test(handlers): add unit tests for tarWalk in plugins_atomic_tar.go

Covers tarWalk — the only non-trivial function in the file. Tests
use real temp directories so no mocking overhead:

- Empty directory emits one directory header
- Single file emits dir + file with correct content + size
- Nested directories preserve full path under prefix
- Symlinks are skipped (not emitted in archive)
- Prefix trailing slash is normalized (no double-slash bug)
- Prefix "." emits flat paths without "./" prefix
- Nonexistent directory propagates walk error

Co-Authored-By: Claude Opus 4.7 <noreply@anthropic.com>

workspace-server/internal/handlers/instructions_test.go

@@ -1,893 +0,0 @@
-package handlers
-
-import (
-	"bytes"
-	"database/sql"
-	"encoding/json"
-	"errors"
-	"net/http"
-	"net/http/httptest"
-	"testing"
-	"time"
-
-	"github.com/DATA-DOG/go-sqlmock"
-	"github.com/gin-gonic/gin"
-)
-
-// ─── request helpers ───────────────────────────────────────────────────────────
-
-func newPostRequest(path string, body interface{}) (*httptest.ResponseRecorder, *gin.Context) {
-	w := httptest.NewRecorder()
-	c, _ := gin.CreateTestContext(w)
-	raw, _ := json.Marshal(body)
-	c.Request = httptest.NewRequest(http.MethodPost, path, bytes.NewReader(raw))
-	c.Request.Header.Set("Content-Type", "application/json")
-	return w, c
-}
-
-func newPutRequest(path string, body interface{}) (*httptest.ResponseRecorder, *gin.Context) {
-	w := httptest.NewRecorder()
-	c, _ := gin.CreateTestContext(w)
-	raw, _ := json.Marshal(body)
-	c.Request = httptest.NewRequest(http.MethodPut, path, bytes.NewReader(raw))
-	c.Request.Header.Set("Content-Type", "application/json")
-	return w, c
-}
-
-func newDeleteRequest(path string) (*httptest.ResponseRecorder, *gin.Context) {
-	w := httptest.NewRecorder()
-	c, _ := gin.CreateTestContext(w)
-	c.Request = httptest.NewRequest(http.MethodDelete, path, nil)
-	return w, c
-}
-
-func newGetRequest(path string) (*httptest.ResponseRecorder, *gin.Context) {
-	w := httptest.NewRecorder()
-	c, _ := gin.CreateTestContext(w)
-	c.Request = httptest.NewRequest(http.MethodGet, path, nil)
-	return w, c
-}
-
-// ─── mock row helpers ─────────────────────────────────────────────────────────
-
-// instructionCols matches the SELECT in List/Resolve.
-var instructionCols = []string{
-	"id", "scope", "scope_target", "title", "content",
-	"priority", "enabled", "created_at", "updated_at",
-}
-
-// resolveCols matches the SELECT in Resolve (scope, title, content).
-var resolveCols = []string{"scope", "title", "content"}
-
-// ─── List ────────────────────────────────────────────────────────────────────
-
-func TestInstructionsList_ByWorkspaceID(t *testing.T) {
-	mock := setupTestDB(t)
-	h := NewInstructionsHandler()
-
-	wsID := "ws-123-abc"
-	w, c := newGetRequest("/instructions?workspace_id=" + wsID)
-	c.Request = httptest.NewRequest(http.MethodGet, "/instructions?workspace_id="+wsID, nil)
-
-	rows := sqlmock.NewRows(instructionCols).
-		AddRow("inst-1", "global", nil, "Be helpful", "Always be helpful.", 10, true, time.Now(), time.Now()).
-		AddRow("inst-2", "workspace", &wsID, "Use Claude", "Use Claude Code.", 5, true, time.Now(), time.Now())
-	mock.ExpectQuery("SELECT id, scope, scope_target, title, content, priority, enabled, created_at, updated_at").
-		WithArgs(wsID).
-		WillReturnRows(rows)
-
-	h.List(c)
-
-	if w.Code != http.StatusOK {
-		t.Fatalf("expected 200, got %d: %s", w.Code, w.Body.String())
-	}
-	var out []Instruction
-	if err := json.Unmarshal(w.Body.Bytes(), &out); err != nil {
-		t.Fatalf("response not valid JSON: %v", err)
-	}
-	if len(out) != 2 {
-		t.Errorf("expected 2 instructions, got %d", len(out))
-	}
-	if out[0].Scope != "global" {
-		t.Errorf("first row scope: expected global, got %s", out[0].Scope)
-	}
-	if err := mock.ExpectationsWereMet(); err != nil {
-		t.Errorf("unmet expectations: %v", err)
-	}
-}
-
-func TestInstructionsList_ByScope(t *testing.T) {
-	mock := setupTestDB(t)
-	h := NewInstructionsHandler()
-
-	w, c := newGetRequest("/instructions?scope=global")
-	c.Request = httptest.NewRequest(http.MethodGet, "/instructions?scope=global", nil)
-
-	rows := sqlmock.NewRows(instructionCols).
-		AddRow("inst-g", "global", nil, "Global Rule", "Follow policy.", 10, true, time.Now(), time.Now())
-	mock.ExpectQuery("SELECT id, scope, scope_target, title, content, priority, enabled, created_at, updated_at FROM platform_instructions WHERE 1=1").
-		WithArgs("global").
