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FA-36196 / Tab interfaces / Open access

Multi tab drag: drag anchor retention · case 01

The tab workspace reports an incorrect drag anchor retention.

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

ROOT CAUSE

The drag anchor retention decision uses x['selected'][0] instead of x['anchor'].

VERIFIED REPAIR

Use the stipulated workspace rule: x['anchor'].

Unsuccessful approach: The partial repair x['selected'][-1] still violates a workspace boundary or normal case.

Case contract

Dragging a selected set keeps its visual order, rebases drop boundary by every moved item before it, preserves anchor view and leaves unselected tabs ordered.

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['tabs'] if t in x['selected']]
    r1 = [t for t in x['tabs'] if t not in x['selected']]
    r2 = x['boundary']-sum(t in x['selected'] for t in x['tabs'][:x['boundary']])
    r3 = x['selected'][0]
    r4 = [t for t in x['tabs'] if t in x['selected']].index(x['anchor'])
    r5 = list(range(x['boundary']-sum(t in x['selected'] for t in x['tabs'][:x['boundary']]),x['boundary']-sum(t in x['selected'] for t in x['tabs'][:x['boundary']])+len(x['selected'])))
    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': ['a', 'b', 'c', 'd', 'e'], 'selected': ['b', 'd'], 'boundary': 5, 'anchor': 'd'}, [['b', 'd'], ['a', 'c', 'e'], 3, 'd', 1, [3, 4]]), ({'tabs': ['a', 'b', 'c', 'd', 'e'], 'selected': ['d', 'b'], 'boundary': 5, 'anchor': 'd'}, [['b', 'd'], ['a', 'c', 'e'], 3, 'd', 1, [3, 4]]), ({'tabs': ['a', 'b', 'c', 'd', 'e'], 'selected': ['b', 'd'], 'boundary': 2, 'anchor': 'd'}, [['b', 'd'], ['a', 'c', 'e'], 1, 'd', 1, [1, 2]]), ({'tabs': ['a', 'b', 'c', 'd', 'e'], 'selected': ['a', 'b'], 'boundary': 5, 'anchor': 'a'}, [['a', 'b'], ['c', 'd', 'e'], 3, 'a', 0, [3, 4]]), ({'tabs': ['a', 'b', 'c', 'd', 'e'], 'selected': ['b', 'd'], 'boundary': 5, 'anchor': 'b'}, [['b', 'd'], ['a', 'c', 'e'], 3, 'b', 0, [3, 4]]), ({'tabs': ['a', 'b', 'c', 'd', 'e'], 'selected': ['b', 'd'], 'boundary': 0, 'anchor': 'd'}, [['b', 'd'], ['a', 'c', 'e'], 0, 'd', 1, [0, 1]])], 2: [({'tabs': ['a', 'b', 'c', 'd', 'e', 'background0'], 'selected': ['b', 'd'], 'boundary': 5, 'anchor': 'd'}, [['b', 'd'], ['a', 'c', 'e', 'background0'], 3, 'd', 1, [3, 4]]), ({'tabs': ['a', 'b', 'c', 'd', 'e', 'background0'], 'selected': ['d', 'b'], 'boundary': 5, 'anchor': 'd'}, [['b', 'd'], ['a', 'c', 'e', 'background0'], 3, 'd', 1, [3, 4]]), ({'tabs': ['a', 'b', 'c', 'd', 'e', 'background0'], 'selected': ['b', 'd'], 'boundary': 2, 'anchor': 'd'}, [['b', 'd'], ['a', 'c', 'e', 'background0'], 1, 'd', 1, [1, 2]]), ({'tabs': ['a', 'b', 'c', 'd', 'e', 'background0'], 'selected': ['a', 