Artifact [ac133766b5]

Artifact ac133766b5a1662f2cfb5381070cb40501e62e8824ac215c353c0ea0cd21aeea:

• File dst/simulator_test.go — part of check-in [6273a0750d] at 2026-07-22 23:03:24 on branch trunk — fix: correct go.mod module path to go-libfossil (#76) (#117)

  * fix: correct go.mod module path to go-libfossil (#76)

  The module directive still declared github.com/danmestas/libfossil after the repository was renamed to go-libfossil. pkg.go.dev/godoc scraping matches the declared module path against its hosting path, so the stale path broke SDK doc generation.

  Rename the module path across all four in-repo modules (root, the two db/driver submodules, observer/otel, and docs/site) and every internal import, plus the release workflow, the doc-generation script, and the docs.

  No tag has been published under the go-libfossil path yet, so the cross-module requires cannot resolve from the proxy. Add replace directives pointing the in-repo requires at their local directories so GOWORK=off builds and the CI matrix resolve without a published version. These replaces are ignored by downstream consumers and can be dropped once new-path tags are cut.

  * Guard releases against replace directives; regenerate SDK docs

  The go-libfossil rename bridges the in-repo modules with `replace` directives. Go refuses a main module that carries them, so a tag cut while they are present breaks `go install .../cmd/libfossil@<tag>` and every `@version` fetch of the driver submodules. Add a Release workflow step that fails the job before anything is published if any tracked go.mod still contains a replace directive, so the bridge is a CI-enforced TODO rather than a silent landmine. The step comment records what unblocks a release: re-tag the submodules with the corrected module paths, bump the root requires, then drop the replace blocks.

  Regenerate the SDK reference docs. The previous pass only substituted URLs over the pre-existing generated files, leaving stale signatures (Repo.Timeline was still documented as taking LogOpts rather than TimelineOpts). Note that gomarkdoc must be run outside a git worktree — inside one it silently strips every source link.

  Also reword the README rename note, which read as though the import path had not changed, and re-sort the ncruces require block. (user: [email protected], size: 7365) [annotate] [blame] [check-ins using]

package dst

import (
	"testing"
	"time"

	libsync "github.com/danmestas/go-libfossil/internal/sync"
	"github.com/danmestas/go-libfossil/internal/xfer"
)

// echoUpstream returns an empty response (immediate convergence).
func echoUpstream() *libsync.MockTransport {
	return &libsync.MockTransport{
		Handler: func(req *xfer.Message) *xfer.Message {
			return &xfer.Message{}
		},
	}
}

func TestNewSimulator(t *testing.T) {
	sim, err := New(SimConfig{
		Seed:      42,
		NumLeaves: 3,
		TmpDir:    t.TempDir(),
		Upstream:  echoUpstream(),
	})
	if err != nil {
		t.Fatalf("New: %v", err)
	}
	defer sim.Close()

	if len(sim.LeafIDs()) != 3 {
		t.Fatalf("leaves = %d, want 3", len(sim.LeafIDs()))
	}
	for _, id := range sim.LeafIDs() {
		if sim.Leaf(id) == nil {
			t.Fatalf("Leaf(%s) = nil", id)
		}
		if sim.Leaf(id).Repo() == nil {
			t.Fatalf("Leaf(%s).Repo() = nil", id)
		}
	}
}

func TestSimulatorSingleStep(t *testing.T) {
	sim, err := New(SimConfig{
		Seed:         1,
		NumLeaves:    1,
		PollInterval: 5 * time.Second,
		TmpDir:       t.TempDir(),
		Upstream:     echoUpstream(),
	})
	if err != nil {
		t.Fatalf("New: %v", err)
	}
	defer sim.Close()

	more, err := sim.Step()
	if err != nil {
		t.Fatalf("Step: %v", err)
	}
	if !more {
		t.Fatal("expected more events")
	}
	if sim.Steps != 1 {
		t.Fatalf("Steps = %d, want 1", sim.Steps)
	}
	if sim.TotalSyncs != 1 {
		t.Fatalf("TotalSyncs = %d, want 1", sim.TotalSyncs)
	}
}

