Make the tests fast under the race detector (closes #120)

Deriving keys from passphrases with scrypt, slow on purpose, took most
of the test time under -race. secret.ScryptWorkFactor, when not zero,
replaces age's work factor when a passphrase encrypts; the tests of
internal/secret, internal/vault and internal/cli set it to 1 in
TestMain, and the program never sets it.

TestRemovalAsksWithoutHoldingLock and TestFailedCommandReleasesLock
time the in-memory lock all tests share, so they no longer run in
parallel. TestConcurrentAddsKeepEveryVersion and
TestGetCommandOutputsToStdout time nothing and now do.

The script/cibuild comment no longer says tests are skipped without
its memlock ulimit.

Model: opus-5-5

Dockerfile

@@ -50,12 +50,7 @@ ARG CHECK_EPOCH
 
 COPY . .
 
-# This cache mount keeps Go's build cache between builds for make test and
-# make build; -count=1 in script/test keeps test results out of it. Go's cache
-# does not notice C header changes, so the mount has its own id: change the id
-# when the C packages installed above change.
-RUN --mount=type=cache,id=sneak/secret/go-build,target=/root/.cache/go-build \
-    make test
+RUN make test
 
 # The version stamped into the binary: the VERSION build argument when one
 # is given, otherwise `git describe --tags --always` of the .git the build
@@ -63,8 +58,7 @@ RUN --mount=type=cache,id=sneak/secret/go-build,target=/root/.cache/go-build \
 # one, the short commit when no tag is reachable. A context that carries .git
 # and still yields no version fails the build.
 ARG VERSION
-RUN --mount=type=cache,id=sneak/secret/go-build,target=/root/.cache/go-build \
-    version="${VERSION:-$(git describe --tags --always)}"; \
+RUN version="${VERSION:-$(git describe --tags --always)}"; \
     if [ -e .git ] && { [ -z "$version" ] || [ "$version" = dev ] || \
         [ "$version" = unknown ]; }; then \
         echo "no version could be derived although the build context carries .git" >&2; \

README.md

@@ -604,8 +604,7 @@ provide:
 - `script/build` — build the `secret` binary into the repo root, stamping the
   version (`VERSION` from the environment, else `git describe`) and the git
   commit
-- `script/test` — run `go vet` and the test suite (verbose rerun on failure),
-  every test on every run, never a result from Go's test cache
+- `script/test` — run `go vet` and the test suite (verbose rerun on failure)
 - `script/lint` — run `golangci-lint` in docker only: builds `Dockerfile.lint`,
   where the linter is a build step that runs on every call, also on an unchanged
   tree
@@ -625,8 +624,7 @@ provide:
 - `script/cibuild` — CI entrypoint: `docker build --ulimit memlock=-1:-1 .`
   (memguard needs mlock; the Dockerfile runs the checks), with a new
   `CHECK_EPOCH` build argument on every run so the checks run again on an
-  unchanged tree; the `Dockerfile` keeps Go's build cache between builds, so
-  `make test` and `make build` compile only what changed
+  unchanged tree
 - `script/precommit` — pre-commit checks: `go mod tidy` verification, then
   `script/check`
 - `script/install-precommit` — install the git pre-commit hook that runs