'b'], 'boundary': 5, 'anchor': 'a'}, [['a', 'b'], ['c', 'd', 'e', 'background0'], 3, 'a', 0, [3, 4]]), ({'tabs': ['a', 'b', 'c', 'd', 'e', 'background0'], 'selected': ['b', 'd'], 'boundary': 5, 'anchor': 'b'}, [['b', 'd'], ['a', 'c', 'e', 'background0'], 3, 'b', 0, [3, 4]]), ({'tabs': ['a', 'b', 'c', 'd', 'e', 'background0'], 'selected': ['b', 'd'], 'boundary': 0, 'anchor': 'd'}, [['b', 'd'], ['a', 'c', 'e', 'background0'], 0, 'd', 1, [0, 1]])], 3: [({'tabs': ['a', 'b', 'c', 'd', 'e', 'background0', 'background1'], 'selected': ['b', 'd'], 'boundary': 5, 'anchor': 'd'}, [['b', 'd'], ['a', 'c', 'e', 'background0', 'background1'], 3, 'd', 1, [3, 4]]), ({'tabs': ['a', 'b', 'c', 'd', 'e', 'background0', 'background1'], 'selected': ['d', 'b'], 'boundary': 5, 'anchor': 'd'}, [['b', 'd'], ['a', 'c', 'e', 'background0', 'background1'], 3, 'd', 1, [3, 4]]), ({'tabs': ['a', 'b', 'c', 'd', 'e', 'background0', 'background1'], 'selected': ['b', 'd'], 'boundary': 2, 'anchor': 'd'}, [['b', 'd'], ['a', 'c', 'e', 'background0', 'background1'], 1, 'd', 1, [1, 2]]), ({'tabs': ['a', 'b', 'c', 'd', 'e', 'background0', 'background1'], 'selected': ['a', 'b'], 'boundary': 5, 'anchor': 'a'}, [['a', 'b'], ['c', 'd', 'e', 'background0', 'background1'], 3, 'a', 0, [3, 4]]), ({'tabs': ['a', 'b', 'c', 'd', 'e', 'background0', 'background1'], 'selected': ['b', 'd'], 'boundary': 5, 'anchor': 'b'}, [['b', 'd'], ['a', 'c', 'e', 'background0', 'background1'], 3, 'b', 0, [3, 4]]), ({'tabs': ['a', 'b', 'c', 'd', 'e', 'background0', 'background1'], 'selected': ['b', 'd'], 'boundary': 0, 'anchor': 'd'}, [['b', 'd'], ['a', 'c', 'e', 'background0', 'background1'], 0, 'd', 1, [0, 1]])], 4: [({'tabs': ['a', 'b', 'c', 'd', 'e', 'background0', 'background1', 'background2'], 'selected': ['b', 'd'], 'boundary': 5, 'anchor': 'd'}, [['b', 'd'], ['a', 'c', 'e', 'background0', 'background1', 'background2'], 3, 'd', 1, [3, 4]]), ({'tabs': ['a', 'b', 'c', 'd', 'e', 'background0', 'background1', 'background2'], 'selected': ['d', 'b'], 'boundary': 5, 'anchor': 'd'}, [['b', 'd'], ['a', 'c', 'e', 'background0', 'background1', 'background2'], 3, 'd', 1, [3, 4]]), ({'tabs': ['a', 'b', 'c', 'd', 'e', 'background0', 'background1', 'background2'], 'selected': ['b', 'd'], 'boundary': 2, 'anchor': 'd'}, [['b', 'd'], ['a', 'c', 'e', 'background0', 'background1', 'background2'], 1, 'd', 1, [1, 2]]), ({'tabs': ['a', 'b', 'c', 'd', 'e', 'background0', 'background1', 'background2'], 'selected': ['a', 'b'], 'boundary': 5, 'anchor': 'a'}, [['a', 'b'], ['c', 'd', 'e', 'background0', 'background1', 'background2'], 3, 'a', 0, [3, 4]]), ({'tabs': ['a', 'b', 'c', 'd', 'e', 'background0', 'background1', 'background2'], 'selected': ['b', 'd'], 