func TestSimulatorRun(t *testing.T) {
	sim, err := New(SimConfig{
		Seed:         99,
		NumLeaves:    2,
		PollInterval: 5 * time.Second,
		TmpDir:       t.TempDir(),
		Upstream:     echoUpstream(),
	})
	if err != nil {
		t.Fatalf("New: %v", err)
	}
	defer sim.Close()

	if err := sim.Run(10); err != nil {
		t.Fatalf("Run: %v", err)
	}

	if sim.Steps != 10 {
		t.Fatalf("Steps = %d, want 10", sim.Steps)
	}
	if sim.TotalSyncs != 10 {
		t.Fatalf("TotalSyncs = %d, want 10", sim.TotalSyncs)
	}
	if sim.TotalErrors != 0 {
		t.Fatalf("TotalErrors = %d, want 0", sim.TotalErrors)
	}
}

func TestSimulatorRunUntil(t *testing.T) {
	sim, err := New(SimConfig{
		Seed:         7,
		NumLeaves:    2,
		PollInterval: 5 * time.Second,
		TmpDir:       t.TempDir(),
		Upstream:     echoUpstream(),
	})
	if err != nil {
		t.Fatalf("New: %v", err)
	}
	defer sim.Close()

	// Run for 30 virtual seconds. With 2 leaves at 5s intervals
	// (staggered start), expect ~12 sync events.
	deadline := sim.Clock().Now().Add(30 * time.Second)
	if err := sim.RunUntil(deadline); err != nil {
		t.Fatalf("RunUntil: %v", err)
	}

	if sim.TotalSyncs < 10 {
		t.Fatalf("TotalSyncs = %d, expected >= 10", sim.TotalSyncs)
	}
	// Clock should be at or past the deadline.
	if sim.Clock().Now().Before(deadline) {
		t.Fatalf("clock = %v, expected >= %v", sim.Clock().Now(), deadline)
	}
}

func TestSimulatorScheduleSyncNow(t *testing.T) {
	sim, err := New(SimConfig{
		Seed:         123,
		NumLeaves:    1,
		PollInterval: 1 * time.Hour, // very long — timer won't fire
		TmpDir:       t.TempDir(),
		Upstream:     echoUpstream(),
	})
	if err != nil {
		t.Fatalf("New: %v", err)
	}
	defer sim.Close()

	leafID := sim.LeafIDs()[0]

	// The initial timer event is scheduled at some random offset < 1h.
	// Inject a SyncNow at time zero — it should be processed first.
	sim.ScheduleSyncNow(leafID)

	more, err := sim.Step()
	if err != nil {
		t.Fatalf("Step: %v", err)
	}
	if !more {
		t.Fatal("expected more events")
	}
	if sim.TotalSyncs != 1 {
		t.Fatalf("TotalSyncs = %d, want 1", sim.TotalSyncs)
	}
	// Clock should still be at zero (SyncNow was at time 0).
	if !sim.Clock().Now().Equal(time.Unix(0, 0)) {
		t.Fatalf("clock = %v, expected epoch", sim.Clock().Now())
	}
}

func TestSimulatorNetworkPartition(t *testing.T) {
	sim, err := New(SimConfig{
		Seed:         55,
		NumLeaves:    1,
		PollInterval: 5 * time.Second,
		TmpDir:       t.TempDir(),
		Upstream:     echoUpstream(),
	})
	if err != nil {
		t.Fatalf("New: %v", err)
	}
	defer sim.Close()

	leafID := sim.LeafIDs()[0]

	// Partition the leaf.
	sim.Network().Partition(leafID)

	// Run one step — sync should fail due to partition.
	sim.Step()
	if sim.TotalErrors != 1 {
		t.Fatalf("TotalErrors = %d, want 1 (partitioned)", sim.TotalErrors)
	}