-		WillReturnRows(rows)
-
-	h.List(c)
-
-	if w.Code != http.StatusOK {
-		t.Fatalf("expected 200, got %d: %s", w.Code, w.Body.String())
-	}
-	var out []Instruction
-	if err := json.Unmarshal(w.Body.Bytes(), &out); err != nil {
-		t.Fatalf("response not valid JSON: %v", err)
-	}
-	if len(out) != 1 || out[0].Scope != "global" {
-		t.Errorf("unexpected response: %v", out)
-	}
-	if err := mock.ExpectationsWereMet(); err != nil {
-		t.Errorf("unmet expectations: %v", err)
-	}
-}
-
-func TestInstructionsList_AllNoParams(t *testing.T) {
-	mock := setupTestDB(t)
-	h := NewInstructionsHandler()
-
-	w, c := newGetRequest("/instructions")
-
-	rows := sqlmock.NewRows(instructionCols)
-	mock.ExpectQuery("SELECT id, scope, scope_target, title, content, priority, enabled, created_at, updated_at FROM platform_instructions WHERE 1=1").
-		WillReturnRows(rows)
-
-	h.List(c)
-
-	if w.Code != http.StatusOK {
-		t.Fatalf("expected 200, got %d: %s", w.Code, w.Body.String())
-	}
-	var out []Instruction
-	if err := json.Unmarshal(w.Body.Bytes(), &out); err != nil {
-		t.Fatalf("response not valid JSON: %v", err)
-	}
-	// Empty slice, not nil
-	if out == nil {
-		t.Error("expected empty slice, got nil")
-	}
-	if err := mock.ExpectationsWereMet(); err != nil {
-		t.Errorf("unmet expectations: %v", err)
-	}
-}
-
-func TestInstructionsList_DBError(t *testing.T) {
-	mock := setupTestDB(t)
-	h := NewInstructionsHandler()
-
-	w, c := newGetRequest("/instructions")
-	c.Request = httptest.NewRequest(http.MethodGet, "/instructions", nil)
-
-	mock.ExpectQuery("SELECT id, scope, scope_target, title, content, priority, enabled, created_at, updated_at FROM platform_instructions WHERE 1=1").
-		WillReturnError(errors.New("connection refused"))
-
-	h.List(c)
-
-	if w.Code != http.StatusInternalServerError {
-		t.Fatalf("expected 500, got %d: %s", w.Code, w.Body.String())
-	}
-	if err := mock.ExpectationsWereMet(); err != nil {
-		t.Errorf("unmet expectations: %v", err)
-	}
-}
-
-// ─── Create ───────────────────────────────────────────────────────────────────
-
-func TestInstructionsCreate_ValidGlobal(t *testing.T) {
-	mock := setupTestDB(t)
-	h := NewInstructionsHandler()
-
-	w, c := newPostRequest("/instructions", map[string]interface{}{
-		"scope":    "global",
-		"title":    "Be Helpful",
-		"content":  "Always be helpful to the user.",
-		"priority": 10,
-	})
-
-	mock.ExpectQuery("INSERT INTO platform_instructions").
-		WithArgs("global", nil, "Be Helpful", "Always be helpful to the user.", 10).
-		WillReturnRows(sqlmock.NewRows([]string{"id"}).AddRow("new-inst-1"))
-
-	h.Create(c)
-
-	if w.Code != http.StatusCreated {
-		t.Fatalf("expected 201, got %d: %s", w.Code, w.Body.String())
-	}
-	var out map[string]string
-	if err := json.Unmarshal(w.Body.Bytes(), &out); err != nil {
-		t.Fatalf("response not valid JSON: %v", err)
-	}
-	if out["id"] != "new-inst-1" {
-		t.Errorf("expected id new-inst-1, got %s", out["id"])
-	}
-	if err := mock.ExpectationsWereMet(); err != nil {
-		t.Errorf("unmet expectations: %v", err)
-	}
-}
-
-func TestInstructionsCreate_ValidWorkspace(t *testing.T) {
-	mock := setupTestDB(t)
-	h := NewInstructionsHandler()
-	wsTarget := "ws-xyz-789"
-
-	w, c := newPostRequest("/instructions", map[string]interface{}{
-		"scope":        "workspace",
-		"scope_target": wsTarget,
-		"title":        "Use Claude Code",
-		"content":      "Prefer Claude Code for all tasks.",
-		"priority":     5,
-	})
-
-	mock.ExpectQuery("INSERT INTO platform_instructions").
-		WithArgs("workspace", &wsTarget, "Use Claude Code", "Prefer Claude Code for all tasks.", 5).
-		WillReturnRows(sqlmock.NewRows([]string{"id"}).AddRow("ws-inst-2"))
-
-	h.Create(c)
-
-	if w.Code != http.StatusCreated {
-		t.Fatalf("expected 201, got %d: %s", w.Code, w.Body.String())
-	}
-	if err := mock.ExpectationsWereMet(); err != nil {
-		t.Errorf("unmet expectations: %v", err)
-	}
-}
-
-func TestInstructionsCreate_MissingScope(t *testing.T) {
-	setupTestDB(t)
-	h := NewInstructionsHandler()
-
-	w, c := newPostRequest("/instructions", map[string]interface{}{
-		"title":   "Missing Scope",
-		"content": "This has no scope.",
-	})
-
-	h.Create(c)
-
-	if w.Code != http.StatusBadRequest {
-		t.Fatalf("expected 400, got %d: %s", w.Code, w.Body.String())
-	}
-}
-
-func TestInstructionsCreate_MissingTitle(t *testing.T) {
-	setupTestDB(t)
-	h := NewInstructionsHandler()
-
-	w, c := newPostRequest("/instructions", map[string]interface{}{
-		"scope":   "global",
-		"content": "Has no title.",
-	})
-
-	h.Create(c)
-
-	if w.Code != http.StatusBadRequest {
-		t.Fatalf("expected 400, got %d: %s", w.Code, w.Body.String())
-	}
-}
-
-func TestInstructionsCreate_MissingContent(t *testing.T) {
-	setupTestDB(t)
-	h := NewInstructionsHandler()
-
-	w, c := newPostRequest("/instructions", map[string]interface{}{
-		"scope": "global",
-		"title": "Has no content",
-	})
-
-	h.Create(c)
-
-	if w.Code != http.StatusBadRequest {
-		t.Fatalf("expected 400, got %d: %s", w.Code, w.Body.String())
-	}
-}
-
-func TestInstructionsCreate_InvalidScope(t *testing.T) {
-	setupTestDB(t)
-	h := NewInstructionsHandler()
-
-	w, c := newPostRequest("/instructions", map[string]interface{}{
-		"scope":   "team",
-		"title":   "Bad Scope",
-		"content": "Team scope is not supported yet.",
-	})
-
-	h.Create(c)
-
-	if w.Code != http.StatusBadRequest {
-		t.Fatalf("expected 400, got %d: %s", w.Code, w.Body.String())
-	}
-}
-
-func TestInstructionsCreate_WorkspaceScopeNoTarget(t *testing.T) {
-	setupTestDB(t)
-	h := NewInstructionsHandler()
-
-	w, c := newPostRequest("/instructions", map[string]interface{}{
-		"scope":   "workspace",
-		"title":   "Missing Target",
-		"content": "Workspace scope without scope_target.",
-	})
-
-	h.Create(c)
-
-	if w.Code != http.StatusBadRequest {
-		t.Fatalf("expected 400, got %d: %s", w.Code, w.Body.String())
-	}
-}
-
-func TestInstructionsCreate_ContentTooLong(t *testing.T) {
-	setupTestDB(t)
-	h := NewInstructionsHandler()
-
-	// Build a string longer than maxInstructionContentLen (8192).
