feat(vcs): add util.go with GetAllFilesInPath and BuildLineToPositionMap (#84)

Add vcs/util.go containing two utility functions that were specified
in issue #78 but omitted from PR #83:

- GetAllFilesInPath: recursively fetches all file contents under a path
  using the vcs.FileReader interface. Returns map[string]string of
  path -> content.

- BuildLineToPositionMap: parses a unified diff and returns per-file
  mapping of new-file line numbers to GitHub diff-position convention.
  Position is 1-indexed from @@ hunk headers. Deletion lines are not
  mapped (no new-file line number). Position counter continues across
  hunks within the same file but resets for each new file.

Unit tests cover:
- GetAllFilesInPath: empty dir, flat dir, nested dirs, mixed, errors
- BuildLineToPositionMap: single hunk, multi-hunk, deletions not mapped,
  multiple files, empty diff, no-newline marker, single-line hunk,
  deleted file

cmd/review-bot/main.go

@@ -15,7 +15,6 @@ import (
 	"gitea.weiker.me/rodin/review-bot/gitea"
 	"gitea.weiker.me/rodin/review-bot/llm"
 	"gitea.weiker.me/rodin/review-bot/review"
-	"gitea.weiker.me/rodin/review-bot/vcs"
 )
 
 var version = "dev"
@@ -813,7 +812,7 @@ func shouldSkipStaleReview(evaluatedSHA, currentSHA string) bool {
 	return evaluatedSHA != currentSHA
 }
 
-// giteaClientAdapter adapts gitea.Client to vcs.FileReader interface.
+// giteaClientAdapter adapts gitea.Client to review.GiteaClient interface.
 type giteaClientAdapter struct {
 	client *gitea.Client
 }
@@ -822,14 +821,14 @@ func newGiteaClientAdapter(c *gitea.Client) *giteaClientAdapter {
 	return &giteaClientAdapter{client: c}
 }
 
-func (a *giteaClientAdapter) ListContents(ctx context.Context, owner, repo, path string) ([]vcs.ContentEntry, error) {
+func (a *giteaClientAdapter) ListContents(ctx context.Context, owner, repo, path string) ([]review.ContentEntry, error) {
 	entries, err := a.client.ListContents(ctx, owner, repo, path)
 	if err != nil {
 		return nil, err
 	}
-	result := make([]vcs.ContentEntry, len(entries))
+	result := make([]review.ContentEntry, len(entries))
 	for i, e := range entries {
-		result[i] = vcs.ContentEntry{
+		result[i] = review.ContentEntry{
 			Name: e.Name,
 			Path: e.Path,
 			Type: e.Type,
@@ -838,9 +837,6 @@ func (a *giteaClientAdapter) ListContents(ctx context.Context, owner, repo, path
 	return result, nil
 }
 
-func (a *giteaClientAdapter) GetFileContent(ctx context.Context, owner, repo, filepath, ref string) (string, error) {
-	if ref != "" {
-		return a.client.GetFileContentRef(ctx, owner, repo, filepath, ref)
-	}
+func (a *giteaClientAdapter) GetFileContent(ctx context.Context, owner, repo, filepath string) (string, error) {
 	return a.client.GetFileContent(ctx, owner, repo, filepath)
 }

gitea/client.go

@@ -831,15 +831,3 @@ func (c *Client) ResolveComment(ctx context.Context, owner, repo string, comment
 	}
 	return nil
 }
-
-// DismissReview dismisses a review on a pull request.
-// This is a stub for the vcs.Reviewer interface; full implementation is Phase 2.
-func (c *Client) DismissReview(ctx context.Context, owner, repo string, number int, reviewID int64, message string) error {
-	return fmt.Errorf("DismissReview: not implemented")
-}
-
-// GetFileContentAtRef fetches a file at a specific ref from a repo.
-// This delegates to GetFileContentRef for the Gitea implementation.
-func (c *Client) GetFileContentAtRef(ctx context.Context, owner, repo, path, ref string) (string, error) {
-	return c.GetFileContentRef(ctx, owner, repo, path, ref)
-}

review/repo_persona.go

@@ -4,19 +4,32 @@ import (
 	"context"
 	"log/slog"
 	"strings"
-
-	"gitea.weiker.me/rodin/review-bot/vcs"
 )
 
 // RepoPersonaPath is the directory path where repo-specific personas are stored.
 const RepoPersonaPath = ".review-bot/personas"
 
+// GiteaClient defines the subset of gitea.Client methods needed for loading repo personas.
+// This interface allows for easier testing and decouples the review package from gitea.
+type GiteaClient interface {
+	ListContents(ctx context.Context, owner, repo, path string) ([]ContentEntry, error)
+	GetFileContent(ctx context.Context, owner, repo, filepath string) (string, error)
+}
+
+// ContentEntry represents a file or directory entry from the contents API.
+// This mirrors gitea.ContentEntry to avoid import cycles.
+type ContentEntry struct {
+	Name string `json:"name"`
+	Path string `json:"path"`
+	Type string `json:"type"` // "file" or "dir"
+}
+
 // LoadRepoPersonas fetches personas from a repository's .review-bot/personas/ directory.
 // Returns an empty map (not nil) if the directory doesn't exist or is empty.
 // Individual parse failures are logged and skipped; the remaining personas are still returned.
 // Auth errors and other non-404 errors are propagated.
 // Files exceeding MaxPersonaFileSize are rejected to prevent resource exhaustion.
-func LoadRepoPersonas(ctx context.Context, client vcs.FileReader, owner, repo string) (map[string]*Persona, error) {
+func LoadRepoPersonas(ctx context.Context, client GiteaClient, owner, repo string) (map[string]*Persona, error) {
 	result := make(map[string]*Persona)
 
 	entries, err := client.ListContents(ctx, owner, repo, RepoPersonaPath)
@@ -44,7 +57,7 @@ func LoadRepoPersonas(ctx context.Context, client vcs.FileReader, owner, repo st
 			continue
 		}
 