	// Heal and run another step — should succeed.
	sim.Network().Heal(leafID)
	sim.Step()
	if sim.TotalSyncs != 2 {
		t.Fatalf("TotalSyncs = %d, want 2", sim.TotalSyncs)
	}
	if sim.TotalErrors != 1 {
		t.Fatalf("TotalErrors = %d, want 1 (only the partitioned one)", sim.TotalErrors)
	}
}

func TestSimulatorDropRate(t *testing.T) {
	sim, err := New(SimConfig{
		Seed:         77,
		NumLeaves:    1,
		PollInterval: 1 * time.Second,
		TmpDir:       t.TempDir(),
		Upstream:     echoUpstream(),
	})
	if err != nil {
		t.Fatalf("New: %v", err)
	}
	defer sim.Close()

	// Set 100% drop rate — all syncs should fail.
	sim.Network().SetDropRate(1.0)

	if err := sim.Run(5); err != nil {
		t.Fatalf("Run: %v", err)
	}

	if sim.TotalErrors != 5 {
		t.Fatalf("TotalErrors = %d, want 5 (all dropped)", sim.TotalErrors)
	}
}

func TestSimulatorBuggify(t *testing.T) {
	sim, err := New(SimConfig{
		Seed:         42,
		NumLeaves:    2,
		PollInterval: 1 * time.Second,
		TmpDir:       t.TempDir(),
		Upstream:     echoUpstream(),
		Buggify:      true,
	})
	if err != nil {
		t.Fatalf("New: %v", err)
	}
	defer sim.Close()

	// Run many steps — buggify should cause some errors or skipped syncs.
	sim.Run(200)

	t.Logf("Buggify run: %d steps, %d syncs, %d errors",
		sim.Steps, sim.TotalSyncs, sim.TotalErrors)

	// With buggify enabled:
	// - Node Tick may skip syncs (5% on timer events) → TotalSyncs < Steps
	// - Storage buggify (3%) may cause sync errors → TotalErrors > 0
	// We can't assert exact numbers (depends on seed), but log them.
	if sim.TotalSyncs == sim.Steps {
		t.Logf("NOTE: no syncs were skipped by buggify (seed-dependent)")
	}
}

func TestSimulatorBuggifyDeterministic(t *testing.T) {
	run := func(seed int64) (int, int) {
		sim, err := New(SimConfig{
			Seed:         seed,
			NumLeaves:    2,
			PollInterval: 1 * time.Second,
			TmpDir:       t.TempDir(),
			Upstream:     echoUpstream(),
			Buggify:      true,
		})
		if err != nil {
			t.Fatalf("New: %v", err)
		}
		defer sim.Close()
		sim.Run(100)
		return sim.TotalSyncs, sim.TotalErrors
	}

	syncs1, errors1 := run(77)
	syncs2, errors2 := run(77)
	if syncs1 != syncs2 || errors1 != errors2 {
		t.Fatalf("buggify non-deterministic: run1=(%d,%d) run2=(%d,%d)",
			syncs1, errors1, syncs2, errors2)
	}
}

func TestSimulatorDeterministic(t *testing.T) {
	run := func(seed int64) (int, int) {
		sim, err := New(SimConfig{
			Seed:         seed,
			NumLeaves:    3,
			PollInterval: 5 * time.Second,
			TmpDir:       t.TempDir(),
			Upstream:     echoUpstream(),
		})
		if err != nil {
			t.Fatalf("New: %v", err)
		}
		defer sim.Close()

		sim.Network().SetDropRate(0.3) // 30% drops
		sim.Run(50)
		return sim.TotalSyncs, sim.TotalErrors
	}

	syncs1, errors1 := run(42)
	syncs2, errors2 := run(42)

	if syncs1 != syncs2 || errors1 != errors2 {
		t.Fatalf("non-deterministic: run1=(%d,%d) run2=(%d,%d)",
			syncs1, errors1, syncs2, errors2)
	}

	// Different seed should (very likely) produce different results.
	syncs3, errors3 := run(999)
	if syncs1 == syncs3 && errors1 == errors3 {
		t.Logf("WARNING: different seeds produced same result (unlikely but possible)")
	}
}