feat: add deployment foundation and cross-device handoff

internal/planner/plan_test.go

@@ -0,0 +1,71 @@
+package planner
+
+import (
+	"testing"
+	"time"
+)
+
+func TestBuildPlan(t *testing.T) {
+	now := time.Date(2026, 9, 25, 12, 0, 0, 0, time.UTC)
+	i := validIntent()
+	p, err := Build(i, now)
+	if err != nil {
+		t.Fatal(err)
+	}
+	if p.ProjectName != "sd-git-one" || p.DataPath != "/var/lib/server-deploy/instances/git-one" {
+		t.Fatalf("wrong instance resources: %+v", p)
+	}
+	if p.ExpiresAt.Sub(p.CreatedAt) != 15*time.Minute {
+		t.Fatal("wrong expiration")
+	}
+	if err := p.Verify(i, now); err != nil {
+		t.Fatal(err)
+	}
+	again, _ := Build(i, now)
+	if again.Hash != p.Hash {
+		t.Fatal("unstable plan hash")
+	}
+	i.InstanceID = "git-two"
+	other, _ := Build(i, now)
+	if other.Hash == p.Hash || other.ProjectName == p.ProjectName || other.DataPath == p.DataPath {
+		t.Fatal("instances share identity")
+	}
+}
+
+func TestVerifyRejectsChangedOrExpiredPlan(t *testing.T) {
+	now := time.Date(2026, 9, 25, 12, 0, 0, 0, time.UTC)
+	i := validIntent()
+	original, _ := Build(i, now)
+	cases := []struct {
+		name   string
+		change func(*Plan, *Intent, *time.Time)
+	}{
+		{"expired", func(p *Plan, i *Intent, n *time.Time) { *n = p.ExpiresAt }},
+		{"future", func(p *Plan, i *Intent, n *time.Time) { *n = p.CreatedAt.Add(-time.Second) }},
+		{"tampered hash", func(p *Plan, i *Intent, n *time.Time) { p.Hash = "bad" }},
+		{"tampered path", func(p *Plan, i *Intent, n *time.Time) { p.DataPath = "/" }},
+		{"tampered project", func(p *Plan, i *Intent, n *time.Time) { p.ProjectName = "other" }},
+		{"tampered expiry", func(p *Plan, i *Intent, n *time.Time) { p.ExpiresAt = p.ExpiresAt.Add(time.Hour) }},
+		{"state drift", func(p *Plan, i *Intent, n *time.Time) { i.ObservedStateDigest = i.PackageDigest }},
+		{"host drift", func(p *Plan, i *Intent, n *time.Time) { i.HostID = "another-host" }},
+		{"domain drift", func(p *Plan, i *Intent, n *time.Time) { i.Domain = "other.example.com" }},
+		{"intent tamper", func(p *Plan, i *Intent, n *time.Time) { p.Intent.InstanceID = "other" }},
+	}
+	for _, tc := range cases {
+		t.Run(tc.name, func(t *testing.T) {
+			p, current, at := original, i, now
+			tc.change(&p, &current, &at)
+			if p.Verify(current, at) == nil {
+				t.Fatal("accepted invalid plan")
+			}
+		})
+	}
+}
+
+func TestBuildRejectsInvalidIntent(t *testing.T) {
+	i := validIntent()
+	i.InstanceID = "../bad"
+	if _, err := Build(i, time.Now()); err == nil {
+		t.Fatal("built invalid plan")
+	}
+}