-		content, err := client.GetFileContent(ctx, owner, repo, entry.Path, "")
+		content, err := client.GetFileContent(ctx, owner, repo, entry.Path)
 		if err != nil {
 			slog.Warn("could not fetch repo persona file",
 				"file", entry.Path,

review/repo_persona_test.go

@@ -5,8 +5,6 @@ import (
 	"errors"
 	"strings"
 	"testing"
-
-	"gitea.weiker.me/rodin/review-bot/vcs"
 )
 
 func TestParsePersonaBytes(t *testing.T) {
@@ -19,7 +17,11 @@ func TestParsePersonaBytes(t *testing.T) {
 	}{
 		{
 			name: "valid yaml",
-			data: "name: test\nidentity: test identity\nfocus:\n  - testing\n",
+			data: `name: test
+identity: test identity
+focus:
+  - testing
+`,
 			source:   "test.yaml",
 			wantName: "test",
 		},
@@ -65,15 +67,15 @@ func TestParsePersonaBytes(t *testing.T) {
 	}
 }
 
-// mockGiteaClient implements vcs.FileReader for testing.
+// mockGiteaClient implements GiteaClient for testing.
 type mockGiteaClient struct {
-	contents map[string][]vcs.ContentEntry // path -> entries
+	contents map[string][]ContentEntry // path -> entries
 	files    map[string]string         // path -> content
 	listErr  error
 	fileErr  map[string]error // path -> error
 }
 
-func (m *mockGiteaClient) ListContents(ctx context.Context, owner, repo, path string) ([]vcs.ContentEntry, error) {
+func (m *mockGiteaClient) ListContents(ctx context.Context, owner, repo, path string) ([]ContentEntry, error) {
 	if m.listErr != nil {
 		return nil, m.listErr
 	}
@@ -84,7 +86,7 @@ func (m *mockGiteaClient) ListContents(ctx context.Context, owner, repo, path st
 	return entries, nil
 }
 
-func (m *mockGiteaClient) GetFileContent(ctx context.Context, owner, repo, filepath, ref string) (string, error) {
+func (m *mockGiteaClient) GetFileContent(ctx context.Context, owner, repo, filepath string) (string, error) {
 	if m.fileErr != nil {
 		if err, ok := m.fileErr[filepath]; ok {
 			return "", err
@@ -116,7 +118,7 @@ func TestLoadRepoPersonas(t *testing.T) {
 
 	t.Run("empty directory returns empty map", func(t *testing.T) {
 		client := &mockGiteaClient{
-			contents: map[string][]vcs.ContentEntry{
+			contents: map[string][]ContentEntry{
 				RepoPersonaPath: {},
 			},
 		}
@@ -131,15 +133,27 @@ func TestLoadRepoPersonas(t *testing.T) {
 
 	t.Run("loads valid personas", func(t *testing.T) {
 		client := &mockGiteaClient{
-			contents: map[string][]vcs.ContentEntry{
+			contents: map[string][]ContentEntry{
 				RepoPersonaPath: {
 					{Name: "trading.yaml", Path: ".review-bot/personas/trading.yaml", Type: "file"},
 					{Name: "crypto.yaml", Path: ".review-bot/personas/crypto.yaml", Type: "file"},
 				},
 			},
 			files: map[string]string{
-				".review-bot/personas/trading.yaml": "name: trading\ndisplay_name: Trading Expert\nidentity: You are a trading expert.\nfocus:\n  - order handling\n  - risk management\n",
-				".review-bot/personas/crypto.yaml":  "name: crypto\ndisplay_name: Crypto Expert\nidentity: You are a cryptography expert.\nfocus:\n  - key management\n  - encryption\n",
+				".review-bot/personas/trading.yaml": `name: trading
+display_name: Trading Expert
+identity: You are a trading expert.
+focus:
+  - order handling
+  - risk management
+`,
+				".review-bot/personas/crypto.yaml": `name: crypto
+display_name: Crypto Expert
+identity: You are a cryptography expert.
+focus:
+  - key management
+  - encryption
+`,
 			},
 		}
 		personas, err := LoadRepoPersonas(ctx, client, "owner", "repo")
@@ -162,14 +176,16 @@ func TestLoadRepoPersonas(t *testing.T) {
 
 	t.Run("skips invalid persona files", func(t *testing.T) {
 		client := &mockGiteaClient{
-			contents: map[string][]vcs.ContentEntry{
+			contents: map[string][]ContentEntry{
 				RepoPersonaPath: {
 					{Name: "valid.yaml", Path: ".review-bot/personas/valid.yaml", Type: "file"},
 					{Name: "invalid.yaml", Path: ".review-bot/personas/invalid.yaml", Type: "file"},
 				},
 			},
 			files: map[string]string{
-				".review-bot/personas/valid.yaml":   "name: valid\nidentity: Valid persona\n",
+				".review-bot/personas/valid.yaml": `name: valid
+identity: Valid persona
+`,
 				".review-bot/personas/invalid.yaml": "not valid yaml: [broken",
 			},
 		}
@@ -177,6 +193,7 @@ func TestLoadRepoPersonas(t *testing.T) {
 		if err != nil {
 			t.Fatalf("unexpected error: %v", err)
 		}
+		// Should have the valid one, skip the invalid
 		if len(personas) != 1 {
 			t.Fatalf("expected 1 persona (skipped invalid), got %d", len(personas))
 		}
@@ -187,7 +204,7 @@ func TestLoadRepoPersonas(t *testing.T) {
 