'boundary': 5, 'anchor': 'b'}, [['b', 'd'], ['a', 'c', 'e', 'background0', 'background1', 'background2'], 3, 'b', 0, [3, 4]]), ({'tabs': ['a', 'b', 'c', 'd', 'e', 'background0', 'background1', 'background2'], 'selected': ['b', 'd'], 'boundary': 0, 'anchor': 'd'}, [['b', 'd'], ['a', 'c', 'e', 'background0', 'background1', 'background2'], 0, 'd', 1, [0, 1]])], 5: [({'tabs': ['a', 'b', 'c', 'd', 'e', 'background0', 'background1', 'background2', 'background3'], 'selected': ['b', 'd'], 'boundary': 5, 'anchor': 'd'}, [['b', 'd'], ['a', 'c', 'e', 'background0', 'background1', 'background2', 'background3'], 3, 'd', 1, [3, 4]]), ({'tabs': ['a', 'b', 'c', 'd', 'e', 'background0', 'background1', 'background2', 'background3'], 'selected': ['d', 'b'], 'boundary': 5, 'anchor': 'd'}, [['b', 'd'], ['a', 'c', 'e', 'background0', 'background1', 'background2', 'background3'], 3, 'd', 1, [3, 4]]), ({'tabs': ['a', 'b', 'c', 'd', 'e', 'background0', 'background1', 'background2', 'background3'], 'selected': ['b', 'd'], 'boundary': 2, 'anchor': 'd'}, [['b', 'd'], ['a', 'c', 'e', 'background0', 'background1', 'background2', 'background3'], 1, 'd', 1, [1, 2]]), ({'tabs': ['a', 'b', 'c', 'd', 'e', 'background0', 'background1', 'background2', 'background3'], 'selected': ['a', 'b'], 'boundary': 5, 'anchor': 'a'}, [['a', 'b'], ['c', 'd', 'e', 'background0', 'background1', 'background2', 'background3'], 3, 'a', 0, [3, 4]]), ({'tabs': ['a', 'b', 'c', 'd', 'e', 'background0', 'background1', 'background2', 'background3'], 'selected': ['b', 'd'], 'boundary': 5, 'anchor': 'b'}, [['b', 'd'], ['a', 'c', 'e', 'background0', 'background1', 'background2', 'background3'], 3, 'b', 0, [3, 4]]), ({'tabs': ['a', 'b', 'c', 'd', 'e', 'background0', 'background1', 'background2', 'background3'], 'selected': ['b', 'd'], 'boundary': 0, 'anchor': 'd'}, [['b', 'd'], ['a', 'c', 'e', 'background0', 'background1', 'background2', 'background3'], 0, 'd', 1, [0, 1]])]}
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[['b', 'd'], ['a', 'c', 'e'], 3, 'b', 1, [3, 4]][['b', 'd'], ['a', 'c', 'e'], 3, 'd', 1, [3, 4]]Failed
workspace regression 1[['b', 'd'], ['a', 'c', 'e'], 3, 'd', 1, [3, 4]][['b', 'd'], ['a', 'c', 'e'], 3, 'd', 1, [3, 4]]Passed
workspace regression 2[['b', 'd'], ['a', 'c', 'e'], 1, 'b', 1, [1, 2]][['b', 'd'], ['a', 'c', 'e'], 1, 'd', 1, [1, 2]]Failed
workspace regression 3[['a', 'b'], ['c', 'd', 'e'], 3, 'a', 0, [3, 4]][['a', 'b'], ['c', 'd', 'e'], 3, 'a', 0, [3, 4]]Passed
workspace regression 4[['b', 'd'], ['a', 'c', 'e'], 3, 'b', 0, [3, 4]][['b', 'd'], ['a', 'c', 'e'], 3, 'b', 0, [3, 4]]Passed
workspace regression 5[['b', 'd'], ['a', 'c', 'e'], 0, 'b', 1, [0, 1]][['b', 'd'], ['a', 'c', 'e'], 0, 'd', 1, [0, 1]]Failed