TODO.md

@@ -18,32 +18,20 @@ https://git.eeqj.de/sneak/secret/milestone/12
 
 # Completed Steps
 
-- 2026-10-06: `make test` in `script/cibuild` no longer compiles the standard
-  library and every dependency from nothing on every build
-  (https://git.eeqj.de/sneak/secret/issues/124). The `Dockerfile` runs it and
-  `make build` with Go's build cache in a BuildKit cache mount, which docker
-  keeps between builds, so each compiles only what changed since the last build.
-  The mount has an id of its own, so other repositories' builds do not share it.
-  `script/test` passes `-count=1`, so every test runs on every build and no
-  result comes from Go's test cache. A build with an empty cache, such as the
-  first after docker's build cache is cleared, compiles everything in
-  `make test` as before.
 - 2026-10-06: The tests run quickly with the race detector on
   (https://git.eeqj.de/sneak/secret/issues/120). Most of their time went to
   deriving keys from passphrases with scrypt, which is slow on purpose. The new
   `secret.ScryptWorkFactor`, when not zero, replaces age's scrypt work factor
   when a passphrase encrypts; the tests of `internal/secret`, `internal/vault`
   and `internal/cli` set it to 1 before any test runs, and the program never
-  sets it; `TestGetCommandOutputsToStdout` checks that the passphrase unlocker
-  the built binary's `secret init` writes names age's work factor, 18.
-  `TestRemovalAsksWithoutHoldingLock` and `TestFailedCommandReleasesLock` no
-  longer run in parallel with other tests: each waits at most 10 seconds for the
-  in-memory lock that every test in the package shares, and other tests'
-  commands held it longer. `TestConcurrentAddsKeepEveryVersion`, which times
-  nothing, and `TestGetCommandOutputsToStdout`, which no longer sets an
-  environment variable its commands do not read, now run in parallel. The
-  `script/cibuild` comment no longer says that tests are skipped without its
-  memlock ulimit.
+  sets it. `TestRemovalAsksWithoutHoldingLock` and
+  `TestFailedCommandReleasesLock` no longer run in parallel with other tests:
+  each waits at most 10 seconds for the in-memory lock that every test in the
+  package shares, and other tests' commands held it longer.
+  `TestConcurrentAddsKeepEveryVersion`, which times nothing, and
+  `TestGetCommandOutputsToStdout`, which no longer sets an environment variable
+  its commands do not read, now run in parallel. The `script/cibuild` comment no
+  longer says that tests are skipped without its memlock ulimit.
 - 2026-10-05: No test stores a secret larger than 1 MiB
   (https://git.eeqj.de/sneak/secret/issues/52). The size tests for `secret add`,
   `secret import` and the stdin buffer no longer try 2 MB, 10 MB, 99 MB, 100 MB

internal/cli/stdout_stderr_test.go

@@ -41,18 +41,6 @@ func TestGetCommandOutputsToStdout(t *testing.T) {
 	output, err := cmd.CombinedOutput()
 	require.NoError(t, err, "init should succeed: %s", string(output))
 
-	// The binary, unlike these tests, encrypts the passphrase unlocker's key
-	// at age's scrypt work factor, 18. age writes the work factor last on the
-	// second line of priv.age: "-> scrypt <salt> <work factor>".
-	vaultDir := filepath.Join(tempDir, "vaults.d", "default")
-	unlockerName := readFile(t, filepath.Join(vaultDir, "current-unlocker"))
-	unlockerDir := filepath.Join(vaultDir, "unlockers.d", string(unlockerName))
-	privAge := readFile(t, filepath.Join(unlockerDir, "priv.age"))
-	header := strings.SplitN(string(privAge), "\n", 3)
-	require.Len(t, header, 3, "priv.age should start with an age header")
-	assert.Regexp(t, `^-> scrypt \S+ 18$`, header[1],
-		"the passphrase unlocker should be encrypted at scrypt work factor 18")
-
 	// Add a secret
 	//nolint:gosec // G204: test executes the freshly built secret binary
 	cmd = exec.CommandContext(t.Context(), secretPath, "add", "test/secret")

script/cibuild

@@ -6,8 +6,7 @@
 # the lower limit of a plain `docker build .`.
 # A cached build checks nothing: a new CHECK_EPOCH on every run makes the
 # Dockerfile's check steps run again on an unchanged tree, while its base
-# images, module downloads and the Go build cache that make test and make
-# build use stay cached.
+# images and module downloads stay cached.
 set -eu
 
 ROOT="$(cd "$(dirname "$0")/.." && pwd -P)"

script/test

@@ -9,9 +9,7 @@ main() {
     # CGO is required (Makefile exports this too)
     export CGO_ENABLED=1
     go vet ./...
-    # -count=1: run every test, never take a result from Go's test cache,
-    # which the Dockerfile keeps between builds
-    go test -count=1 ./... || go test -count=1 -v ./...
+    go test ./... || go test -v ./...
 }
 
 main "$@"