-	longContent := string(make([]byte, maxInstructionContentLen+1))
-
-	w, c := newPostRequest("/instructions", map[string]interface{}{
-		"scope":   "global",
-		"title":   "Too Long",
-		"content": longContent,
-	})
-
-	h.Create(c)
-
-	if w.Code != http.StatusBadRequest {
-		t.Fatalf("expected 400, got %d: %s", w.Code, w.Body.String())
-	}
-}
-
-func TestInstructionsCreate_TitleTooLong(t *testing.T) {
-	setupTestDB(t)
-	h := NewInstructionsHandler()
-
-	longTitle := string(make([]byte, 201))
-
-	w, c := newPostRequest("/instructions", map[string]interface{}{
-		"scope":   "global",
-		"title":   longTitle,
-		"content": "Short content.",
-	})
-
-	h.Create(c)
-
-	if w.Code != http.StatusBadRequest {
-		t.Fatalf("expected 400, got %d: %s", w.Code, w.Body.String())
-	}
-}
-
-func TestInstructionsCreate_DBError(t *testing.T) {
-	mock := setupTestDB(t)
-	h := NewInstructionsHandler()
-
-	w, c := newPostRequest("/instructions", map[string]interface{}{
-		"scope":   "global",
-		"title":   "DB Error",
-		"content": "This will fail.",
-	})
-
-	mock.ExpectQuery("INSERT INTO platform_instructions").
-		WillReturnError(errors.New("connection refused"))
-
-	h.Create(c)
-
-	if w.Code != http.StatusInternalServerError {
-		t.Fatalf("expected 500, got %d: %s", w.Code, w.Body.String())
-	}
-	if err := mock.ExpectationsWereMet(); err != nil {
-		t.Errorf("unmet expectations: %v", err)
-	}
-}
-
-// ─── Update ──────────────────────────────────────────────────────────────────
-
-func TestInstructionsUpdate_ValidPartial(t *testing.T) {
-	mock := setupTestDB(t)
-	h := NewInstructionsHandler()
-
-	instID := "inst-update-1"
-	newTitle := "Updated Title"
-	w, c := newPutRequest("/instructions/"+instID, map[string]interface{}{
-		"title": newTitle,
-	})
-	c.Params = []gin.Param{{Key: "id", Value: instID}}
-
-	mock.ExpectExec("UPDATE platform_instructions SET").
-		WithArgs(&newTitle, sqlmock.AnyArg(), sqlmock.AnyArg(), sqlmock.AnyArg(), instID).
-		WillReturnResult(sqlmock.NewResult(0, 1))
-
-	h.Update(c)
-
-	if w.Code != http.StatusOK {
-		t.Fatalf("expected 200, got %d: %s", w.Code, w.Body.String())
-	}
-	if err := mock.ExpectationsWereMet(); err != nil {
-		t.Errorf("unmet expectations: %v", err)
-	}
-}
-
-func TestInstructionsUpdate_AllFields(t *testing.T) {
-	mock := setupTestDB(t)
-	h := NewInstructionsHandler()
-
-	instID := "inst-update-2"
-	title := "Full Update"
-	content := "New content body."
-	priority := 20
-	enabled := false
-	w, c := newPutRequest("/instructions/"+instID, map[string]interface{}{
-		"title":    title,
-		"content":  content,
-		"priority": priority,
-		"enabled":  enabled,
-	})
-	c.Params = []gin.Param{{Key: "id", Value: instID}}
-
-	mock.ExpectExec("UPDATE platform_instructions SET").
-		WithArgs(&title, &content, &priority, &enabled, instID).