SHA-256 / 435a9b375b4df44d8761eeb25abb616cb76d578b370af138a9cb775b09bfb376

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['tabs'] if t in x['selected']]
    r1 = [t for t in x['tabs'] if t not in x['selected']]
    r2 = x['boundary']-sum(t in x['selected'] for t in x['tabs'][:x['boundary']])
    r3 = x['selected'][-1]
    r4 = [t for t in x['tabs'] if t in x['selected']].index(x['anchor'])
    r5 = list(range(x['boundary']-sum(t in x['selected'] for t in x['tabs'][:x['boundary']]),x['boundary']-sum(t in x['selected'] for t in x['tabs'][:x['boundary']])+len(x['selected'])))
    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': ['a', 'b', 'c', 'd', 'e'], 'selected': ['b', 'd'], 'boundary': 5, 'anchor': 'd'}, [['b', 'd'], ['a', 'c', 'e'], 3, 'd', 1, [3, 4]]), ({'tabs': ['a', 'b', 'c', 'd', 'e'], 'selected': ['d', 'b'], 'boundary': 5, 'anchor': 'd'}, [['b', 'd'], ['a', 'c', 'e'], 3, 'd', 1, [3, 4]]), ({'tabs': ['a', 'b', 'c', 'd', 'e'], 'selected': ['b', 'd'], 'boundary': 2, 'anchor': 'd'}, [['b', 'd'], ['a', 'c', 'e'], 1, 'd', 1, [1, 2]]), ({'tabs': ['a', 'b', 'c', 'd', 'e'], 'selected': ['a', 'b'], 'boundary': 5, 'anchor': 'a'}, [['a', 'b'], ['c', 'd', 'e'], 3, 'a', 0, [3, 4]]), ({'tabs': ['a', 'b', 'c', 'd', 'e'], 'selected': ['b', 'd'], 'boundary': 5, 'anchor': 'b'}, [['b', 'd'], ['a', 'c', 'e'], 3, 'b', 0, [3, 4]]), ({'tabs': ['a', 'b', 'c', 'd', 'e'], 'selected': ['b', 'd'], 'boundary': 0, 'anchor': 'd'}, [['b', 'd'], ['a', 'c', 'e'], 0, 'd', 1, [0, 1]])], 2: [({'tabs': ['a', 'b', 'c', 'd', 'e', 'background0'], 'selected': ['b', 'd'], 'boundary': 5, 'anchor': 'd'}, [['b', 'd'], ['a', 'c', 'e', 'background0'], 3, 'd', 1, [3, 4]]), ({'tabs': ['a', 'b', 'c', 'd', 'e', 'background0'], 'selected': ['d', 'b'], 'boundary': 5, 'anchor': 'd'}, [['b', 'd'], ['a', 'c', 'e', 'background0'], 3, 'd', 1, [3, 4]]), ({'tabs': ['a', 'b', 'c', 'd', 'e', 'background0'], 'selected': ['b', 'd'], 'boundary': 2, 'anchor': 'd'}, [['b', 'd'], ['a', 'c', 'e', 'background0'], 1, 'd', 1, [1, 2]]), ({'tabs': ['a', 'b', 'c', 'd', 'e', 'background0'], 'selected': ['a', 'b'], 'boundary': 5, 'anchor': 'a'}, [['a', 'b'], ['c', 'd', 'e', 'background0'], 3, 'a', 0, [3, 4]]), ({'tabs': ['a', 'b', 'c', 'd', 'e', 'background0'], 'selected': ['b', 'd'], 'boundary': 5, 'anchor': 'b'}, [['b', 'd'], ['a', 'c', 'e', 'background0'], 3, 'b', 0, [3, 4]]), ({'tabs': ['a', 'b', 'c', 'd', 'e', 'background0'], 'selected': ['b', 'd'], 'boundary': 0, 'anchor': 'd'}, [['b', 'd'], ['a', 'c', 'e', 'background0'], 0, 'd', 1, [0, 1]])], 3: [({'tabs': ['a', 'b', 'c', 'd', 'e', 'background0', 'background1'], 'selected': ['b', 'd'], 'boundary': 5, 'anchor': 'd'}, [['b', 'd'], ['a', 'c', 'e', 'background0', 'background1'], 3, 'd', 1, [3, 4]]), ({'tabs': ['a', 'b', 'c', 'd', 'e', 'background0', 'background1'], 'selected': ['d', 'b'], 'boundary': 5, 'anchor': 'd'}, [['b', 'd'], ['a', 'c', 'e', 'background0', 'background1'], 3, 'd', 1, [3, 4]]), ({'tabs': ['a', 'b', 'c', 'd', 'e', 'background0', 'background1'], 'selected': ['b', 'd'], 'boundary': 2, 'anchor': 'd'}, [['b', 'd'], ['a', 'c', 'e', 'background0', 'background1'], 1, 'd', 1, [1, 2]]), ({'tabs': ['a', 'b', 'c', 'd', 'e', 'background0', 'background1'], 'selected': ['a', 'b'], 'boundary': 5, 'anchor': 'a'}, [['a', 'b'], ['c', 'd', 'e', 'background0', 'background1'], 3, 'a', 0, [3, 4]]), ({'tabs': ['a', 'b', 'c', 'd', 'e', 'background0', 'background1'], 'selected': ['b', 'd'], 'boundary': 5, 'anchor': 'b'}, [['b', 'd'], ['a', 'c', 'e', 'background0', 'background1'], 3, 'b', 0, [3, 4]]), ({'tabs': ['a', 'b', 'c', 'd', 'e', 'background0', 'background1'], 'selected': ['b', 'd'], 'boundary': 0, 'anchor': 'd'}, [['b', 'd'], ['a', 'c', 'e', 'background0', 'background1'], 0, 'd', 1, [0, 1]])], 4: [({'tabs': ['a', 'b', 'c', 'd', 'e', 'background0', 'background1', 'background2'], 'selected': ['b', 'd'], 'boundary': 5, 'anchor': 'd'}, [['b', 'd'], ['a', 'c', 'e', 'background0', 'background1', 'background2'], 3, 'd', 1, [3, 4]]), ({'tabs': ['a', 'b', 'c', 'd', 'e', 'background0', 'background1', 'background2'], 'selected': ['d', 'b'], 'boundary': 5, 'anchor': 'd'}, [['b', 'd'], ['a', 'c', 'e', 'background0', 'background1', 'background2'], 3, 'd', 1, [3, 4]]), ({'tabs': ['a', 'b', 'c', 'd', 'e', 'background0', 'background1', 'background2'], 'selected': ['b', 'd'], 'boundary': 2, 'anchor': 'd'}, [['b', 'd'], ['a', 'c', 'e', 'background0', 'background1', 'background2'], 1, 'd', 1, [1, 2]]), ({'tabs': ['a', 'b', 'c', 'd', 'e', 'background0', 'background1', 'background2'], 'selected': ['a', 'b'], 'boundary': 5, 'anchor': 'a'}, [['a', 'b'], ['c', 'd', 'e', 'background0', 'background1', 'background2'], 3, 'a', 0, [3, 4]]), ({'tabs': ['a', 'b', 'c', 'd', 'e', 'background0', 'background1', 'background2'], 'selected': ['b', 'd'], 'boundary': 5, 'anchor': 'b'}, [['b', 'd'], ['a', 'c', 'e', 'background0', 'background1', 'background2'], 3, 'b', 0, [3, 4]]), ({'tabs': ['a', 'b', 'c', 'd', 'e', 'background0', 'background1', 'background2'], 'selected': ['b', 'd'], 'boundary': 0, 'anchor': 'd'}, [['b', 'd'], ['a', 'c', 'e', 'background0', 'background1', 'background2'], 0, 'd', 1, [0, 1]])], 5: [({'tabs': ['a', 'b', 'c', 'd', 'e', 'background0', 'background1', 'background2', 'background3'], 'selected': ['b', 'd'], 'boundary': 5, 'anchor': 'd'}, [['b', 'd'], ['a', 'c', 'e', 'background0', 'background1', 'background2', 'background3'], 3, 'd', 1, [3, 4]]), ({'tabs': ['a', 'b', 'c', 'd', 'e', 'background0', 'background1', 'background2', 'background3'], 'selected': ['d', 'b'], 'boundary': 5, 'anchor': 'd'}, [['b', 'd'], ['a', 'c', 'e', 'background0', 'background1', 'background2', 'background3'], 3, 'd', 1, [3, 4]]), ({'tabs': ['a', 'b', 'c', 'd', 'e', 'background0', 'background1', 'background2', 'background3'], 'selected': ['b', 'd'], 'boundary': 2, 'anchor': 'd'}, [['b', 'd'], ['a', 'c', 'e', 'background0', 'background1', 'background2', 'background3'], 1, 'd', 1, [1, 2]]), ({'tabs': ['a', 'b', 'c', 'd', 'e', 'background0', 'background1', 'background2', 'background3'], 'selected': ['a', 'b'], 'boundary': 5, 'anchor': 'a'}, [['a', 'b'], ['c', 'd', 'e', 'background0', 'background1', 'background2', 'background3'], 3, 'a', 0, [3, 4]]), ({'tabs': ['a', 'b', 'c', 'd', 'e', 'background0', 'background1', 'background2', 'background3'], 'selected': ['b', 'd'], 'boundary': 5, 'anchor': 'b'}, [['b', 'd'], ['a', 'c', 'e', 'background0', 'background1', 'background2', 'background3'], 3, 'b', 0, [3, 4]]), ({'tabs': ['a', 'b', 'c', 'd', 'e', 'background0', 'background1', 'background2', 'background3'], 'selected': ['b', 'd'], 'boundary': 0, 'anchor': 'd'}, [['b', 'd'], ['a', 'c', 'e', 'background0', 'background1', 'background2', 'background3'], 0, 'd', 1, [0, 1]])]}
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[['b', 'd'], ['a', 'c', 'e'], 3, 'd', 1, [3, 4]][['b', 'd'], ['a', 'c', 'e'], 3, 'd', 1, [3, 4]]Passed
workspace regression 1[['b', 'd'], ['a', 'c', 'e'], 3, 'b', 1, [3, 4]][['b', 'd'], ['a', 'c', 'e'], 3, 'd', 1, [3, 4]]Failed
workspace regression 2[['b', 'd'], ['a', 'c', 'e'], 1, 'd', 1, [1, 2]][['b', 'd'], ['a', 'c', 'e'], 1, 'd', 1, [1, 2]]Passed
workspace regression 3[['a', 'b'], ['c', 'd', 'e'], 3, 'b', 0, [3, 4]][['a', 'b'], ['c', 'd', 'e'], 3, 'a', 0, [3, 4]]Failed
workspace regression 4[['b', 'd'], ['a', 'c', 'e'], 3, 'd', 0, [3, 4]][['b', 'd'], ['a', 'c', 'e'], 3, 'b', 0, [3, 4]]Failed
workspace regression 5[['b', 'd'], ['a', 'c', 'e'], 0, 'd', 1, [0, 1]][['b', 'd'], ['a', 'c', 'e'], 0, 'd', 1, [0, 1]]Passed