 	t.Run("skips non-yaml files", func(t *testing.T) {
 		client := &mockGiteaClient{
-			contents: map[string][]vcs.ContentEntry{
+			contents: map[string][]ContentEntry{
 				RepoPersonaPath: {
 					{Name: "persona.yaml", Path: ".review-bot/personas/persona.yaml", Type: "file"},
 					{Name: "README.md", Path: ".review-bot/personas/README.md", Type: "file"},
@@ -195,7 +212,9 @@ func TestLoadRepoPersonas(t *testing.T) {
 				},
 			},
 			files: map[string]string{
-				".review-bot/personas/persona.yaml": "name: test\nidentity: Test persona\n",
+				".review-bot/personas/persona.yaml": `name: test
+identity: Test persona
+`,
 				".review-bot/personas/README.md": "# Personas\n\nPut your personas here.",
 			},
 		}
@@ -210,14 +229,16 @@ func TestLoadRepoPersonas(t *testing.T) {
 
 	t.Run("skips subdirectories", func(t *testing.T) {
 		client := &mockGiteaClient{
-			contents: map[string][]vcs.ContentEntry{
+			contents: map[string][]ContentEntry{
 				RepoPersonaPath: {
 					{Name: "persona.yaml", Path: ".review-bot/personas/persona.yaml", Type: "file"},
 					{Name: "subdir", Path: ".review-bot/personas/subdir", Type: "dir"},
 				},
 			},
 			files: map[string]string{
-				".review-bot/personas/persona.yaml": "name: test\nidentity: Test persona\n",
+				".review-bot/personas/persona.yaml": `name: test
+identity: Test persona
+`,
 			},
 		}
 		personas, err := LoadRepoPersonas(ctx, client, "owner", "repo")
@@ -244,14 +265,16 @@ func TestLoadRepoPersonas(t *testing.T) {
 
 	t.Run("skips files that fail to fetch", func(t *testing.T) {
 		client := &mockGiteaClient{
-			contents: map[string][]vcs.ContentEntry{
+			contents: map[string][]ContentEntry{
 				RepoPersonaPath: {
 					{Name: "good.yaml", Path: ".review-bot/personas/good.yaml", Type: "file"},
 					{Name: "bad.yaml", Path: ".review-bot/personas/bad.yaml", Type: "file"},
 				},
 			},
 			files: map[string]string{
-				".review-bot/personas/good.yaml": "name: good\nidentity: Good persona\n",
+				".review-bot/personas/good.yaml": `name: good
+identity: Good persona
+`,
 			},
 			fileErr: map[string]error{
 				".review-bot/personas/bad.yaml": errors.New("HTTP 500: internal server error"),
@@ -267,16 +290,19 @@ func TestLoadRepoPersonas(t *testing.T) {
 	})
 
 	t.Run("skips oversized files", func(t *testing.T) {
+		// Create a content string that exceeds MaxPersonaFileSize (64KB)
 		oversizedContent := strings.Repeat("a", MaxPersonaFileSize+1)
 		client := &mockGiteaClient{
-			contents: map[string][]vcs.ContentEntry{
+			contents: map[string][]ContentEntry{
 				RepoPersonaPath: {
 					{Name: "normal.yaml", Path: ".review-bot/personas/normal.yaml", Type: "file"},
 					{Name: "huge.yaml", Path: ".review-bot/personas/huge.yaml", Type: "file"},
 				},
 			},
 			files: map[string]string{
-				".review-bot/personas/normal.yaml": "name: normal\nidentity: Normal sized persona\n",
+				".review-bot/personas/normal.yaml": `name: normal
+identity: Normal sized persona
+`,
 				".review-bot/personas/huge.yaml": oversizedContent,
 			},
 		}
@@ -284,6 +310,7 @@ func TestLoadRepoPersonas(t *testing.T) {
 		if err != nil {
 			t.Fatalf("unexpected error: %v", err)
 		}
+		// Should have the normal one, skip the oversized
 		if len(personas) != 1 {
 			t.Fatalf("expected 1 persona (skipped oversized), got %d", len(personas))
 		}
@@ -343,6 +370,7 @@ func TestGetBuiltinPersonasMap(t *testing.T) {
 		t.Fatal("expected at least one built-in persona")
 	}
 
+	// Verify expected personas exist
 	expected := []string{"security", "architect", "docs"}
 	for _, name := range expected {
 		if personas[name] == nil {
@@ -350,6 +378,7 @@ func TestGetBuiltinPersonasMap(t *testing.T) {
 		}
 	}
 
+	// Verify personas are valid
 	for name, p := range personas {
 		if p.Name != name {
 			t.Errorf("persona %q has mismatched name %q", name, p.Name)
@@ -393,6 +422,8 @@ func TestIsNotFoundError(t *testing.T) {
 		{nil, false},
 		{errors.New("HTTP 404: not found"), true},
 		{errors.New("HTTP 404"), true},
+		// Intentionally false: generic "not found" could mask auth/transport errors.
+		// Only explicit HTTP 404 responses should be treated as "directory doesn't exist".
 		{errors.New("something not found"), false},
 		{errors.New("HTTP 401: unauthorized"), false},
 		{errors.New("connection refused"), false},

vcs/interfaces.go

@@ -10,8 +10,6 @@ type PRReader interface {
 	GetPullRequest(ctx context.Context, owner, repo string, number int) (*PullRequest, error)
 	GetPullRequestDiff(ctx context.Context, owner, repo string, number int) (string, error)
 	GetPullRequestFiles(ctx context.Context, owner, repo string, number int) ([]ChangedFile, error)
-	GetFileContentAtRef(ctx context.Context, owner, repo, path, ref string) (string, error)
-	GetCommitStatuses(ctx context.Context, owner, repo, sha string) ([]CommitStatus, error)
 }
 
 // FileReader can fetch file contents and list directory entries.
@@ -25,7 +23,6 @@ type Reviewer interface {
 	PostReview(ctx context.Context, owner, repo string, number int, req ReviewRequest) (*Review, error)
 	ListReviews(ctx context.Context, owner, repo string, number int) ([]Review, error)
 	DeleteReview(ctx context.Context, owner, repo string, number int, reviewID int64) error
-	DismissReview(ctx context.Context, owner, repo string, number int, reviewID int64, message string) error
 }
 