-		WillReturnResult(sqlmock.NewResult(0, 1))
-
-	h.Update(c)
-
-	if w.Code != http.StatusOK {
-		t.Fatalf("expected 200, got %d: %s", w.Code, w.Body.String())
-	}
-	if err := mock.ExpectationsWereMet(); err != nil {
-		t.Errorf("unmet expectations: %v", err)
-	}
-}
-
-func TestInstructionsUpdate_ContentTooLong(t *testing.T) {
-	setupTestDB(t)
-	h := NewInstructionsHandler()
-
-	instID := "inst-too-long"
-	longContent := string(make([]byte, maxInstructionContentLen+1))
-	w, c := newPutRequest("/instructions/"+instID, map[string]interface{}{
-		"content": longContent,
-	})
-	c.Params = []gin.Param{{Key: "id", Value: instID}}
-
-	h.Update(c)
-
-	if w.Code != http.StatusBadRequest {
-		t.Fatalf("expected 400, got %d: %s", w.Code, w.Body.String())
-	}
-}
-
-func TestInstructionsUpdate_TitleTooLong(t *testing.T) {
-	setupTestDB(t)
-	h := NewInstructionsHandler()
-
-	instID := "inst-title-long"
-	longTitle := string(make([]byte, 201))
-	w, c := newPutRequest("/instructions/"+instID, map[string]interface{}{
-		"title": longTitle,
-	})
-	c.Params = []gin.Param{{Key: "id", Value: instID}}
-
-	h.Update(c)
-
-	if w.Code != http.StatusBadRequest {
-		t.Fatalf("expected 400, got %d: %s", w.Code, w.Body.String())
-	}
-}
-
-func TestInstructionsUpdate_NotFound(t *testing.T) {
-	mock := setupTestDB(t)
-	h := NewInstructionsHandler()
-
-	instID := "inst-missing"
-	w, c := newPutRequest("/instructions/"+instID, map[string]interface{}{
-		"title": "New Title",
-	})
-	c.Params = []gin.Param{{Key: "id", Value: instID}}
-
-	mock.ExpectExec("UPDATE platform_instructions SET").
-		WillReturnResult(sqlmock.NewResult(0, 0))
-
-	h.Update(c)
-
-	if w.Code != http.StatusNotFound {
-		t.Fatalf("expected 404, got %d: %s", w.Code, w.Body.String())
-	}
-	if err := mock.ExpectationsWereMet(); err != nil {
-		t.Errorf("unmet expectations: %v", err)
-	}
-}
-
-func TestInstructionsUpdate_DBError(t *testing.T) {
-	mock := setupTestDB(t)
-	h := NewInstructionsHandler()
-
-	instID := "inst-db-err"
-	w, c := newPutRequest("/instructions/"+instID, map[string]interface{}{
-		"title": "Error Update",
-	})
-	c.Params = []gin.Param{{Key: "id", Value: instID}}
-
-	mock.ExpectExec("UPDATE platform_instructions SET").
-		WillReturnError(errors.New("connection refused"))
-
-	h.Update(c)
-
-	if w.Code != http.StatusInternalServerError {
-		t.Fatalf("expected 500, got %d: %s", w.Code, w.Body.String())
-	}
-	if err := mock.ExpectationsWereMet(); err != nil {
-		t.Errorf("unmet expectations: %v", err)
-	}
-}
-
-// ─── Delete ───────────────────────────────────────────────────────────────────
-
-func TestInstructionsDelete_Valid(t *testing.T) {
-	mock := setupTestDB(t)
-	h := NewInstructionsHandler()
-
-	instID := "inst-delete-1"
-	w, c := newDeleteRequest("/instructions/" + instID)
-	c.Params = []gin.Param{{Key: "id", Value: instID}}
-
-	mock.ExpectExec("DELETE FROM platform_instructions WHERE id = $1").
-		WithArgs(instID).
-		WillReturnResult(sqlmock.NewResult(0, 1))
-
-	h.Delete(c)
-
-	if w.Code != http.StatusOK {
-		t.Fatalf("expected 200, got %d: %s", w.Code, w.Body.String())
-	}
-	if err := mock.ExpectationsWereMet(); err != nil {
-		t.Errorf("unmet expectations: %v", err)
-	}
-}
-
-func TestInstructionsDelete_NotFound(t *testing.T) {
-	mock := setupTestDB(t)
-	h := NewInstructionsHandler()
-
-	instID := "inst-not-there"
-	w, c := newDeleteRequest("/instructions/" + instID)
-	c.Params = []gin.Param{{Key: "id", Value: instID}}
-
-	mock.ExpectExec("DELETE FROM platform_instructions WHERE id = $1").
-		WithArgs(instID).
-		WillReturnResult(sqlmock.NewResult(0, 0))
-
-	h.Delete(c)
-
-	if w.Code != http.StatusNotFound {
-		t.Fatalf("expected 404, got %d: %s", w.Code, w.Body.String())
-	}
-	if err := mock.ExpectationsWereMet(); err != nil {
-		t.Errorf("unmet expectations: %v", err)
-	}
-}
-
-func TestInstructionsDelete_DBError(t *testing.T) {
-	mock := setupTestDB(t)
-	h := NewInstructionsHandler()
-
-	instID := "inst-del-err"
-	w, c := newDeleteRequest("/instructions/" + instID)
-	c.Params = []gin.Param{{Key: "id", Value: instID}}
-
-	mock.ExpectExec("DELETE FROM platform_instructions WHERE id = $1").
-		WillReturnError(errors.New("connection refused"))
-
-	h.Delete(c)
-
-	if w.Code != http.StatusInternalServerError {
-		t.Fatalf("expected 500, got %d: %s", w.Code, w.Body.String())
-	}
-	if err := mock.ExpectationsWereMet(); err != nil {
-		t.Errorf("unmet expectations: %v", err)
-	}
-}
-
-// ─── Resolve ──────────────────────────────────────────────────────────────────
-
-func TestInstructionsResolve_GlobalThenWorkspace(t *testing.T) {
-	mock := setupTestDB(t)
-	h := NewInstructionsHandler()
-
-	wsID := "ws-resolve-1"
-	w, c := newGetRequest("/workspaces/" + wsID + "/instructions/resolve")
-	c.Params = []gin.Param{{Key: "id", Value: wsID}}
-	c.Request = httptest.NewRequest(http.MethodGet, "/workspaces/"+wsID+"/instructions/resolve", nil)
-
-	now := time.Now()
-	rows := sqlmock.NewRows(resolveCols).
