test262 built-ins/Array — 68 fails (exotic length/index, prototype-as-receiver)

[proggeramlug]

Current state — 68 failing. Snapshot from the 2026-06-28 full sweep (perry 0.5.1207, node v26.3.0). Supersedes the original body; the complete current failing-test list is inline below — no re-run needed to start.

Array exotic-object length/index coupling, Array.prototype.* with a non-array receiver, iterator done-flag. Some (no output) need per-case look.

Failure reasons

n	reason
13	Uncaught exception: Expected a TypeError to be thrown but no exception
10	(no output)
4	Uncaught exception: #1: Array.prototype[1] = 1; x = [0]; x.length = 2;
3	Uncaught exception: x.toString() must return "[object Array]" Expected
3	Uncaught exception: Exhausted result 'done' flag (after push) Expected
3	Uncaught exception: #3: var obj = {}; obj.reverse = Array.prototype.re
2	Uncaught exception: The value of value is expected to equal the value
2	Uncaught exception: Expected SameValue(«"Bike"», «undefined») to be tr
2	Uncaught exception: f.reduceRight(cb,"4") Expected SameValue(«"4undefi
2	Uncaught exception: Expected SameValue(«"true,false"», «"boolean,boole
1	Uncaught exception: The value of Array.myproperty is expected to be 1
1	Uncaught exception: The value of x[k - 2] is expected to equal the val

All 68 failing tests (path — reason)