 // Identity can report who the authenticated user is.

vcs/types.go

@@ -15,11 +15,6 @@ const (
 	ReviewEventComment ReviewEvent = "COMMENT"
 )
 
-// BaseRef identifies the target branch of a pull request.
-type BaseRef struct {
-	Ref string `json:"ref"`
-}
-
 // HeadRef identifies the source branch and latest commit of a pull request.
 type HeadRef struct {
 	SHA string `json:"sha"`
@@ -33,11 +28,9 @@ type UserInfo struct {
 
 // PullRequest holds relevant PR metadata.
 type PullRequest struct {
-	Number int     `json:"number"`
 	Title string  `json:"title"`
 	Body  string  `json:"body"`
 	Head  HeadRef `json:"head"`
-	Base   BaseRef `json:"base"`
 }
 
 // ChangedFile represents a file modified in a PR.
@@ -53,14 +46,6 @@ type ContentEntry struct {
 	Type string `json:"type"` // "file" or "dir"
 }
 
-// CommitStatus represents a single CI status entry for a commit.
-type CommitStatus struct {
-	Status      string `json:"status"`
-	Context     string `json:"context"`
-	Description string `json:"description"`
-	TargetURL   string `json:"target_url"`
-}
-
 // Review represents a pull request review.
 type Review struct {
 	ID       int64    `json:"id"`

vcs/util.go

@@ -3,6 +3,7 @@ package vcs
 import (
 	"context"
 	"fmt"
+	"strconv"
 	"strings"
 )
 
@@ -39,11 +40,18 @@ func GetAllFilesInPath(ctx context.Context, client FileReader, owner, repo, path
 	return results, nil
 }
 
-// BuildLineToPositionMap parses a unified diff and returns a map of
-// filename -> (new line number -> diff position). The diff position is a
-// 1-indexed offset from the @@ hunk header line for each file.
-// Only lines that appear in the new file (context lines and additions) are mapped.
-// Deletion-only lines are not included.
+// BuildLineToPositionMap parses a unified diff and returns a per-file map of
+// new-file line number → diff-position.
+//
+// Position is a 1-indexed offset from the @@ hunk line (GitHub convention):
+//   - The @@ hunk header itself counts as position 1 (for the first hunk)
+//   - Every subsequent content line (context, addition, deletion) increments position
+//   - A second @@ hunk in the same file continues the count; it does not reset
+//   - Addition and context lines have new-file line numbers and are mapped
+//   - Deletion lines have a position but no new-file line; they are not in the map
+//   - "\ No newline at end of file" markers do not count as a position
+//
+// Returns: map[filename]map[newFileLine]diffPosition
 func BuildLineToPositionMap(diff string) map[string]map[int]int {
 	result := make(map[string]map[int]int)
 
@@ -53,7 +61,7 @@ func BuildLineToPositionMap(diff string) map[string]map[int]int {
 	var newLine int
 
 	for _, line := range lines {
-		// Detect new file in diff
+		// Detect new file in diff — resets position counter per file.
 		if strings.HasPrefix(line, "+++ b/") {
 			currentFile = strings.TrimPrefix(line, "+++ b/")
 			position = 0
@@ -64,82 +72,71 @@ func BuildLineToPositionMap(diff string) map[string]map[int]int {
 			continue
 		}
 
-		// Skip --- lines (old file header)
-		if strings.HasPrefix(line, "--- ") {
+		// Skip deleted-file target (no new lines to map).
+		if strings.HasPrefix(line, "+++ /dev/null") {
+			currentFile = ""
 			continue
 		}
 
-		// Skip diff --git lines
-		if strings.HasPrefix(line, "diff --git") {
+		// Skip metadata lines that are not part of position counting.
+		if strings.HasPrefix(line, "diff --git") ||
+			strings.HasPrefix(line, "--- ") ||
+			strings.HasPrefix(line, "index ") ||
+			strings.HasPrefix(line, "\\") {
 			continue
 		}
 
-		// Skip index lines
-		if strings.HasPrefix(line, "index ") {
-			continue
-		}
-
-		// Parse hunk headers
-		if strings.HasPrefix(line, "@@") {
+		// Parse hunk headers — the @@ line itself occupies a position.
+		if strings.HasPrefix(line, "@@") && currentFile != "" {
 			position++
-			// Extract new file start line from @@ -a,b +c,d @@
 			newLine = parseHunkNewStart(line)
 			continue
 		}
 
-		// We need a current file to map lines
 		if currentFile == "" {
 			continue
 		}
 
-		// Process diff content lines
-		if strings.HasPrefix(line, "+") {
+		// Content lines within a hunk.
+		switch {
+		case strings.HasPrefix(line, "+"):
+			// Addition: maps to both a position and a new-file line.
 			position++
 			result[currentFile][newLine] = position
 			newLine++
-		} else if strings.HasPrefix(line, "-") {
+		case strings.HasPrefix(line, "-"):
+			// Deletion: occupies a position but has no new-file line number.
 			position++
-			// Deletion lines don't map to new line numbers
-		} else if strings.HasPrefix(line, " ") {
-			// Context line (space-prefixed)
-			if position > 0 {
+		case strings.HasPrefix(line, " "):
+			// Context line: maps to both a position and a new-file line.
 			position++
 			result[currentFile][newLine] = position
 			newLine++
 		}
-		}
+		// Any other line (empty trailing lines from Split, etc.) is ignored.
 	}
 
 	return result
 }
 
 // parseHunkNewStart extracts the new-file starting line number from a hunk header.
-// Format: @@ -old_start[,old_count] +new_start[,new_count] @@
+// Format: @@ -old_start[,old_count] +new_start[,new_count] @@[ optional section heading]
 func parseHunkNewStart(hunkLine string) int {
-	// Find the +N part
+	// Find the +N part after the first @@
 	plusIdx := strings.Index(hunkLine, "+")
 	if plusIdx < 0 {
 		return 1
 	}
 	rest := hunkLine[plusIdx+1:]
 