SHA-256 / 03ecf1671b9b5d276dd51f611644d93710b593bf7226a7c72d9fa1118b6091a4

3 / The verified repair

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

N = 1
observations = []
def solve(x):
    r0 = [t for t in x['tabs'] if t in x['selected']]
    r1 = [t for t in x['tabs'] if t not in x['selected']]
    r2 = x['boundary']-sum(t in x['selected'] for t in x['tabs'][:x['boundary']])
    r3 = x['anchor']
    r4 = [t for t in x['tabs'] if t in x['selected']].index(x['anchor'])
    r5 = list(range(x['boundary']-sum(t in x['selected'] for t in x['tabs'][:x['boundary']]),x['boundary']-sum(t in x['selected'] for t in x['tabs'][:x['boundary']])+len(x['selected'])))
    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': ['a', 'b', 'c', 'd', 'e'], 'selected': ['b', 'd'], 'boundary': 5, 'anchor': 'd'}, [['b', 'd'], ['a', 'c', 'e'], 3, 'd', 1, [3, 4]]), ({'tabs': ['a', 'b', 'c', 'd', 'e'], 'selected': ['d', 'b'], 'boundary': 5, 'anchor': 'd'}, [['b', 'd'], ['a', 'c', 'e'], 3, 'd', 1, [3, 4]]), ({'tabs': ['a', 'b', 'c', 'd', 'e'], 'selected': ['b', 'd'], 'boundary': 2, 'anchor': 'd'}, [['b', 'd'], ['a', 'c', 'e'], 1, 'd', 1, [1, 2]]), ({'tabs': ['a', 'b', 'c', 'd', 'e'], 'selected': ['a', 'b'], 'boundary': 5, 'anchor': 'a'}, [['a', 'b'], ['c', 'd', 'e'], 3, 'a', 0, [3, 4]]), ({'tabs': ['a', 'b', 'c', 'd', 'e'], 'selected': ['b', 'd'], 'boundary': 5, 'anchor': 'b'}, [['b', 'd'], ['a', 'c', 'e'], 3, 'b', 0, [3, 4]]), ({'tabs': ['a', 'b', 'c', 'd', 'e'], 'selected': ['b', 'd'], 'boundary': 0, 'anchor': 'd'}, [['b', 'd'], ['a', 'c', 'e'], 0, 'd', 1, [0, 1]])], 2: [({'tabs': ['a', 'b', 'c', 'd', 'e', 'background0'], 'selected': ['b', 'd'], 'boundary': 5, 'anchor': 'd'}, [['b', 'd'], ['a', 'c', 'e', 'background0'], 3, 'd', 1, [3, 4]]), ({'tabs': ['a', 'b', 'c', 'd', 'e', 'background0'], 'selected': ['d', 'b'], 'boundary': 5, 'anchor': 'd'}, [['b', 'd'], ['a', 'c', 'e', 'background0'], 3, 'd', 1, [3, 4]]), ({'tabs': ['a', 'b', 'c', 'd', 'e', 'background0'], 'selected': ['b', 'd'], 'boundary': 2, 'anchor': 'd'}, [['b', 'd'], ['a', 'c', 'e', 'background0'], 1, 'd', 1, [1, 2]]), ({'tabs': ['a', 'b', 'c', 'd', 'e', 'background0'], 'selected': ['a', 'b'], 'boundary': 5, 'anchor': 'a'}, [['a', 'b'], ['c', 'd', 'e', 'background0'], 3, 'a', 0, [3, 4]]), ({'tabs': ['a', 'b', 'c', 'd', 'e', 'background0'], 'selected': ['b', 'd'], 'boundary': 5, 'anchor': 'b'}, [['b', 'd'], ['a', 'c', 'e', 'background0'], 3, 'b', 0, [3, 4]]), ({'tabs': ['a', 'b', 'c', 'd', 'e', 'background0'], 'selected': ['b', 'd'], 'boundary': 0, 'anchor': 'd'}, [['b', 'd'], ['a', 'c', 'e', 'background0'], 0, 'd', 1, [0, 1]])], 