full list — click to expand

built-ins/Array/S15.4.1_A1.1_T2.js    Uncaught exception: x.toString() must return "[object Array]" Expected SameValue(«""», «"[
built-ins/Array/S15.4.2.1_A1.1_T2.js    Uncaught exception: x.toString() must return "[object Array]" Expected SameValue(«""», «"[
built-ins/Array/S15.4.3_A1.1_T1.js    Uncaught exception: The value of Array.myproperty is expected to be 1 Expected SameValue(«
built-ins/Array/S15.4.5.2_A3_T3.js    (no output)
built-ins/Array/S15.4_A1.1_T10.js    Uncaught exception: The value of x[k - 2] is expected to equal the value of k Expected Sam
built-ins/Array/from/elements-deleted-after.js    Uncaught exception: The value of value is expected to equal the value of array[this.arrayI
built-ins/Array/from/source-array-boundary.js    Uncaught exception: The value of value is expected to equal the value of array[this.arrayI
built-ins/Array/length/15.4.5.1-3.d-3.js    (no output)
built-ins/Array/length/S15.4.2.2_A1.1_T2.js    Uncaught exception: x.toString() must return "[object Array]" Expected SameValue(«""», «"[
built-ins/Array/length/S15.4.2.2_A2.1_T1.js    (no output)
built-ins/Array/length/S15.4.5.2_A3_T4.js    (no output)
built-ins/Array/of/return-a-new-array-object.js    Uncaught exception: The result of evaluating (result instanceof Array) is expected to be t
built-ins/Array/of/return-abrupt-from-data-property-using-proxy.js    (no output)
built-ins/Array/prototype/Symbol.iterator.js    Uncaught exception: Expected SameValue(«function () { [native code] }», «function () { [na
built-ins/Array/prototype/entries/iteration-mutable.js    Uncaught exception: Exhausted result `done` flag (after push) Expected SameValue(«false», 
built-ins/Array/prototype/filter/15.4.4.20-9-b-6.js    Uncaught exception: Array[1] Expected SameValue(«undefined», «6.99») to be true
built-ins/Array/prototype/find/array-altered-during-loop.js    Uncaught exception: Expected SameValue(«"Bike"», «undefined») to be true
built-ins/Array/prototype/findIndex/array-altered-during-loop.js    Uncaught exception: Expected SameValue(«"Bike"», «undefined») to be true
built-ins/Array/prototype/indexOf/15.4.4.14-9-9.js    Uncaught exception: a.indexOf(2,4294967290 ) Expected SameValue(«-2», «4294967294») to be 
built-ins/Array/prototype/join/S15.4.4.5_A5_T1.js    Uncaught exception: #1: Array.prototype[1] = 1; x = [0]; x.length = 2; x.join() === "0,1".
built-ins/Array/prototype/keys/iteration-mutable.js    Uncaught exception: Exhausted result `done` flag (after push) Expected SameValue(«false», 
built-ins/Array/prototype/lastIndexOf/15.4.4.15-5-12.js    Uncaught exception: arr.lastIndexOf(null, Infinity) Expected SameValue(«-2», «4294967294»)
built-ins/Array/prototype/lastIndexOf/15.4.4.15-5-16.js    Uncaught exception: arr.lastIndexOf(true, "Infinity") Expected SameValue(«-2», «4294967294
built-ins/Array/prototype/lastIndexOf/15.4.4.15-8-9.js    Uncaught exception: a.lastIndexOf(2) Expected SameValue(«-2», «4294967294») to be true
built-ins/Array/prototype/pop/S15.4.4.6_A4_T1.js    Uncaught exception: #1: Array.prototype[1] = 1; x = [0]; x.length = 2; x.pop() === 1. Actu
built-ins/Array/prototype/pop/set-length-array-is-frozen.js    Uncaught exception: Expected a TypeError to be thrown but no exception was thrown at all
built-ins/Array/prototype/pop/set-length-array-length-is-non-writable.js    Uncaught exception: Expected a TypeError to be thrown but no exception was thrown at all
built-ins/Array/prototype/push/S15.4.4.7_A2_T2.js    Uncaught exception: Expected a TypeError to be thrown but no exception was thrown at all
built-ins/Array/prototype/push/S15.4.4.7_A3.js    (no output)
built-ins/Array/prototype/push/set-length-array-is-frozen.js    Uncaught exception: Expected a TypeError to be thrown but no exception was thrown at all
built-ins/Array/prototype/push/set-length-array-length-is-non-writable.js    Uncaught exception: Expected a TypeError to be thrown but no exception was thrown at all
built-ins/Array/prototype/push/set-length-zero-array-is-frozen.js    Uncaught exception: Expected a TypeError to be thrown but no exception was thrown at all
built-ins/Array/prototype/push/set-length-zero-array-length-is-non-writable.js    Uncaught exception: Expected a TypeError to be thrown but no exception was thrown at all
built-ins/Array/prototype/reduce/15.4.4.21-10-3.js    Uncaught exception: f.reduce(cb) Expected SameValue(«undefined», «1») to be true
built-ins/Array/prototype/reduce/15.4.4.21-10-4.js    Uncaught exception: f.reduce(cb) Expected SameValue(«NaN», «10») to be true
built-ins/Array/prototype/reduce/15.4.4.21-10-6.js    Uncaught exception: f.reduce(cb,-1) Expected SameValue(«NaN», «9») to be true