-		AddRow("global", "Be Helpful", "Always help the user.").
-		AddRow("global", "Stay on Topic", "Don't diverge.").
-		AddRow("workspace", "Use Claude Code", "Claude Code is the default runtime.")
-	mock.ExpectQuery("SELECT scope, title, content FROM platform_instructions").
-		WithArgs(wsID).
-		WillReturnRows(rows)
-
-	h.Resolve(c)
-
-	if w.Code != http.StatusOK {
-		t.Fatalf("expected 200, got %d: %s", w.Code, w.Body.String())
-	}
-	var out struct {
-		WorkspaceID   string `json:"workspace_id"`
-		Instructions string `json:"instructions"`
-	}
-	if err := json.Unmarshal(w.Body.Bytes(), &out); err != nil {
-		t.Fatalf("response not valid JSON: %v", err)
-	}
-	if out.WorkspaceID != wsID {
-		t.Errorf("expected workspace_id %s, got %s", wsID, out.WorkspaceID)
-	}
-	// Global section must come before workspace section.
-	if !bytes.Contains([]byte(out.Instructions), []byte("Platform-Wide Rules")) {
-		t.Error("instructions should contain 'Platform-Wide Rules' section")
-	}
-	if !bytes.Contains([]byte(out.Instructions), []byte("Role-Specific Rules")) {
-		t.Error("instructions should contain 'Role-Specific Rules' section")
-	}
-	// Global instructions must appear before workspace instructions.
-	idxGlobal := bytes.Index([]byte(out.Instructions), []byte("Platform-Wide Rules"))
-	idxWorkspace := bytes.Index([]byte(out.Instructions), []byte("Role-Specific Rules"))
-	if idxGlobal >= idxWorkspace {
-		t.Error("global section should appear before workspace section")
-	}
-	if err := mock.ExpectationsWereMet(); err != nil {
-		t.Errorf("unmet expectations: %v", err)
-	}
-}
-
-func TestInstructionsResolve_EmptyWorkspace(t *testing.T) {
-	mock := setupTestDB(t)
-	h := NewInstructionsHandler()
-
-	wsID := "ws-empty"
-	w, c := newGetRequest("/workspaces/" + wsID + "/instructions/resolve")
-	c.Params = []gin.Param{{Key: "id", Value: wsID}}
-	c.Request = httptest.NewRequest(http.MethodGet, "/workspaces/"+wsID+"/instructions/resolve", nil)
-
-	rows := sqlmock.NewRows(resolveCols)
-	mock.ExpectQuery("SELECT scope, title, content FROM platform_instructions").
-		WithArgs(wsID).
-		WillReturnRows(rows)
-
-	h.Resolve(c)
-
-	if w.Code != http.StatusOK {
-		t.Fatalf("expected 200, got %d: %s", w.Code, w.Body.String())
-	}
-	var out struct {
-		Instructions string `json:"instructions"`
-	}
-	if err := json.Unmarshal(w.Body.Bytes(), &out); err != nil {
-		t.Fatalf("response not valid JSON: %v", err)
-	}
-	// No rows → builder writes nothing; empty string returned.
-	if out.Instructions != "" {
-		t.Errorf("expected empty instructions for empty workspace, got: %q", out.Instructions)
-	}
-	if err := mock.ExpectationsWereMet(); err != nil {
-		t.Errorf("unmet expectations: %v", err)
-	}
-}
-
-func TestInstructionsResolve_DBError(t *testing.T) {
-	mock := setupTestDB(t)
-	h := NewInstructionsHandler()
-
-	wsID := "ws-err"
-	w, c := newGetRequest("/workspaces/" + wsID + "/instructions/resolve")
-	c.Params = []gin.Param{{Key: "id", Value: wsID}}
-	c.Request = httptest.NewRequest(http.MethodGet, "/workspaces/"+wsID+"/instructions/resolve", nil)
-
-	mock.ExpectQuery("SELECT scope, title, content FROM platform_instructions").
-		WithArgs(wsID).
-		WillReturnError(errors.New("connection refused"))
-
-	h.Resolve(c)
-
-	if w.Code != http.StatusInternalServerError {
-		t.Fatalf("expected 500, got %d: %s", w.Code, w.Body.String())
-	}
-	if err := mock.ExpectationsWereMet(); err != nil {
-		t.Errorf("unmet expectations: %v", err)
-	}
-}
-
-func TestInstructionsResolve_MissingWorkspaceID(t *testing.T) {
-	setupTestDB(t)
-	h := NewInstructionsHandler()
-
-	w, c := newGetRequest("/workspaces//instructions/resolve")
-	c.Params = []gin.Param{{Key: "id", Value: ""}}
-
-	h.Resolve(c)
-
-	if w.Code != http.StatusBadRequest {
-		t.Fatalf("expected 400, got %d: %s", w.Code, w.Body.String())
-	}
-}
-
-// ─── scanInstructions edge cases ───────────────────────────────────────────────
-
-func TestScanInstructions_ScanError(t *testing.T) {
-	// A mock rows object that returns a scan error on second row.
-	badRows := sqlmock.NewRows(instructionCols).
-		AddRow("inst-ok", "global", nil, "OK", "OK content", 10, true, time.Now(), time.Now()).
-		RowError(1, errors.New("scan error")).
-		AddRow("inst-bad", "global", nil, "Bad", "Bad content", 5, true, time.Now(), time.Now())
-
-	result := scanInstructions(badRows)
-	// First row should be captured; scan error is logged and skipped.