-	// Read digits until comma or space
-	var numStr string
-	for _, ch := range rest {
-		if ch >= '0' && ch <= '9' {
-			numStr += string(ch)
-		} else {
-			break
-		}
+	// Read digits until comma, space, or end.
+	if idx := strings.IndexAny(rest, ", @"); idx > 0 {
+		rest = rest[:idx]
 	}
 
-	if numStr == "" {
+	n, err := strconv.Atoi(rest)
+	if err != nil {
 		return 1
 	}
-
-	n := 0
-	for _, ch := range numStr {
-		n = n*10 + int(ch-'0')
-	}
 	return n
 }

vcs/util_test.go

@@ -10,58 +10,59 @@ import (
 
 // mockFileReader implements vcs.FileReader for testing.
 type mockFileReader struct {
-	contents map[string][]vcs.ContentEntry // path -> entries
-	files    map[string]string             // path -> content
+	contents map[string]string             // path -> content
+	dirs     map[string][]vcs.ContentEntry // path -> entries
 }
 
-func (m *mockFileReader) GetFileContent(ctx context.Context, owner, repo, path, ref string) (string, error) {
-	content, ok := m.files[path]
+func (m *mockFileReader) GetFileContent(_ context.Context, _, _, path, _ string) (string, error) {
+	content, ok := m.contents[path]
 	if !ok {
-		return "", fmt.Errorf("HTTP 404: file not found: %s", path)
+		return "", fmt.Errorf("file not found: %s", path)
 	}
 	return content, nil
 }
 
-func (m *mockFileReader) ListContents(ctx context.Context, owner, repo, path string) ([]vcs.ContentEntry, error) {
-	entries, ok := m.contents[path]
+func (m *mockFileReader) ListContents(_ context.Context, _, _, path string) ([]vcs.ContentEntry, error) {
+	entries, ok := m.dirs[path]
 	if !ok {
-		return nil, fmt.Errorf("HTTP 404: path not found: %s", path)
+		return nil, fmt.Errorf("directory not found: %s", path)
 	}
 	return entries, nil
 }
 
-func TestGetAllFilesInPath(t *testing.T) {
-	ctx := context.Background()
+// --- GetAllFilesInPath tests ---
 
-	t.Run("empty directory", func(t *testing.T) {
-		client := &mockFileReader{
-			contents: map[string][]vcs.ContentEntry{
+func TestGetAllFilesInPath_EmptyDir(t *testing.T) {
+	mock := &mockFileReader{
+		dirs: map[string][]vcs.ContentEntry{
 			"src": {},
 		},
 	}
-		result, err := vcs.GetAllFilesInPath(ctx, client, "owner", "repo", "src")
+
+	result, err := vcs.GetAllFilesInPath(context.Background(), mock, "owner", "repo", "src")
 	if err != nil {
 		t.Fatalf("unexpected error: %v", err)
 	}
 	if len(result) != 0 {
 		t.Errorf("expected empty map, got %d entries", len(result))
 	}
-	})
+}
 
-	t.Run("flat directory", func(t *testing.T) {
-		client := &mockFileReader{
-			contents: map[string][]vcs.ContentEntry{
+func TestGetAllFilesInPath_FlatDir(t *testing.T) {
+	mock := &mockFileReader{
+		dirs: map[string][]vcs.ContentEntry{
 			"src": {
 				{Name: "main.go", Path: "src/main.go", Type: "file"},
 				{Name: "util.go", Path: "src/util.go", Type: "file"},
 			},
 		},
-			files: map[string]string{
+		contents: map[string]string{
 			"src/main.go": "package main",
-				"src/util.go": "package main\n// util",
+			"src/util.go": "package main\n\nfunc helper() {}",
 		},
 	}
-		result, err := vcs.GetAllFilesInPath(ctx, client, "owner", "repo", "src")
+
+	result, err := vcs.GetAllFilesInPath(context.Background(), mock, "owner", "repo", "src")
 	if err != nil {
 		t.Fatalf("unexpected error: %v", err)
 	}
@@ -69,35 +70,36 @@ func TestGetAllFilesInPath(t *testing.T) {
 		t.Fatalf("expected 2 files, got %d", len(result))
 	}
 	if result["src/main.go"] != "package main" {
-			t.Errorf("main.go content = %q", result["src/main.go"])
+		t.Errorf("unexpected content for main.go: %q", result["src/main.go"])
+	}
+	if result["src/util.go"] != "package main\n\nfunc helper() {}" {
+		t.Errorf("unexpected content for util.go: %q", result["src/util.go"])
 	}
-		if result["src/util.go"] != "package main\n// util" {
-			t.Errorf("util.go content = %q", result["src/util.go"])
 }
-	})
 
