The mechanical half, riding on the census in the previous commit.
* 342 in-process construction sites in 65 files now take
`new_with_roots` / `open_with_roots` with `iso::roots()`. The isolated
base is a pure function of `CARGO_TARGET_TMPDIR` — no counter, no
`OnceLock` — so two copies of the module in one binary agree instead of
racing, and the tree lives somewhere `cargo clean` owns rather than
leaking into `/tmp` once per run. It is shared deliberately:
materialization is content-gated and idempotent, so a per-test
directory would repeat it ~330 times per run for a byte-identical
result.
* `journey_acceptance` keeps the ambient `EditorState::open`, because
proving the production entry point has a caller is the whole of what
that ratchet is for. Rev 2's "isolated by the environment its binary is
launched with" was not a mechanism — cargo launches each test binary
with the caller's environment, and a binary cannot re-point its own
roots before its tests run. Each test is now a thin parent that
re-execs this binary for its own name with controlled roots, and the
child runs the body against production's call. Two pins guard it: the
child asserts all four roots resolve inside the controlled base, and
the suite asserts against its own source that it has not quietly taken
the seam. The parent also asserts the child ran `1 passed` — a stale
`--exact` filter would otherwise hollow the whole thing out silently.
* The shared spawners take all five storage variables.
`spawn_daemon_process_with_env` set `HOME` and `XDG_CONFIG_HOME` only;
`HOME` is a FALLBACK, so it isolates a root only while the matching
`XDG_*` is unset — the harness's apparent adequacy was a property of
one developer's environment. The PTY spawner backfills whichever of the
five its caller did not pin. The 10 direct `Command::new` daemon and
attach spawns get the same treatment.
Three suites had `mod common;` behind `#[cfg(feature = "crdt")]`;
`common::iso` is needed in every build, so those are ungated. Files that
already pull in `common` reach `iso` through a `use` rather than a second
`#[path]` declaration — loading one file as two modules is
`clippy::duplicate_mod`.
Co-Authored-By: Claude Opus 5 <noreply@anthropic.com>
Claude-Session: https://claude.ai/code/session_01Lv428Fth9LRtffwJSsqH7T