Answers review of revision 17. Still framing only; no code.
**IDENTITY HAS A SECOND HALF, AND R2/R3 CANNOT REACH IT.** A panel or
terminal residual is keyed to a surface that GOES AWAY, so replacement
is naturally observable. The document's and the minimap's do not work
that way: they live in the long-lived GPU `State` and OUTLIVE the
buffer. Their reset is a manual list --- buffer replacement
(`pmacs-gpu/src/main.rs:5922` onward) zeroes `scroll_top`,
`code_scroll_residual` and `code_scroll_left` one explicit line at a
time, each with its own comment. A new wheel residual will not reset
itself, and nothing fails if it is forgotten except a user's next
document scrolling from someone else's offset.
R4 document A -> document B, covering the document residual AND the
chrome residual it shares; successor starts from zero.
Mutation: omit the document residual from the replacement reset.
R5 minimap across A -> B; its residual is independent (B6) so it
needs its own reset and its own leg.
Mutation: omit the minimap residual from the replacement reset.
The mutations are deliberately separate --- one reset omitted at a time
--- because a single "forgot to reset" mutation would bite both legs
and prove neither field individually covered. `code_scroll_left` had
precisely this defect once, which is why it now carries a comment
explaining that a switch would otherwise inherit the previous
document's leftward viewport.
**AND TWO OVERCLAIMS IN THE SIGNATURE ROWS.** I wrote that both steps
ran "the same executable". They ran the same TARGET but different
ARTIFACTS: `pmacs-9d4963151c6f3151` at 211,777,472 bytes and
`pmacs-7624ed4bed0b6617` at 214,462,056, and `cmp` reports differing
bytes. What is supported is the same libtest target, its 1,940-test
population, and default intra-binary threading --- which is all the
concurrency conclusion ever needed, so that conclusion is unchanged.
"Cargo runs test binaries sequentially" was also stated as a universal.
It is narrowed to what was observed: under cargo 1.95.0, this sweep ran
its 119 binaries sequentially. The rows no longer generalize to cargo
versions or invocations they did not measure.
Gates: all nine green under `env -u TMPDIR`, log 20260814T110707Z.
Co-Authored-By: Claude Opus 5 <noreply@anthropic.com>
Claude-Session: https://claude.ai/code/session_016bqGA6s9tTUFzYpbeW3tai
Levi Neuwirth
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