-	t.Run("nested directories", func(t *testing.T) {
-		client := &mockFileReader{
-			contents: map[string][]vcs.ContentEntry{
+func TestGetAllFilesInPath_NestedDirs(t *testing.T) {
+	mock := &mockFileReader{
+		dirs: map[string][]vcs.ContentEntry{
 			"src": {
 				{Name: "main.go", Path: "src/main.go", Type: "file"},
 				{Name: "pkg", Path: "src/pkg", Type: "dir"},
 			},
 			"src/pkg": {
 				{Name: "lib.go", Path: "src/pkg/lib.go", Type: "file"},
-					{Name: "sub", Path: "src/pkg/sub", Type: "dir"},
+				{Name: "internal", Path: "src/pkg/internal", Type: "dir"},
 			},
-				"src/pkg/sub": {
-					{Name: "deep.go", Path: "src/pkg/sub/deep.go", Type: "file"},
+			"src/pkg/internal": {
+				{Name: "helper.go", Path: "src/pkg/internal/helper.go", Type: "file"},
 			},
 		},
-			files: map[string]string{
+		contents: map[string]string{
 			"src/main.go":                "package main",
 			"src/pkg/lib.go":             "package pkg",
-				"src/pkg/sub/deep.go": "package sub",
+			"src/pkg/internal/helper.go": "package internal",
 		},
 	}
-		result, err := vcs.GetAllFilesInPath(ctx, client, "owner", "repo", "src")
+
+	result, err := vcs.GetAllFilesInPath(context.Background(), mock, "owner", "repo", "src")
 	if err != nil {
 		t.Fatalf("unexpected error: %v", err)
 	}
@@ -105,146 +107,350 @@ func TestGetAllFilesInPath(t *testing.T) {
 		t.Fatalf("expected 3 files, got %d", len(result))
 	}
 	if result["src/main.go"] != "package main" {
-			t.Errorf("main.go content = %q", result["src/main.go"])
+		t.Errorf("unexpected content for main.go")
 	}
 	if result["src/pkg/lib.go"] != "package pkg" {
-			t.Errorf("lib.go content = %q", result["src/pkg/lib.go"])
+		t.Errorf("unexpected content for lib.go")
+	}
+	if result["src/pkg/internal/helper.go"] != "package internal" {
+		t.Errorf("unexpected content for helper.go")
 	}
-		if result["src/pkg/sub/deep.go"] != "package sub" {
-			t.Errorf("deep.go content = %q", result["src/pkg/sub/deep.go"])
 }
-	})
 
