test(authoring): use physical roots for mutation fixtures

cli/plugin-kit-ai/internal/authoring/commands/public_contract_test.go

@@ -342,7 +342,7 @@ func TestPublicLiteralExamplesAndEveryLeaf(t *testing.T) {
 			var first [][]byte
 			var firstTree map[string]string
 			for _, mount := range []bool{false, true} {
-				parent := t.TempDir()
+				parent := physicalMutationRoot(t)
 				t.Chdir(parent)
 				a := publicApp(t)
 				args := append([]string{"init", lane.name, "--format=json"}, lane.flags...)
@@ -408,7 +408,7 @@ func TestPublicLiteralExamplesAndEveryLeaf(t *testing.T) {
 }
 
 func TestPublicCWDAndExplicitInputs(t *testing.T) {
-	parent := t.TempDir()
+	parent := physicalMutationRoot(t)
 	t.Chdir(parent)
 	a := publicApp(t)
 	root := filepath.Join(parent, "explicit-destination")
@@ -681,7 +681,7 @@ func TestPublicAnnotatedErrorAndRealCleanup(t *testing.T) {
 	noPolicy(t, e)
 	for _, canceled := range []bool{false, true} {
 		for _, mount := range []bool{false, true} {
-			parent := t.TempDir()
+			parent := physicalMutationRoot(t)
 			ctx, cancel := context.WithCancel(context.Background())
 			stage := ""
 			fault := faultContext{Context: ctx, check: func() {

cli/plugin-kit-ai/internal/authoring/commands/skills_test.go

@@ -17,9 +17,20 @@ import (
 	"github.com/777genius/plugin-kit-ai/install/integrationctl/agentplugins/conformance"
 )
 
+// physicalMutationRoot resolves only a fresh owned infrastructure directory,
+// before fixture inputs (including deliberate symlinks) are constructed.
+func physicalMutationRoot(t *testing.T) string {
+	t.Helper()
+	root, err := filepath.EvalSymlinks(t.TempDir())
+	if err != nil {
+		t.Fatal(err)
+	}
+	return root
+}
+
 func TestSkillsFactoriesAndEntrypointParity(t *testing.T) {
 	a := commands.App{Projects: project.Service{Scratch: t.TempDir()}, Revision: "skills-factories"}
-	roots := []string{t.TempDir(), t.TempDir()}
+	roots := []string{physicalMutationRoot(t), physicalMutationRoot(t)}
 	for _, root := range roots {
 		write(t, root, "plugin.json", plugin(""))
 		write(t, root, "keep", marker)
@@ -105,7 +116,7 @@ func TestSkillsFactoriesAndEntrypointParity(t *testing.T) {
 	}
 }
 func TestSkillsExactCWD(t *testing.T) {
-	root := t.TempDir()
+	root := physicalMutationRoot(t)
 	write(t, root, "plugin.json", plugin(""))
 	child := filepath.Join(root, "child")
 	if e := os.Mkdir(child, 0700); e != nil {
@@ -160,7 +171,7 @@ func TestSkillsHumanAllowlist(t *testing.T) {
 func TestSkillsPostCommitErrorIsExplicit(t *testing.T) {
 	for _, mount := range []bool{false, true} {
 		for _, jsonOutput := range []bool{false, true} {
-			root := t.TempDir()
+			root := physicalMutationRoot(t)
 			write(t, root, "plugin.json", plugin(""))
 			a := commands.App{Projects: project.Service{Scratch: t.TempDir(), Limits: packageview.Limits{Entries: 1}}}
 			args := []string{"skills", "init", "new", "--description", "text", root}

cli/plugin-kit-ai/internal/authoring/commands/vertical_fix_test.go

@@ -104,7 +104,7 @@ func TestReviewInitCleanupFailurePrecedence(t *testing.T) {
 				boundary = "command"
 			}
 			t.Run(fixture+"/"+boundary, func(t *testing.T) {
-				parent, scratch := t.TempDir(), t.TempDir()
+				parent, scratch := physicalMutationRoot(t), t.TempDir()
 				ctx, cancel := context.WithCancel(context.Background())
 				defer cancel()
 				replaced := ""