3: [({'tabs': ['a', 'b', 'c', 'd', 'e', 'background0', 'background1'], 'selected': ['b', 'd'], 'boundary': 5, 'anchor': 'd'}, [['b', 'd'], ['a', 'c', 'e', 'background0', 'background1'], 3, 'd', 1, [3, 4]]), ({'tabs': ['a', 'b', 'c', 'd', 'e', 'background0', 'background1'], 'selected': ['d', 'b'], 'boundary': 5, 'anchor': 'd'}, [['b', 'd'], ['a', 'c', 'e', 'background0', 'background1'], 3, 'd', 1, [3, 4]]), ({'tabs': ['a', 'b', 'c', 'd', 'e', 'background0', 'background1'], 'selected': ['b', 'd'], 'boundary': 2, 'anchor': 'd'}, [['b', 'd'], ['a', 'c', 'e', 'background0', 'background1'], 1, 'd', 1, [1, 2]]), ({'tabs': ['a', 'b', 'c', 'd', 'e', 'background0', 'background1'], 'selected': ['a', 'b'], 'boundary': 5, 'anchor': 'a'}, [['a', 'b'], ['c', 'd', 'e', 'background0', 'background1'], 3, 'a', 0, [3, 4]]), ({'tabs': ['a', 'b', 'c', 'd', 'e', 'background0', 'background1'], 'selected': ['b', 'd'], 'boundary': 5, 'anchor': 'b'}, [['b', 'd'], ['a', 'c', 'e', 'background0', 'background1'], 3, 'b', 0, [3, 4]]), ({'tabs': ['a', 'b', 'c', 'd', 'e', 'background0', 'background1'], 'selected': ['b', 'd'], 'boundary': 0, 'anchor': 'd'}, [['b', 'd'], ['a', 'c', 'e', 'background0', 'background1'], 0, 'd', 1, [0, 1]])], 4: [({'tabs': ['a', 'b', 'c', 'd', 'e', 'background0', 'background1', 'background2'], 'selected': ['b', 'd'], 'boundary': 5, 'anchor': 'd'}, [['b', 'd'], ['a', 'c', 'e', 'background0', 'background1', 'background2'], 3, 'd', 1, [3, 4]]), ({'tabs': ['a', 'b', 'c', 'd', 'e', 'background0', 'background1', 'background2'], 'selected': ['d', 'b'], 'boundary': 5, 'anchor': 'd'}, [['b', 'd'], ['a', 'c', 'e', 'background0', 'background1', 'background2'], 3, 'd', 1, [3, 4]]), ({'tabs': ['a', 'b', 'c', 'd', 'e', 'background0', 'background1', 'background2'], 'selected': ['b', 'd'], 'boundary': 2, 'anchor': 'd'}, [['b', 'd'], ['a', 'c', 'e', 'background0', 'background1', 'background2'], 1, 'd', 1, [1, 2]]), ({'tabs': ['a', 'b', 'c', 'd', 'e', 'background0', 'background1', 'background2'], 'selected': ['a', 'b'], 'boundary': 5, 'anchor': 'a'}, [['a', 'b'], ['c', 'd', 'e', 'background0', 'background1', 'background2'], 3, 'a', 0, [3, 4]]), ({'tabs': ['a', 'b', 'c', 'd', 'e', 'background0', 'background1', 'background2'], 'selected': ['b', 'd'], 'boundary': 5, 'anchor': 'b'}, [['b', 'd'], ['a', 'c', 'e', 'background0', 'background1', 'background2'], 3, 'b', 0, [3, 4]]), ({'tabs': ['a', 'b', 'c', 'd', 'e', 'background0', 'background1', 'background2'], 'selected': ['b', 'd'], 'boundary': 0, 'anchor': 'd'}, [['b', 'd'], ['a', 'c', 'e', 'background0', 'background1', 'background2'], 0, 'd', 1, [0, 