built-ins/Array/prototype/reduce/15.4.4.21-10-7.js    Uncaught exception: f.reduce(cb,-1) Expected SameValue(«NaN», «0») to be true
built-ins/Array/prototype/reduceRight/15.4.4.22-10-3.js    Uncaught exception: f.reduceRight(cb) Expected SameValue(«undefined», «1») to be true
built-ins/Array/prototype/reduceRight/15.4.4.22-10-4.js    Uncaught exception: f.reduceRight(cb) Expected SameValue(«NaN», «6») to be true
built-ins/Array/prototype/reduceRight/15.4.4.22-10-6.js    Uncaught exception: f.reduceRight(cb,"4") Expected SameValue(«"4undefinedundefinedundefine
built-ins/Array/prototype/reduceRight/15.4.4.22-10-7.js    Uncaught exception: f.reduceRight(cb,"4") Expected SameValue(«"4undefined"», «"41"») to be
built-ins/Array/prototype/reduceRight/15.4.4.22-8-b-iii-1-30.js    Uncaught exception: testResult !== true
built-ins/Array/prototype/reverse/S15.4.4.8_A2_T1.js    Uncaught exception: #3: var obj = {}; obj.reverse = Array.prototype.reverse; obj.length = 
built-ins/Array/prototype/reverse/S15.4.4.8_A2_T2.js    Uncaught exception: #3: var obj = {}; obj.reverse = Array.prototype.reverse; obj.length = 
built-ins/Array/prototype/reverse/S15.4.4.8_A2_T3.js    Uncaught exception: #3: var obj = {}; obj.reverse = Array.prototype.reverse; obj.length = 
built-ins/Array/prototype/reverse/S15.4.4.8_A4_T1.js    Uncaught exception: #1: Array.prototype[1] = 1; x = [0]; x.length = 2; x.reverse(); x[0] =
built-ins/Array/prototype/reverse/get_if_present_with_delete.js    Uncaught exception: Indexed property '0' not present Expected SameValue(«true», «false») t
built-ins/Array/prototype/shift/S15.4.4.9_A1.2_T1.js    Uncaught exception: #9: x = []; x[0] = 0; x[3] = 3; x.shift(); x.length = 1; x.shift() ===
built-ins/Array/prototype/shift/S15.4.4.9_A4_T1.js    Uncaught exception: #2: Array.prototype[1] = 1; x = [0]; x.length = 2; x.shift(); x[0] ===
built-ins/Array/prototype/shift/set-length-array-is-frozen.js    Uncaught exception: Expected a TypeError to be thrown but no exception was thrown at all
built-ins/Array/prototype/shift/set-length-array-length-is-non-writable.js    Uncaught exception: Expected a TypeError to be thrown but no exception was thrown at all
built-ins/Array/prototype/shift/throws-when-this-value-length-is-writable-false.js    Uncaught exception: Array.prototype.shift.call(function() {}) Expected a TypeError to be t
built-ins/Array/prototype/slice/S15.4.4.10_A3_T1.js    (no output)
built-ins/Array/prototype/slice/S15.4.4.10_A3_T2.js    (no output)
built-ins/Array/prototype/slice/S15.4.4.10_A4_T1.js    Uncaught exception: #3: Array.prototype[1] = 1; x = [0]; x.length = 2; var arr = x.slice()
built-ins/Array/prototype/slice/create-non-array-invalid-len.js    (no output)
built-ins/Array/prototype/slice/create-proxied-array-invalid-len.js    (no output)
built-ins/Array/prototype/toLocaleString/primitive_this_value.js    Uncaught exception: Expected SameValue(«"true,false"», «"boolean,boolean"») to be true
built-ins/Array/prototype/toLocaleString/primitive_this_value_getter.js    Uncaught exception: Expected SameValue(«"true,false"», «"boolean,boolean"») to be true
built-ins/Array/prototype/toString/S15.4.4.2_A3_T1.js    Uncaught exception: #1: Array.prototype[1] = 1; x = [0]; x.length = 2; x.toString() === "0
built-ins/Array/prototype/toString/call-with-boolean.js    Uncaught exception: Array.prototype.toString.call(true) must return "[object Boolean]" Exp
built-ins/Array/prototype/unshift/S15.4.4.13_A4_T1.js    Uncaught exception: #7: Object.prototype[0] = -1; Object.prototype.length = 1; Object.prot
built-ins/Array/prototype/unshift/S15.4.4.13_A4_T2.js    Uncaught exception: #3: Array.prototype[0] = 1; x = []; x.length = 1; x.unshift(0); x[1] =
built-ins/Array/prototype/unshift/set-length-array-is-frozen.js    Uncaught exception: Expected a TypeError to be thrown but no exception was thrown at all
built-ins/Array/prototype/unshift/set-length-array-length-is-non-writable.js    Uncaught exception: Expected a TypeError to be thrown but no exception was thrown at all
built-ins/Array/prototype/unshift/set-length-zero-array-is-frozen.js    Uncaught exception: Expected a TypeError to be thrown but no exception was thrown at all
built-ins/Array/prototype/unshift/set-length-zero-array-length-is-non-writable.js    Uncaught exception: Expected a TypeError to be thrown but no exception was thrown at all
built-ins/Array/prototype/values/iteration-mutable.js    Uncaught exception: Exhausted result `done` flag (after push) Expected SameValue(«false», 

Reproduce

scripts/test262_subset.py --root vendor/test262 --dir built-ins/Array --jobs 6

Each path is under vendor/test262/test/; assemble harness + case per test-compat/test262/README.md to run one under perry compile.