Fix unbounded recursion on cyclic tables at the eval boundary - #2
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The standard Lua OOP idiom (T.__index = T) creates tables that contain
themselves. Both eval-boundary walks recursed into them forever,
growing memory without bound: Value.decode in decode: true mode and
Display.peek_table in decode: false mode.
The walk now terminates at the point of recurrence: decode leaves the
table's {:tref, id} reference there, mirroring how functions already
pass through as opaque references, and Display renders a :circular
peek. Shared non-cyclic references decode in full.
OTP 28's opacity checker false-positives on the MapSet the walkers capture in their entry closures (call_without_opaque on every MapSet call), failing CI. Specs on the private clauses don't appease it. A plain map with the ids as keys is the same structure MapSet wraps, so behavior is identical and there is no opaque type left to police.
fedme
approved these changes
Jul 27, 2026
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Mirror of tv-labs#407.
Bounds cyclic table walks at the eval boundary: Value.decode leaves the table's {:tref, id} reference in place, and Display renders a :circular peek. Also tracks the ancestor set as a plain map to satisfy OTP 28's opacity checker.
Upstream PR: tv-labs#407