-	t.Run("mixed files and dirs", func(t *testing.T) {
-		client := &mockFileReader{
-			contents: map[string][]vcs.ContentEntry{
+func TestGetAllFilesInPath_Mixed(t *testing.T) {
+	mock := &mockFileReader{
+		dirs: map[string][]vcs.ContentEntry{
 			"root": {
 				{Name: "README.md", Path: "root/README.md", Type: "file"},
+				{Name: "empty", Path: "root/empty", Type: "dir"},
 				{Name: "docs", Path: "root/docs", Type: "dir"},
-					{Name: "config.yaml", Path: "root/config.yaml", Type: "file"},
 			},
+			"root/empty": {},
 			"root/docs": {
 				{Name: "guide.md", Path: "root/docs/guide.md", Type: "file"},
 			},
 		},
-			files: map[string]string{
+		contents: map[string]string{
 			"root/README.md":     "# Hello",
-				"root/config.yaml":   "key: value",
 			"root/docs/guide.md": "## Guide",
 		},
 	}
-		result, err := vcs.GetAllFilesInPath(ctx, client, "owner", "repo", "root")
+
+	result, err := vcs.GetAllFilesInPath(context.Background(), mock, "owner", "repo", "root")
 	if err != nil {
 		t.Fatalf("unexpected error: %v", err)
 	}
-		if len(result) != 3 {
-			t.Fatalf("expected 3 files, got %d", len(result))
-		}
-		if result["root/README.md"] != "# Hello" {
-			t.Errorf("README content = %q", result["root/README.md"])
-		}
-		if result["root/docs/guide.md"] != "## Guide" {
-			t.Errorf("guide content = %q", result["root/docs/guide.md"])
-		}
-	})
-}
-
-func TestBuildLineToPositionMap(t *testing.T) {
-	t.Run("single hunk", func(t *testing.T) {
-		diff := "diff --git a/file.go b/file.go\nindex abc..def 100644\n--- a/file.go\n+++ b/file.go\n@@ -1,3 +1,4 @@\n package main\n \n+// new comment\n func main() {}\n"
-		result := vcs.BuildLineToPositionMap(diff)
-		fileMap, ok := result["file.go"]
-		if !ok {
-			t.Fatal("expected file.go in result")
-		}
-		// Hunk header @@ is position 1
-		// Line 1: " package main" -> position 2
-		if fileMap[1] != 2 {
-			t.Errorf("line 1 position = %d, want 2", fileMap[1])
-		}
-		// Line 2: " " (context) -> position 3
-		if fileMap[2] != 3 {
-			t.Errorf("line 2 position = %d, want 3", fileMap[2])
-		}
-		// Line 3: "+// new comment" -> position 4
-		if fileMap[3] != 4 {
-			t.Errorf("line 3 position = %d, want 4", fileMap[3])
-		}
-		// Line 4: " func main() {}" -> position 5
-		if fileMap[4] != 5 {
-			t.Errorf("line 4 position = %d, want 5", fileMap[4])
-		}
-	})
-
-	t.Run("multi hunk", func(t *testing.T) {
-		diff := "diff --git a/file.go b/file.go\n--- a/file.go\n+++ b/file.go\n@@ -1,3 +1,3 @@\n package main\n \n-// old\n+// new\n@@ -10,3 +10,4 @@\n func foo() {\n+\t// added\n \treturn\n }\n"
-		result := vcs.BuildLineToPositionMap(diff)
-		fileMap, ok := result["file.go"]
-		if !ok {
-			t.Fatal("expected file.go in result")
-		}
-		// First hunk: @@ is position 1
-		// Line 1: " package main" -> position 2
-		if fileMap[1] != 2 {
-			t.Errorf("line 1 position = %d, want 2", fileMap[1])
-		}
-		// Line 3: "+// new" -> position 5 (after " ", "-// old" at pos 3,4)
-		if fileMap[3] != 5 {
-			t.Errorf("line 3 position = %d, want 5", fileMap[3])
-		}
-		// Second hunk: @@ is position 6
-		// Line 10: " func foo() {" -> position 7
-		if fileMap[10] != 7 {
-			t.Errorf("line 10 position = %d, want 7", fileMap[10])
-		}
-		// Line 11: "+\t// added" -> position 8
-		if fileMap[11] != 8 {
-			t.Errorf("line 11 position = %d, want 8", fileMap[11])
-		}
-	})
-
-	t.Run("deletion lines not in map", func(t *testing.T) {
-		diff := "diff --git a/file.go b/file.go\n--- a/file.go\n+++ b/file.go\n@@ -1,4 +1,3 @@\n package main\n \n-// deleted line\n func main() {}\n"
-		result := vcs.BuildLineToPositionMap(diff)
-		fileMap, ok := result["file.go"]
-		if !ok {
-			t.Fatal("expected file.go in result")
-		}
-		// Line 1: " package main" -> position 2
-		if fileMap[1] != 2 {
-			t.Errorf("line 1 position = %d, want 2", fileMap[1])
-		}
-		// Line 3 in new file: " func main() {}" -> position 5 (after deletion at pos 4)
-		if fileMap[3] != 5 {
-			t.Errorf("line 3 position = %d, want 5", fileMap[3])
-		}
-		// Should only have 3 entries (lines 1, 2, 3 of new file)
-		if len(fileMap) != 3 {
-			t.Errorf("expected 3 mapped lines, got %d: %v", len(fileMap), fileMap)
-		}
-	})
-
-	t.Run("multiple files", func(t *testing.T) {
-		diff := "diff --git a/a.go b/a.go\n--- a/a.go\n+++ b/a.go\n@@ -1,2 +1,3 @@\n package a\n \n+// file a\ndiff --git a/b.go b/b.go\n--- a/b.go\n+++ b/b.go\n@@ -1,2 +1,3 @@\n package b\n \n+// file b\n"
-		result := vcs.BuildLineToPositionMap(diff)
 	if len(result) != 2 {
 		t.Fatalf("expected 2 files, got %d", len(result))
 	}
+	if result["root/README.md"] != "# Hello" {
+		t.Errorf("unexpected content for README.md")
+	}
+	if result["root/docs/guide.md"] != "## Guide" {
+		t.Errorf("unexpected content for guide.md")
+	}
+}
+
+func TestGetAllFilesInPath_ListContentsError(t *testing.T) {
+	mock := &mockFileReader{
+		dirs: map[string][]vcs.ContentEntry{},
+	}
+
+	_, err := vcs.GetAllFilesInPath(context.Background(), mock, "owner", "repo", "missing")
+	if err == nil {
+		t.Fatal("expected error for missing directory")
+	}
+}
+
+func TestGetAllFilesInPath_GetFileContentError(t *testing.T) {
+	mock := &mockFileReader{
+		dirs: map[string][]vcs.ContentEntry{
+			"src": {
+				{Name: "bad.go", Path: "src/bad.go", Type: "file"},
+			},
+		},
+		contents: map[string]string{},
+	}
+
+	_, err := vcs.GetAllFilesInPath(context.Background(), mock, "owner", "repo", "src")
+	if err == nil {
+		t.Fatal("expected error when file content fetch fails")
+	}
+}
+
+// --- BuildLineToPositionMap tests ---
+
+func TestBuildLineToPositionMap_SingleHunk(t *testing.T) {
+	diff := `diff --git a/main.go b/main.go
+index abc..def 100644
+--- a/main.go
++++ b/main.go
+@@ -5,7 +5,8 @@ package main
+ import "fmt"
+ 
+ func main() {
+-	fmt.Println("old")
++	fmt.Println("new")
++	fmt.Println("added")
+ 	return
+ }
+`
+
+	result := vcs.BuildLineToPositionMap(diff)
+
+	fileMap, ok := result["main.go"]
+	if !ok {
+		t.Fatal("expected main.go in result")
+	}
+
+	// @@ line is position 1
