L-sized improvement #10 (cookbook scratch-rebuild) is now
PARTIALLY shipped: the M-sized foundation is a runnable
script that does the right thing in the common case.
Verification against real cascades + integration with
rebuild-cascade.sh remains for a separate session.
local/scripts/scratch-rebuild.sh (190 lines, +x):
Step 1: discover autotools-using recipes by content regex
(aclocal|autoreconf|libtoolize|automake|autoconf|gettextize|./configure)
PLUS the AUTOTOOLS_CORE list (m4, autoconf, automake,
libtool, bison, flex, gettext) which are always-included
because they are autotools infrastructure even if they
don't directly invoke aclocal.
Step 2: compute transitive closure via BFS over the recipe
TOML dep graph, including both [build].dependencies and
[build].dev_dependencies. Found 6 autotools users in the
live tree: bison, diffutils, flex, grub, libtool, m4.
Step 3: for each recipe in the closure, delete
target/<arch>/{build,sysroot,stage.tmp}/ — PRESERVE source/
so we don't re-fetch the upstream tar.
Step 4: re-cook in dep order with --jobs=N (default 4) so
the rebuild itself runs in parallel via the dep-aware
scheduler (#1).
Cook errors during Step 4 do NOT abort the script with
exit 1 — a failed cook may indicate a missing upstream dep
(legitimate on a fresh checkout) rather than a real bug.
The user inspects the log and re-runs after addressing the
dep. This is documented in the header + Step 4 comment.
Supports --dry-run, --jobs=N, --help. Env overrides for
RECIPES_DIR + LOG_DIR (mirroring the migration script's
test escape hatch pattern, used by the test suite below).
21 unit tests in local/scripts/tests/test_scratch_rebuild.py:
TestAutotoolsCoreList (3) — m4, libtool, bison/flex
in AUTOTOOLS_CORE
TestAutotoolsContentRegex (8) — catches each canonical
autotools command; does
NOT match cmake/make/meson
TestRecipeDepParsing (4) — parses dependencies and
dev_dependencies; both;
neither
TestScriptHelp (1) — --help describes the
script
TestScriptStructure (5) — executable bit; uses
./target/release/repo;
PRESERVES source/; uses
--jobs=N; dry-run safe
Test count: 99 -> 120 (all in <1s).
The test file also surfaces a real Python regex gotcha:
`^[[:space:]]*` (POSIX char class with quantifier) silently
fails to match the empty string under Python's regex
engine, while `^[\s]*` (shorthand) works correctly. The
test regex uses the shorthand to avoid this.
Wired into:
make test-scratch-dry-run -> scratch-rebuild.sh --dry-run
Gitea Actions job scratch-dry-run (job 6 of 10, every PR)
With this commit, 9 of 10 build-system improvements in
BUILD-SYSTEM-IMPROVEMENTS.md are DONE (1 PARTIAL on #10);
the remaining 1 is #7A (QML gate, Qt6 engine fix, not a
cookbook improvement).
Verified: `./local/scripts/scratch-rebuild.sh --dry-run`
correctly discovers 6 autotools users and computes the
6-recipe closure. `make test-lint-scripts` still passes
120/120 tests in <1s. Gitea workflow YAML validates with
10 jobs total (was 9).
kellito