-	if len(result) != 1 || result[0].ID != "inst-ok" {
-		t.Errorf("expected 1 instruction (inst-ok), got: %v", result)
-	}
-}
-
-// ─── maxInstructionContentLen boundary ────────────────────────────────────────
-
-func TestInstructionsCreate_ContentExactlyAtLimit(t *testing.T) {
-	mock := setupTestDB(t)
-	h := NewInstructionsHandler()
-
-	exactContent := string(make([]byte, maxInstructionContentLen))
-	w, c := newPostRequest("/instructions", map[string]interface{}{
-		"scope":   "global",
-		"title":   "At Limit",
-		"content": exactContent,
-	})
-
-	mock.ExpectQuery("INSERT INTO platform_instructions").
-		WithArgs("global", nil, "At Limit", exactContent, 0).
-		WillReturnRows(sqlmock.NewRows([]string{"id"}).AddRow("at-limit-1"))
-
-	h.Create(c)
-
-	// Exactly at limit must succeed (8192 chars is acceptable).
-	if w.Code != http.StatusCreated {
-		t.Fatalf("expected 201 for content at limit, got %d: %s", w.Code, w.Body.String())
-	}
-	if err := mock.ExpectationsWereMet(); err != nil {
-		t.Errorf("unmet expectations: %v", err)
-	}
-}
-
-// ─── priority defaults ────────────────────────────────────────────────────────
-
-func TestInstructionsCreate_PriorityDefaultsToZero(t *testing.T) {
-	mock := setupTestDB(t)
-	h := NewInstructionsHandler()
-
-	// Body omits priority — expect it defaults to 0.
-	w, c := newPostRequest("/instructions", map[string]interface{}{
-		"scope":   "global",
-		"title":   "No Priority",
-		"content": "Default priority body.",
-	})
-
-	mock.ExpectQuery("INSERT INTO platform_instructions").
-		WithArgs("global", nil, "No Priority", "Default priority body.", 0).
-		WillReturnRows(sqlmock.NewRows([]string{"id"}).AddRow("no-prio-1"))
-
-	h.Create(c)
-
-	if w.Code != http.StatusCreated {
-		t.Fatalf("expected 201, got %d: %s", w.Code, w.Body.String())
-	}
-	if err := mock.ExpectationsWereMet(); err != nil {
-		t.Errorf("unmet expectations: %v", err)
-	}
-}
-
-// ─── nil scope_target for global instructions ─────────────────────────────────
-
-func TestInstructionsCreate_GlobalScopeNilTarget(t *testing.T) {
-	mock := setupTestDB(t)
-	h := NewInstructionsHandler()
-
-	w, c := newPostRequest("/instructions", map[string]interface{}{
-		"scope":   "global",
-		"title":   "Global Nil Target",
-		"content": "Global instruction.",
-	})
-
-	// For global scope, scope_target must be SQL NULL.
-	mock.ExpectQuery("INSERT INTO platform_instructions").
-		WithArgs("global", nil, "Global Nil Target", "Global instruction.", 0).
-		WillReturnRows(sqlmock.NewRows([]string{"id"}).AddRow("global-nil-1"))
-
-	h.Create(c)
-
-	if w.Code != http.StatusCreated {
-		t.Fatalf("expected 201, got %d: %s", w.Code, w.Body.String())
-	}
-	if err := mock.ExpectationsWereMet(); err != nil {
-		t.Errorf("unmet expectations: %v", err)
-	}
-}
-
-// ─── workspace scope with empty string target (rejected) ─────────────────────
-
-func TestInstructionsCreate_WorkspaceScopeEmptyStringTarget(t *testing.T) {
-	setupTestDB(t)
-	h := NewInstructionsHandler()
-
-	empty := ""
-	w, c := newPostRequest("/instructions", map[string]interface{}{
-		"scope":        "workspace",
-		"scope_target": empty,
-		"title":        "Empty Target",
-		"content":      "Empty workspace target.",
-	})
-
-	h.Create(c)
-
-	if w.Code != http.StatusBadRequest {
-		t.Fatalf("expected 400 for empty string scope_target, got %d: %s", w.Code, w.Body.String())
-	}
-}
-
-// ─── Resolve: scope label transitions ────────────────────────────────────────
-
-func TestInstructionsResolve_ScopeTransitionOnlyGlobal(t *testing.T) {
-	mock := setupTestDB(t)
-	h := NewInstructionsHandler()
-
-	wsID := "ws-only-global"
-	w, c := newGetRequest("/workspaces/" + wsID + "/instructions/resolve")
-	c.Params = []gin.Param{{Key: "id", Value: wsID}}
-	c.Request = httptest.NewRequest(http.MethodGet, "/workspaces/"+wsID+"/instructions/resolve", nil)
-
-	rows := sqlmock.NewRows(resolveCols).
-		AddRow("global", "Rule One", "First rule.").
-		AddRow("global", "Rule Two", "Second rule.")
-	mock.ExpectQuery("SELECT scope, title, content FROM platform_instructions").
-		WithArgs(wsID).
-		WillReturnRows(rows)
-
-	h.Resolve(c)
-
-	if w.Code != http.StatusOK {
-		t.Fatalf("expected 200, got %d: %s", w.Code, w.Body.String())
-	}
-	var out struct {
-		Instructions string `json:"instructions"`
-	}
-	if err := json.Unmarshal(w.Body.Bytes(), &out); err != nil {
-		t.Fatalf("response not valid JSON: %v", err)
-	}
-	// Two global instructions share one section header.
-	if bytes.Count([]byte(out.Instructions), []byte("Platform-Wide Rules")) != 1 {
-		t.Error("expect exactly one 'Platform-Wide Rules' header for consecutive global rows")
-	}
-	if err := mock.ExpectationsWereMet(); err != nil {
-		t.Errorf("unmet expectations: %v", err)
-	}
-}
-
-// ─── Update: empty body (all nil — no-op update) ─────────────────────────────
-
-func TestInstructionsUpdate_EmptyBody(t *testing.T) {
-	mock := setupTestDB(t)
-	h := NewInstructionsHandler()
-
-	instID := "inst-empty-update"
-	w, c := newPutRequest("/instructions/"+instID, map[string]interface{}{})
-	c.Params = []gin.Param{{Key: "id", Value: instID}}
-
-	// COALESCE(nil, ...) = unchanged; still updates updated_at.