1]])], 5: [({'tabs': ['a', 'b', 'c', 'd', 'e', 'background0', 'background1', 'background2', 'background3'], 'selected': ['b', 'd'], 'boundary': 5, 'anchor': 'd'}, [['b', 'd'], ['a', 'c', 'e', 'background0', 'background1', 'background2', 'background3'], 3, 'd', 1, [3, 4]]), ({'tabs': ['a', 'b', 'c', 'd', 'e', 'background0', 'background1', 'background2', 'background3'], 'selected': ['d', 'b'], 'boundary': 5, 'anchor': 'd'}, [['b', 'd'], ['a', 'c', 'e', 'background0', 'background1', 'background2', 'background3'], 3, 'd', 1, [3, 4]]), ({'tabs': ['a', 'b', 'c', 'd', 'e', 'background0', 'background1', 'background2', 'background3'], 'selected': ['b', 'd'], 'boundary': 2, 'anchor': 'd'}, [['b', 'd'], ['a', 'c', 'e', 'background0', 'background1', 'background2', 'background3'], 1, 'd', 1, [1, 2]]), ({'tabs': ['a', 'b', 'c', 'd', 'e', 'background0', 'background1', 'background2', 'background3'], 'selected': ['a', 'b'], 'boundary': 5, 'anchor': 'a'}, [['a', 'b'], ['c', 'd', 'e', 'background0', 'background1', 'background2', 'background3'], 3, 'a', 0, [3, 4]]), ({'tabs': ['a', 'b', 'c', 'd', 'e', 'background0', 'background1', 'background2', 'background3'], 'selected': ['b', 'd'], 'boundary': 5, 'anchor': 'b'}, [['b', 'd'], ['a', 'c', 'e', 'background0', 'background1', 'background2', 'background3'], 3, 'b', 0, [3, 4]]), ({'tabs': ['a', 'b', 'c', 'd', 'e', 'background0', 'background1', 'background2', 'background3'], 'selected': ['b', 'd'], 'boundary': 0, 'anchor': 'd'}, [['b', 'd'], ['a', 'c', 'e', 'background0', 'background1', 'background2', 'background3'], 0, 'd', 1, [0, 1]])]}
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[['b', 'd'], ['a', 'c', 'e'], 3, 'd', 1, [3, 4]][['b', 'd'], ['a', 'c', 'e'], 3, 'd', 1, [3, 4]]Passed
workspace regression 1[['b', 'd'], ['a', 'c', 'e'], 3, 'd', 1, [3, 4]][['b', 'd'], ['a', 'c', 'e'], 3, 'd', 1, [3, 4]]Passed
workspace regression 2[['b', 'd'], ['a', 'c', 'e'], 1, 'd', 1, [1, 2]][['b', 'd'], ['a', 'c', 'e'], 1, 'd', 1, [1, 2]]Passed
workspace regression 3[['a', 'b'], ['c', 'd', 'e'], 3, 'a', 0, [3, 4]][['a', 'b'], ['c', 'd', 'e'], 3, 'a', 0, [3, 4]]Passed
workspace regression 4[['b', 'd'], ['a', 'c', 'e'], 3, 'b', 0, [3, 4]][['b', 'd'], ['a', 'c', 'e'], 3, 'b', 0, [3, 4]]Passed
workspace regression 5[['b', 'd'], ['a', 'c', 'e'], 0, 'd', 1, [0, 1]][['b', 'd'], ['a', 'c', 'e'], 0, 'd', 1, [0, 1]]Passed

SHA-256 / a2ab14e01534687e9120f90715aeac8fb0416f22bc248832d319201dbbdea747

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 2026-09-29T14:42:48.914408+00:00.

Case digest / c71966919e731cfd885df3e32407c410099e78972235b2e7fb4157ba7248e09e