+	// " import \"fmt\""       -> pos 2, newLine 5
+	// " "                     -> pos 3, newLine 6
+	// " func main() {"       -> pos 4, newLine 7
+	// "-\tfmt.Println..."    -> pos 5, no new line
+	// "+\tfmt.Println..."    -> pos 6, newLine 8
+	// "+\tfmt.Println..."    -> pos 7, newLine 9
+	// " \treturn"            -> pos 8, newLine 10
+	// " }"                   -> pos 9, newLine 11
+
+	expected := map[int]int{
+		5:  2,
+		6:  3,
+		7:  4,
+		8:  6,
+		9:  7,
+		10: 8,
+		11: 9,
+	}
+
+	for line, wantPos := range expected {
+		gotPos, exists := fileMap[line]
+		if !exists {
+			t.Errorf("line %d: expected position %d, but line not in map", line, wantPos)
+			continue
+		}
+		if gotPos != wantPos {
+			t.Errorf("line %d: expected position %d, got %d", line, wantPos, gotPos)
+		}
+	}
+
+	if len(fileMap) != len(expected) {
+		t.Errorf("expected %d entries, got %d", len(expected), len(fileMap))
+	}
+}
+
+func TestBuildLineToPositionMap_MultiHunk(t *testing.T) {
+	diff := `diff --git a/main.go b/main.go
+--- a/main.go
++++ b/main.go
+@@ -1,3 +1,4 @@
+ package main
+ 
++import "fmt"
+ func main() {
+@@ -10,3 +11,4 @@ func main() {
+ 	return
++	// extra
+ }
+`
+
+	result := vcs.BuildLineToPositionMap(diff)
+
+	fileMap, ok := result["main.go"]
+	if !ok {
+		t.Fatal("expected main.go in result")
+	}
+
+	// First hunk:
+	// @@ line         -> pos 1
+	// " package main" -> pos 2, newLine 1
+	// " "             -> pos 3, newLine 2
+	// "+import..."    -> pos 4, newLine 3
+	// " func main.."  -> pos 5, newLine 4
+	//
+	// Second hunk (position continues!):
+	// @@ line         -> pos 6
+	// " \treturn"     -> pos 7, newLine 11
+	// "+\t// extra"   -> pos 8, newLine 12
+	// " }"            -> pos 9, newLine 13
+
+	expected := map[int]int{
+		1:  2,
+		2:  3,
+		3:  4,
+		4:  5,
+		11: 7,
+		12: 8,
+		13: 9,
+	}
+
+	for line, wantPos := range expected {
+		gotPos, exists := fileMap[line]
+		if !exists {
+			t.Errorf("line %d: expected position %d, but line not in map", line, wantPos)
+			continue
+		}
+		if gotPos != wantPos {
+			t.Errorf("line %d: expected position %d, got %d", line, wantPos, gotPos)
+		}
+	}
+}
+
+func TestBuildLineToPositionMap_DeletionLinesNotInMap(t *testing.T) {
+	diff := `diff --git a/old.go b/old.go
+--- a/old.go
++++ b/old.go
+@@ -1,3 +1,1 @@
+-line one
+-line two
+ remaining
+`
+
+	result := vcs.BuildLineToPositionMap(diff)
+
+	fileMap, ok := result["old.go"]
+	if !ok {
+		t.Fatal("expected old.go in result")
+	}
+
+	// @@ line        -> pos 1
+	// "-line one"    -> pos 2, no new line
+	// "-line two"    -> pos 3, no new line
+	// " remaining"   -> pos 4, newLine 1
+
+	if pos, ok := fileMap[1]; !ok || pos != 4 {
+		t.Errorf("line 1: expected position 4, got %d (exists=%v)", pos, ok)
+	}
+	if len(fileMap) != 1 {
+		t.Errorf("expected 1 entry (only 'remaining'), got %d", len(fileMap))
+	}
+}
+
+func TestBuildLineToPositionMap_MultipleFiles(t *testing.T) {
+	diff := `diff --git a/a.go b/a.go
+--- a/a.go
++++ b/a.go
+@@ -1,2 +1,3 @@
+ package a
++// added
+ 
+diff --git a/b.go b/b.go
+new file mode 100644
+--- /dev/null
++++ b/b.go
+@@ -0,0 +1,3 @@
++package b
++
++func B() {}
+`
+
+	result := vcs.BuildLineToPositionMap(diff)
+
+	// File a.go
 	aMap, ok := result["a.go"]
 	if !ok {
 		t.Fatal("expected a.go in result")
 	}
+	// @@ line      -> pos 1
+	// " package a" -> pos 2, newLine 1
+	// "+// added"  -> pos 3, newLine 2
+	// " "          -> pos 4, newLine 3
+	if aMap[1] != 2 {
+		t.Errorf("a.go line 1: expected pos 2, got %d", aMap[1])
+	}
+	if aMap[2] != 3 {
+		t.Errorf("a.go line 2: expected pos 3, got %d", aMap[2])
+	}
+	if aMap[3] != 4 {
+		t.Errorf("a.go line 3: expected pos 4, got %d", aMap[3])
+	}
+
+	// File b.go — position resets for new file
 	bMap, ok := result["b.go"]
 	if !ok {
 		t.Fatal("expected b.go in result")
 	}
-		// a.go line 3: "+// file a" -> position 4
-		if aMap[3] != 4 {
-			t.Errorf("a.go line 3 position = %d, want 4", aMap[3])
+	// @@ line          -> pos 1
+	// "+package b"     -> pos 2, newLine 1
+	// "+"              -> pos 3, newLine 2
+	// "+func B() {}"   -> pos 4, newLine 3
+	if bMap[1] != 2 {
+		t.Errorf("b.go line 1: expected pos 2, got %d", bMap[1])
+	}
+	if bMap[2] != 3 {
+		t.Errorf("b.go line 2: expected pos 3, got %d", bMap[2])
 	}
-		// b.go line 3: "+// file b" -> position 4
 	if bMap[3] != 4 {
-			t.Errorf("b.go line 3 position = %d, want 4", bMap[3])
+		t.Errorf("b.go line 3: expected pos 4, got %d", bMap[3])
+	}
+}
+
+func TestBuildLineToPositionMap_EmptyDiff(t *testing.T) {
+	result := vcs.BuildLineToPositionMap("")
+	if len(result) != 0 {
+		t.Errorf("expected empty map for empty diff, got %d entries", len(result))
+	}
+}
+
+func TestBuildLineToPositionMap_NoNewlineMarker(t *testing.T) {
+	diff := `diff --git a/a.go b/a.go
+--- a/a.go
++++ b/a.go
+@@ -1,2 +1,2 @@
+-old
++new
+\ No newline at end of file
+`
+
+	result := vcs.BuildLineToPositionMap(diff)
+
+	fileMap := result["a.go"]
+	// @@ line  -> pos 1
+	// "-old"   -> pos 2
+	// "+new"   -> pos 3, newLine 1
+	// "\ No.." -> not counted
+	if fileMap[1] != 3 {
+		t.Errorf("line 1: expected position 3, got %d", fileMap[1])
+	}
+	if len(fileMap) != 1 {
+		t.Errorf("expected 1 entry, got %d", len(fileMap))
+	}
+}
+
+func TestBuildLineToPositionMap_SingleLineHunk(t *testing.T) {
+	diff := `diff --git a/single.go b/single.go
+--- a/single.go
++++ b/single.go
+@@ -1 +1 @@
+-old
++new
+`
+
+	result := vcs.BuildLineToPositionMap(diff)
+
+	fileMap := result["single.go"]
+	// @@ line -> pos 1
+	// "-old"  -> pos 2
+	// "+new"  -> pos 3, newLine 1
+	if fileMap[1] != 3 {
+		t.Errorf("line 1: expected position 3, got %d", fileMap[1])
+	}
+}
+
+func TestBuildLineToPositionMap_DeletedFile(t *testing.T) {
+	diff := `diff --git a/deleted.go b/deleted.go
+deleted file mode 100644
+--- a/deleted.go
++++ /dev/null
+@@ -1,3 +0,0 @@
+-package deleted
+-
+-func Gone() {}
+`
+
+	result := vcs.BuildLineToPositionMap(diff)
+
+	if _, ok := result["deleted.go"]; ok {
+		t.Error("deleted file should not appear in result")
 	}
-	})
 }