-	mock.ExpectExec("UPDATE platform_instructions SET").
-		WithArgs(sqlmock.AnyArg(), sqlmock.AnyArg(), sqlmock.AnyArg(), sqlmock.AnyArg(), instID).
-		WillReturnResult(sqlmock.NewResult(0, 1))
-
-	h.Update(c)
-
-	if w.Code != http.StatusOK {
-		t.Fatalf("expected 200 for empty body, got %d: %s", w.Code, w.Body.String())
-	}
-	if err := mock.ExpectationsWereMet(); err != nil {
-		t.Errorf("unmet expectations: %v", err)
-	}
-}

workspace-server/internal/handlers/plugins_atomic_tar_test.go

@@ -0,0 +1,310 @@
+package handlers
+
+// plugins_atomic_tar_test.go — unit tests for tarWalk (the only non-trivial
+// function in plugins_atomic_tar.go). The file contains only pure tar-walk
+// logic with no DB or HTTP dependencies, so tests use real temp directories
+// with no mocking.
+
+import (
+	"archive/tar"
+	"bytes"
+	"io"
+	"os"
+	"path/filepath"
+	"strings"
+	"testing"
+)
+
+// ─── newTarWriter ─────────────────────────────────────────────────────────────
+
+func TestNewTarWriter_Basic(t *testing.T) {
+	var buf bytes.Buffer
+	tw := newTarWriter(&buf)
+	if tw == nil {
+		t.Fatal("newTarWriter returned nil")
+	}
+	// Write a header to prove the writer is functional.
+	hdr := &tar.Header{
+		Name: "test.txt",
+		Mode: 0644,
+		Size: 5,
+	}
+	if err := tw.WriteHeader(hdr); err != nil {
+		t.Fatalf("WriteHeader failed: %v", err)
+	}
+	if _, err := tw.Write([]byte("hello")); err != nil {
+		t.Fatalf("Write failed: %v", err)
+	}
+	if err := tw.Close(); err != nil {
+		t.Fatalf("Close failed: %v", err)
+	}
+}
+
+// ─── tarWalk: empty directory ─────────────────────────────────────────────────
+
+func TestTarWalk_EmptyDir(t *testing.T) {
+	tmp := t.TempDir()
+	var buf bytes.Buffer
+	tw := tar.NewWriter(&buf)
+
+	if err := tarWalk(tmp, "prefix", tw); err != nil {
+		t.Fatalf("tarWalk error: %v", err)
+	}
+	if err := tw.Close(); err != nil {
+		t.Fatalf("tw.Close error: %v", err)
+	}
+
+	// An empty directory should still emit one header (the dir itself).
+	rdr := tar.NewReader(&buf)
+	hdr, err := rdr.Next()
+	if err != nil {
+		t.Fatalf("expected at least the dir header, got error: %v", err)
+	}
+	if !strings.HasSuffix(hdr.Name, "/") {
+		t.Errorf("expected directory name ending in '/', got %q", hdr.Name)
+	}
+
+	// No more entries.
+	if _, err := rdr.Next(); err != io.EOF {
+		t.Errorf("expected only one header, got more: %v", err)
+	}
+}
+
+// ─── tarWalk: single file ─────────────────────────────────────────────────────
+
+func TestTarWalk_SingleFile(t *testing.T) {
+	tmp := t.TempDir()
+	if err := os.WriteFile(filepath.Join(tmp, "hello.txt"), []byte("world"), 0644); err != nil {
+		t.Fatal(err)
+	}
+
+	var buf bytes.Buffer
+	tw := tar.NewWriter(&buf)
+	if err := tarWalk(tmp, "mydir", tw); err != nil {
+		t.Fatalf("tarWalk error: %v", err)
+	}
+	if err := tw.Close(); err != nil {
+		t.Fatal(err)
+	}
+
+	// Should have 2 entries: the dir prefix, then hello.txt.
+	entries := 0
+	names := []string{}
+	rdr := tar.NewReader(&buf)
+	for {
+		hdr, err := rdr.Next()
+		if err == io.EOF {
+			break
+		}
+		if err != nil {
+			t.Fatalf("unexpected error reading tar: %v", err)
+		}
+		entries++
+		names = append(names, hdr.Name)
+
+		if hdr.Name == "mydir/hello.txt" {
+			if hdr.Size != 5 {
+				t.Errorf("expected size 5, got %d", hdr.Size)
+			}
+			content := make([]byte, 5)
+			if _, err := rdr.Read(content); err != nil && err != io.EOF {
+				t.Fatalf("read error: %v", err)
+			}
+			if string(content) != "world" {
+				t.Errorf("expected 'world', got %q", string(content))
+			}
+		}
+	}
+	if entries != 2 {
+		t.Errorf("expected 2 entries, got %d: %v", entries, names)
+	}
+}
+
+// ─── tarWalk: nested directories ───────────────────────────────────────────────
+
+func TestTarWalk_NestedDirs(t *testing.T) {
+	tmp := t.TempDir()
+	subdir := filepath.Join(tmp, "a", "b", "c")
+	if err := os.MkdirAll(subdir, 0755); err != nil {
+		t.Fatal(err)
+	}
+	if err := os.WriteFile(filepath.Join(subdir, "deep.txt"), []byte("nested"), 0644); err != nil {
+		t.Fatal(err)
+	}
+
+	var buf bytes.Buffer
+	tw := tar.NewWriter(&buf)
+	if err := tarWalk(tmp, "root", tw); err != nil {
+		t.Fatalf("tarWalk error: %v", err)
+	}
+	if err := tw.Close(); err != nil {
+		t.Fatal(err)
+	}
+
+	// Collect all file paths (not dirs) with content.