cli/plugin-kit-ai/internal/authoring/scaffold/apply_test.go

@@ -107,7 +107,16 @@ func TestMissingParentSymlinkParentAndSourceOverlap(t *testing.T) {
 		t.Fatal(err)
 	}
 	p := planFor(t, "skill")
-	validate := realValidation(t)
+	validationCalls := 0
+	realValidate := realValidation(t)
+	validate := func(ctx context.Context, stage string, dir *os.Root) error {
+		validationCalls++
+		return realValidate(ctx, stage, dir)
+	}
+	// Prove this physical fixture reaches real validation before adding aliases.
+	if result, err := Apply(context.Background(), p, ApplyOptions{Destination: filepath.Join(root, "positive"), Validate: validate}); err != nil || !result.Committed || validationCalls != 1 {
+		t.Fatalf("physical root positive control: %+v %v calls=%d", result, err, validationCalls)
+	}
 	for _, o := range []ApplyOptions{
 		{Destination: filepath.Join(root, "missing", "out")},
 		{Destination: filepath.Join(source, "out"), SourceRoots: []string{source}},
@@ -133,6 +142,9 @@ func TestMissingParentSymlinkParentAndSourceOverlap(t *testing.T) {
 	if _, err := Apply(context.Background(), p, ApplyOptions{Destination: filepath.Join(source, "out"), SourceRoots: []string{alias}, Validate: validate}); err == nil {
 		t.Fatal("source alias overlap")
 	}
+	if validationCalls != 1 {
+		t.Fatalf("unsafe input reached validation: calls=%d", validationCalls)
+	}
 	assertOnly(t, source, "sentinel")
 	b, _ := os.ReadFile(filepath.Join(source, "sentinel"))
 	if string(b) != "untouched" {

cli/plugin-kit-ai/internal/authoring/scaffold/skill_plan_test.go

@@ -21,7 +21,7 @@ import (
 
 func skillFixture(t *testing.T) (string, SkillPlan, SkillSourceGate) {
 	t.Helper()
-	root, scratch := t.TempDir(), t.TempDir()
+	root, scratch := tempRoot(t), t.TempDir()
 	body := []byte(`{"$schema":"` + domain.PluginSchemaV1 + `","name":"fixture"}`)
 	if e := os.WriteFile(filepath.Join(root, "plugin.json"), body, 0600); e != nil {
 		t.Fatal(e)
@@ -135,7 +135,9 @@ func TestSkillAtomicFailureAndStagedValidation(t *testing.T) {
 			ctx, cancel := context.WithCancel(context.Background())
 			defer cancel()
 			injected := errors.New("injected I/O failure")
+			writeReached := false
 			ops := applyOps{write: func(ctx context.Context, r *os.Root, files []File) error {
+				writeReached = true
 				if mode == "write-failure" {
 					if e := r.Mkdir("partial", 0700); e != nil {
 						return e
@@ -189,6 +191,9 @@ func TestSkillAtomicFailureAndStagedValidation(t *testing.T) {
 				return nil
 			}}
 			r, e := applySkill(ctx, p, root, gate, sharedSkillValidation("new-skill"), ops)
+			if !writeReached {
+				t.Fatalf("write fault callback not reached: %v", e)
+			}
 			if e == nil {
 				t.Fatal("injected failure reported success")
 			}

cli/plugin-kit-ai/internal/authoring/skills/skills_test.go

@@ -31,9 +31,21 @@ func put(t *testing.T, root, path, body string) {
 		t.Fatal(err)
 	}
 }
+
+// physicalMutationRoot resolves only a fresh owned infrastructure directory,
+// before fixture inputs (including deliberate symlinks) are constructed.
+func physicalMutationRoot(t *testing.T) string {
+	t.Helper()
+	root, err := filepath.EvalSymlinks(t.TempDir())
+	if err != nil {
+		t.Fatal(err)
+	}
+	return root
+}
+
 func setup(t *testing.T) (skills.Service, string) {
 	t.Helper()
-	root := t.TempDir()
+	root := physicalMutationRoot(t)
 	put(t, root, "plugin.json", `{"$schema":"`+domain.PluginSchemaV1+`","name":"fixture"}`)
 	return skills.Service{Projects: project.Service{Scratch: t.TempDir()}, Revision: "skills-test"}, root
 }
@@ -212,7 +224,7 @@ func TestSkillContainmentAndSourceGate(t *testing.T) {
 			selected := root
 			switch kind {
 			case "root-link":
-				selected = filepath.Join(t.TempDir(), "link")
+				selected = filepath.Join(physicalMutationRoot(t), "link")
 				if e := os.Symlink(root, selected); e != nil {
 					t.Fatal(e)
 				}