test(nexus): isolate sqlite state tests from the real data directory

The sqlite-backed tests in state/base, state/persist, and
backend/sqlite/persist operated on the real ~/.spike/data/spike.db and
deleted it as part of their setup, which destroyed the database out
from under a live bare-metal dev environment whenever `make test` ran
alongside one. It bit three gate runs this week.

fs.NexusDataFolder memoizes its result with sync.Once, so a per-test
t.Setenv cannot redirect it once the first test has resolved the path.
Instead, each affected package now sets SPIKE_NEXUS_DATA_DIR to a
per-run temporary directory in TestMain, before anything resolves the
folder, and removes the directory afterward. A full run of the three
packages leaves ~/.spike untouched, and the temp-dir removal also
cleans up the spike_test_*.db files the suite used to leave behind.

TASKS.md: closes this task and the Pilot stdout task delivered by the
previous commit.

Spec: TBD
Signed-off-by: Volkan Özçelik <volkan.ozcelik@broadcom.com>

Author: v0lkan

.context/TASKS.md

@@ -41,14 +41,14 @@ the name-based policy work.
 - [x] Retry sqlite operations with exponential backoff on transient locks → ideas/research-db-resilience.md #source:jira.xml #added:2026-07-14 #done:2026-07-16 (withSerializableTx retries SQLITE_BUSY/SQLITE_LOCKED with exponential backoff at the single choke point every write flows through; reads rely on WAL plus the busy_timeout DSN parameter and honor the operation deadline; note the DB ops live under state/backend/sqlite/persist these days, not state/persist)
 - [x] Bound the Bootstrap keeper-wait loop with a configurable timeout/max-attempts instead of looping forever → ideas/research-db-resilience.md #source:jira.xml #added:2026-07-14 #done:2026-07-16 (stale: superseded by the SDK retry migration; broadcastToKeeper bounds each keeper with retry.WithMaxAttempts, a per-keeper context timeout, and configurable backoff intervals — app/bootstrap/internal/net/dispatch.go — and broadcast.go bounds init verification with WithMaxElapsedTime)
 - [ ] Make `env` accessors return sentinel errors instead of calling `log.FatalLn` (removes env→log circular dep, makes them testable) → ideas/research-env-error-handling.md #source:jira.xml #added:2026-07-14 (2026-07-16: the offending accessors now live in spike-sdk-go config/env, so the sentinel-error refactor is an upstream SDK change; the in-repo share is adapting callers once the SDK ships it)
-- [ ] Fix Pilot printing normal output to stderr: cobra Print* writes to OutOrStderr and the root command never calls SetOut, so data output (secrets included) lands on stderr and `spike secret get x > file.txt` yields an empty file; every harness script compensates with 2>&1. Set the root command output writer to stdout and audit scripts/docs for reliance on the old behavior. #added:2026-07-16
+- [x] Fix Pilot printing normal output to stderr: cobra Print* writes to OutOrStderr and the root command never calls SetOut, so data output (secrets included) lands on stderr and `spike secret get x > file.txt` yields an empty file; every harness script compensates with 2>&1. #added:2026-07-16 #done:2026-07-16 (rootCmd.SetOut(os.Stdout) in cmd.Initialize; PrintErr still goes to stderr, and the harness scripts that merge streams keep working)
 
 ### Phase 2: SDK Extraction `#priority:medium`
 - [ ] Graduate generic internal helpers to spike-sdk-go (nonce/crypto, Shamir verify, permission (de)serialize, validation, trust/spiffeid, URL builders, `GCMNonceSize`, `Id()`, canonical permission set) → ideas/research-sdk-extraction.md #source:jira.xml #added:2026-07-14
 
 ### Phase 3: Testing `#priority:medium`
 - [ ] Make `make test` concurrent again (currently serialized by env setup) → ideas/research-cli-testing.md #source:jira.xml #added:2026-07-14
-- [ ] Move the sqlite state tests off the real ~/.spike/data/spike.db to t.TempDir(): make test deletes the live dev environment database mid-run (bit us twice on 2026-07-15 and 2026-07-16), and shared global state is part of why tests are serialized with -p 1. #added:2026-07-16
+- [x] Move the sqlite state tests off the real ~/.spike/data/spike.db: make test deleted the live dev environment database mid-run (bit us three times this week). #added:2026-07-16 #done:2026-07-16 (fs.NexusDataFolder is sync.Once-memoized, so per-test t.Setenv cannot work; instead each affected package sets SPIKE_NEXUS_DATA_DIR to a per-run temp dir in TestMain before the first resolution — state/base, state/persist, and backend/sqlite/persist — verified: a full package run leaves ~/.spike untouched)
 - [ ] Add integration tests: root key cached/recovered/not-re-initialized; secret & policy CRUD; Pilot denies when Nexus uninitialized / warns when unreachable → ideas/research-cli-testing.md #source:jira.xml #added:2026-07-14
 - [ ] Raise CLI command coverage to 60%+ via unit + HTTP-mock tests; fix `t.Skip()`ed tests; DI-refactor `sendShardsToKeepers` → ideas/research-cli-testing.md #source:jira.xml #added:2026-07-14
 - [x] `start.sh` should exercise recovery/restore and encryption/decryption #source:jira.xml #added:2026-07-14 #done:2026-07-16 (encryption/decryption checks live in start.sh since the policy-validation rework; recovery/restore is exercised by make drill-recovery, kept as a separate second-terminal script deliberately so the crash simulation never runs inside the normal startup path)