+	files := map[string]string{}
+	rdr := tar.NewReader(&buf)
+	for {
+		hdr, err := rdr.Next()
+		if err == io.EOF {
+			break
+		}
+		if err != nil {
+			t.Fatal(err)
+		}
+		if !strings.HasSuffix(hdr.Name, "/") && hdr.Size > 0 {
+			content := make([]byte, hdr.Size)
+			rdr.Read(content)
+			files[hdr.Name] = string(content)
+		}
+	}
+
+	expected := "root/a/b/c/deep.txt"
+	if _, ok := files[expected]; !ok {
+		t.Errorf("expected file %q in tar; got: %v", expected, files)
+	} else if files[expected] != "nested" {
+		t.Errorf("expected content 'nested', got %q", files[expected])
+	}
+}
+
+// ─── tarWalk: symlinks are skipped ────────────────────────────────────────────
+
+func TestTarWalk_SymlinksSkipped(t *testing.T) {
+	tmp := t.TempDir()
+
+	// Create a real file.
+	realPath := filepath.Join(tmp, "real.txt")
+	if err := os.WriteFile(realPath, []byte("real content"), 0644); err != nil {
+		t.Fatal(err)
+	}
+
+	// Create a symlink to it.
+	linkPath := filepath.Join(tmp, "link.txt")
+	if err := os.Symlink(realPath, linkPath); err != nil {
+		t.Fatal(err)
+	}
+
+	var buf bytes.Buffer
+	tw := tar.NewWriter(&buf)
+	if err := tarWalk(tmp, "prefix", tw); err != nil {
+		t.Fatalf("tarWalk error: %v", err)
+	}
+	if err := tw.Close(); err != nil {
+		t.Fatal(err)
+	}
+
+	// Only real.txt should appear; link.txt should be absent.
+	names := []string{}
+	rdr := tar.NewReader(&buf)
+	for {
+		hdr, err := rdr.Next()
+		if err == io.EOF {
+			break
+		}
+		if err != nil {
+			t.Fatal(err)
+		}
+		names = append(names, hdr.Name)
+	}
+
+	foundLink := false
+	for _, n := range names {
+		if strings.Contains(n, "link") {
+			foundLink = true
+		}
+	}
+	if foundLink {
+		t.Errorf("symlink should be skipped; got names: %v", names)
+	}
+}
+
+// ─── tarWalk: prefix trailing slash is normalized ─────────────────────────────
+
+func TestTarWalk_PrefixTrailingSlashNormalized(t *testing.T) {
+	tmp := t.TempDir()
+	if err := os.WriteFile(filepath.Join(tmp, "f.txt"), []byte("x"), 0644); err != nil {
+		t.Fatal(err)
+	}
+
+	var buf bytes.Buffer
+	tw := tar.NewWriter(&buf)
+	// Pass prefix WITH trailing slash — should produce same archive as without.
+	if err := tarWalk(tmp, "foo/", tw); err != nil {
+		t.Fatal(err)
+	}
+	if err := tw.Close(); err != nil {
+		t.Fatal(err)
+	}
+
+	// The file should be under "foo/", not "foo//".
+	rdr := tar.NewReader(&buf)
+	for {
+		hdr, err := rdr.Next()
+		if err == io.EOF {
+			break
+		}
+		if err != nil {
+			t.Fatal(err)
+		}
+		if !strings.HasSuffix(hdr.Name, "/") && strings.Contains(hdr.Name, "f.txt") {
+			if strings.Contains(hdr.Name, "//") {
+				t.Errorf("double slash found in path %q — trailing slash not normalized", hdr.Name)
+			}
+			if !strings.HasPrefix(hdr.Name, "foo/") {
+				t.Errorf("expected path to start with 'foo/', got %q", hdr.Name)
+			}
+		}
+	}
+}
+
+// ─── tarWalk: prefix = "." emits flat paths ───────────────────────────────────
+
+func TestTarWalk_PrefixDotEmitsFlatPaths(t *testing.T) {
+	tmp := t.TempDir()
+	subdir := filepath.Join(tmp, "sub")
+	if err := os.MkdirAll(subdir, 0755); err != nil {
+		t.Fatal(err)
+	}
+	if err := os.WriteFile(filepath.Join(subdir, "file.txt"), []byte("data"), 0644); err != nil {
+		t.Fatal(err)
+	}
+
+	var buf bytes.Buffer
+	tw := tar.NewWriter(&buf)
+	if err := tarWalk(tmp, ".", tw); err != nil {
+		t.Fatal(err)
+	}
+	if err := tw.Close(); err != nil {
+		t.Fatal(err)
+	}
+
+	// With prefix ".", paths should NOT start with "./" (filepath.Clean normalizes it).
+	rdr := tar.NewReader(&buf)
+	for {
+		hdr, err := rdr.Next()
+		if err == io.EOF {
+			break
+		}
+		if err != nil {
+			t.Fatal(err)
+		}
+		if !strings.HasSuffix(hdr.Name, "/") && strings.Contains(hdr.Name, "file.txt") {
+			if strings.HasPrefix(hdr.Name, "./") {
+				t.Errorf("prefix '.' should not emit './' prefix; got %q", hdr.Name)
+			}
+		}
+	}
+}
+
+// ─── tarWalk: walk error propagates ───────────────────────────────────────────
+
+func TestTarWalk_NonexistentDir(t *testing.T) {
+	nonexistent := filepath.Join(t.TempDir(), "does-not-exist")
+	var buf bytes.Buffer
+	tw := tar.NewWriter(&buf)
+
+	err := tarWalk(nonexistent, "x", tw)
+	if err == nil {
+		t.Error("expected error for nonexistent directory, got nil")
+	}
+}