'b', 'active': 'a'}, [[], ['p', 'b'], 1, 0, True, 'a']), ({'tabs': ['p', 'a', 'b', 'c', 'background0', 'background1', 'background2'], 'pins': [], 'members': ['a', 'b'], 'pin': 'b', 'active': 'a'}, [['a'], ['b'], 0, 1, False, 'a']), ({'tabs': ['p', 'a', 'b', 'c', 'background0', 'background1', 'background2'], 'pins': ['p'], 'members': ['a', 'b'], 'pin': 'b', 'active': 'b'}, [['a'], ['p', 'b'], 1, 1, False, 'b']), ({'tabs': ['p', 'a', 'b', 'c', 'background0', 'background1', 'background2'], 'pins': ['p'], 'members': ['a', 'b', 'c'], 'pin': 'b', 'active': 'a'}, [['a', 'c'], ['p', 'b'], 1, 2, False, 'a'])], 5: [({'tabs': ['p', 'a', 'b', 'c', 'background0', 'background1', 'background2', 'background3'], 'pins': ['p'], 'members': ['a', 'b'], 'pin': 'b', 'active': 'a'}, [['a'], ['p', 'b'], 1, 1, False, 'a']), ({'tabs': ['p', 'a', 'b', 'c', 'background0', 'background1', 'background2', 'background3'], 'pins': ['p'], 'members': ['a', 'b'], 'pin': 'a', 'active': 'a'}, [['b'], ['p', 'a'], 1, 1, False, 'a']), ({'tabs': ['p', 'a', 'b', 'c', 'background0', 'background1', 'background2', 'background3'], 'pins': ['p'], 'members': ['b'], 'pin': 'b', 'active': 'a'}, [[], ['p', 'b'], 1, 0, True, 'a']), ({'tabs': ['p', 'a', 'b', 'c', 'background0', 'background1', 'background2', 'background3'], 'pins': [], 'members': ['a', 'b'], 'pin': 'b', 'active': 'a'}, [['a'], ['b'], 0, 1, False, 'a']), ({'tabs': ['p', 'a', 'b', 'c', 'background0', 'background1', 'background2', 'background3'], 'pins': ['p'], 'members': ['a', 'b'], 'pin': 'b', 'active': 'b'}, [['a'], ['p', 'b'], 1, 1, False, 'b']), ({'tabs': ['p', 'a', 'b', 'c', 'background0', 'background1', 'background2', 'background3'], 'pins': ['p'], 'members': ['a', 'b', 'c'], 'pin': 'b', 'active': 'a'}, [['a', 'c'], ['p', 'b'], 1, 2, False, 'a'])]}
for i, (inputs, expected) in enumerate(fixtures[N]):
    check("workspace regression "+str(i), solve(inputs), 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
workspace regression 0[['a'], ['p', 'b'], 1, 0, False, 'a'][['a'], ['p', 'b'], 1, 1, False, 'a']Failed
workspace regression 1[['b'], ['p', 'a'], 1, 0, False, 'a'][['b'], ['p', 'a'], 1, 1, False, 'a']Failed
workspace regression 2[[], ['p', 'b'], 1, 0, True, 'a'][[], ['p', 'b'], 1, 0, True, 'a']Passed
workspace regression 3[['a'], ['b'], 0, 0, False, 'a'][['a'], ['b'], 0, 1, False, 'a']Failed
workspace regression 4[['a'], ['p', 'b'], 1, 0, False, 'b'][['a'], ['p', 'b'], 1, 1, False, 'b']Failed
workspace regression 5[['a', 'c'], ['p', 'b'], 1, 1, False, 'a'][['a', 'c'], ['p', 'b'], 1, 2, False, 'a']Failed

SHA-256 / 4cc1a0a56d70edc77a6461f7655aee524412f299db14c80384fdb31b68648b63

HELD IN THE MEMBER ARCHIVE

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

This mechanism has 6 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.

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Verification & scope

Finite stipulated workspace snapshots only. Independent result fields describe observable obligations, not a full UI runtime. 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 2026-09-29T14:42:47.223241+00:00.

Case digest / 59f58c9bdc62a7f886d4d6833f44450d73a256d23038b81390a494e71c3a9bf2