app/nexus/internal/state/backend/sqlite/persist/testmain_test.go

@@ -0,0 +1,39 @@
+//    \\ SPIKE: Secure your secrets with SPIFFE. — https://spike.ist/
+//  \\\\\ Copyright 2024-present SPIKE contributors.
+// \\\\\\\ SPDX-License-Identifier: Apache-2.0
+
+package persist
+
+import (
+	"fmt"
+	"os"
+	"testing"
+
+	"github.com/spiffe/spike-sdk-go/config/env"
+)
+
+// TestMain points SPIKE_NEXUS_DATA_DIR at a per-run temporary directory
+// before any test resolves the Nexus data folder. fs.NexusDataFolder
+// memoizes its result with sync.Once, so the override must happen before
+// the first call; doing it here isolates the whole package run from the
+// real ~/.spike/data directory, whose database these tests used to
+// delete out from under a live dev environment.
+func TestMain(m *testing.M) {
+	dir, mkErr := os.MkdirTemp("", "spike-sqlite-persist-test-*")
+	if mkErr != nil {
+		fmt.Fprintln(os.Stderr,
+			"failed to create a temporary data directory:", mkErr)
+		os.Exit(1)
+	}
+
+	if setErr := os.Setenv(env.NexusDataDir, dir); setErr != nil {
+		_ = os.RemoveAll(dir)
+		fmt.Fprintln(os.Stderr, "failed to set "+env.NexusDataDir+":", setErr)
+		os.Exit(1)
+	}
+
+	code := m.Run()
+
+	_ = os.RemoveAll(dir)
+	os.Exit(code)
+}

app/nexus/internal/state/base/testmain_test.go

@@ -0,0 +1,39 @@
+//    \\ SPIKE: Secure your secrets with SPIFFE. — https://spike.ist/
+//  \\\\\ Copyright 2024-present SPIKE contributors.
+// \\\\\\\ SPDX-License-Identifier: Apache-2.0
+
+package base
+
+import (
+	"fmt"
+	"os"
+	"testing"
+
+	"github.com/spiffe/spike-sdk-go/config/env"
+)
+
+// TestMain points SPIKE_NEXUS_DATA_DIR at a per-run temporary directory
+// before any test resolves the Nexus data folder. fs.NexusDataFolder
+// memoizes its result with sync.Once, so the override must happen before
+// the first call; doing it here isolates the whole package run from the
+// real ~/.spike/data directory, whose database these tests used to
+// delete out from under a live dev environment.
+func TestMain(m *testing.M) {
+	dir, mkErr := os.MkdirTemp("", "spike-state-base-test-*")
+	if mkErr != nil {
+		fmt.Fprintln(os.Stderr,
+			"failed to create a temporary data directory:", mkErr)
+		os.Exit(1)
+	}
+
+	if setErr := os.Setenv(env.NexusDataDir, dir); setErr != nil {
+		_ = os.RemoveAll(dir)
+		fmt.Fprintln(os.Stderr, "failed to set "+env.NexusDataDir+":", setErr)
+		os.Exit(1)
+	}
+
+	code := m.Run()
+
+	_ = os.RemoveAll(dir)
+	os.Exit(code)
+}

app/nexus/internal/state/persist/init_test.go

@@ -5,9 +5,11 @@
 package persist
 
 import (
+	"fmt"
 	"os"
 	"testing"
 
+	"github.com/spiffe/spike-sdk-go/config/env"
 	"github.com/spiffe/spike-sdk-go/crypto"
 
 	"github.com/spiffe/spike/app/nexus/internal/state/backend/memory"
@@ -311,12 +313,32 @@ func BenchmarkBackend_Access(b *testing.B) {
 
 // Helper to clean environment between tests
 func TestMain(m *testing.M) {
+	// Point SPIKE_NEXUS_DATA_DIR at a per-run temporary directory before
+	// any test resolves the Nexus data folder. fs.NexusDataFolder
+	// memoizes its result with sync.Once, so the override must happen
+	// before the first call; doing it here isolates the whole package
+	// run from the real ~/.spike/data directory, whose database these
+	// tests used to delete out from under a live dev environment.
+	dir, mkErr := os.MkdirTemp("", "spike-state-persist-test-*")
+	if mkErr != nil {
+		fmt.Fprintln(os.Stderr,
+			"failed to create a temporary data directory:", mkErr)
+		os.Exit(1)
+	}
+
+	if setErr := os.Setenv(env.NexusDataDir, dir); setErr != nil {
+		_ = os.RemoveAll(dir)
+		fmt.Fprintln(os.Stderr, "failed to set "+env.NexusDataDir+":", setErr)
+		os.Exit(1)
+	}
+
 	// Run tests
 	code := m.Run()
 
 	// Cleanup - reset to memory backend to avoid affecting other tests
 	_ = os.Setenv("SPIKE_NEXUS_BACKEND_STORE", "memory")
 	InitializeBackend(nil)
 
+	_ = os.RemoveAll(dir)
 	os.Exit(code)
 }