From 7c83365fc46f872058c97b98354232c51473656c Mon Sep 17 00:00:00 2001
From: claw <claw@weiker.me>
Date: Tue, 12 May 2026 12:38:21 -0700
Subject: [PATCH 1/3] =?UTF-8?q?feat(vcs):=20complete=20Phase=201=20?=
 =?UTF-8?q?=E2=80=94=20util.go,=20type=20cleanup,=20interface=20additions?=
 =?UTF-8?q?=20(fixes=20#84,=20#85,=20#86)?=
MIME-Version: 1.0
Content-Type: text/plain; charset=UTF-8
Content-Transfer-Encoding: 8bit

- Create vcs/util.go with GetAllFilesInPath and BuildLineToPositionMap
- Create vcs/util_test.go with comprehensive tests for both functions
- Remove review.ContentEntry type, replace with vcs.ContentEntry
- Remove review.GiteaClient interface, replace with vcs.FileReader
- Update review/repo_persona.go to use vcs.FileReader
- Update review/repo_persona_test.go to use vcs.ContentEntry
- Update cmd/review-bot/main.go adapter to implement vcs.FileReader
- Add Number and Base fields to vcs.PullRequest
- Add CommitStatus type to vcs/types.go
- Add GetFileContentAtRef to vcs.PRReader interface
- Add GetCommitStatuses to vcs.PRReader interface
- Add DismissReview to vcs.Reviewer interface
- Add stub implementations on gitea.Client for new interface methods

Closes #84, Closes #85, Closes #86
---
 cmd/review-bot/main.go      |  14 +-
 gitea/client.go             |  12 ++
 review/repo_persona.go      |  21 +--
 review/repo_persona_test.go |  93 +++++---------
 vcs/interfaces.go           |   3 +
 vcs/types.go                |  21 ++-
 vcs/util.go                 | 145 +++++++++++++++++++++
 vcs/util_test.go            | 250 ++++++++++++++++++++++++++++++++++++
 8 files changed, 472 insertions(+), 87 deletions(-)
 create mode 100644 vcs/util.go
 create mode 100644 vcs/util_test.go

diff --git a/cmd/review-bot/main.go b/cmd/review-bot/main.go
index cc6381a..44f1306 100644
--- a/cmd/review-bot/main.go
+++ b/cmd/review-bot/main.go
@@ -15,6 +15,7 @@ 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"
@@ -812,7 +813,7 @@ func shouldSkipStaleReview(evaluatedSHA, currentSHA string) bool {
 	return evaluatedSHA != currentSHA
 }
 
-// giteaClientAdapter adapts gitea.Client to review.GiteaClient interface.
+// giteaClientAdapter adapts gitea.Client to vcs.FileReader interface.
 type giteaClientAdapter struct {
 	client *gitea.Client
 }
@@ -821,14 +822,14 @@ func newGiteaClientAdapter(c *gitea.Client) *giteaClientAdapter {
 	return &giteaClientAdapter{client: c}
 }
 
-func (a *giteaClientAdapter) ListContents(ctx context.Context, owner, repo, path string) ([]review.ContentEntry, error) {
+func (a *giteaClientAdapter) ListContents(ctx context.Context, owner, repo, path string) ([]vcs.ContentEntry, error) {
 	entries, err := a.client.ListContents(ctx, owner, repo, path)
 	if err != nil {
 		return nil, err
 	}
-	result := make([]review.ContentEntry, len(entries))
+	result := make([]vcs.ContentEntry, len(entries))
 	for i, e := range entries {
-		result[i] = review.ContentEntry{
+		result[i] = vcs.ContentEntry{
 			Name: e.Name,
 			Path: e.Path,
 			Type: e.Type,
@@ -837,6 +838,9 @@ func (a *giteaClientAdapter) ListContents(ctx context.Context, owner, repo, path
 	return result, nil
 }
 
-func (a *giteaClientAdapter) GetFileContent(ctx context.Context, owner, repo, filepath string) (string, error) {
+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)
+	}
 	return a.client.GetFileContent(ctx, owner, repo, filepath)
 }
diff --git a/gitea/client.go b/gitea/client.go
index 55835ac..74fce56 100644
--- a/gitea/client.go
+++ b/gitea/client.go
@@ -831,3 +831,15 @@ 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)
+}
diff --git a/review/repo_persona.go b/review/repo_persona.go
index 58c0b9d..5b0fe6e 100644
--- a/review/repo_persona.go
+++ b/review/repo_persona.go
@@ -4,32 +4,19 @@ 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 GiteaClient, owner, repo string) (map[string]*Persona, error) {
+func LoadRepoPersonas(ctx context.Context, client vcs.FileReader, owner, repo string) (map[string]*Persona, error) {
 	result := make(map[string]*Persona)
 
 	entries, err := client.ListContents(ctx, owner, repo, RepoPersonaPath)
@@ -57,7 +44,7 @@ func LoadRepoPersonas(ctx context.Context, client GiteaClient, owner, repo strin
 			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,
diff --git a/review/repo_persona_test.go b/review/repo_persona_test.go
index 56b0a59..43652b5 100644
--- a/review/repo_persona_test.go
+++ b/review/repo_persona_test.go
@@ -5,23 +5,21 @@ import (
 	"errors"
 	"strings"
 	"testing"
+
+	"gitea.weiker.me/rodin/review-bot/vcs"
 )
 
 func TestParsePersonaBytes(t *testing.T) {
 	tests := []struct {
-		name       string
-		data       string
-		source     string
-		wantName   string
-		wantErr    string
+		name     string
+		data     string
+		source   string
+		wantName string
+		wantErr  string
 	}{
 		{
 			name: "valid yaml",
-			data: `name: test
-identity: test identity
-focus:
-  - testing
-`,
+			data: "name: test\nidentity: test identity\nfocus:\n  - testing\n",
 			source:   "test.yaml",
 			wantName: "test",
 		},
@@ -38,8 +36,8 @@ focus:
 			wantErr: "parse",
 		},
 		{
-			name: "json format by extension",
-			data: `{"name": "jsontest", "identity": "json identity"}`,
+			name:     "json format by extension",
+			data:     `{"name": "jsontest", "identity": "json identity"}`,
 			source:   "test.json",
 			wantName: "jsontest",
 		},
@@ -67,15 +65,15 @@ focus:
 	}
 }
 
-// mockGiteaClient implements GiteaClient for testing.
+// mockGiteaClient implements vcs.FileReader for testing.
 type mockGiteaClient struct {
-	contents map[string][]ContentEntry // path -> entries
-	files    map[string]string         // path -> content
+	contents map[string][]vcs.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) ([]ContentEntry, error) {
+func (m *mockGiteaClient) ListContents(ctx context.Context, owner, repo, path string) ([]vcs.ContentEntry, error) {
 	if m.listErr != nil {
 		return nil, m.listErr
 	}
@@ -86,7 +84,7 @@ func (m *mockGiteaClient) ListContents(ctx context.Context, owner, repo, path st
 	return entries, nil
 }
 
-func (m *mockGiteaClient) GetFileContent(ctx context.Context, owner, repo, filepath string) (string, error) {
+func (m *mockGiteaClient) GetFileContent(ctx context.Context, owner, repo, filepath, ref string) (string, error) {
 	if m.fileErr != nil {
 		if err, ok := m.fileErr[filepath]; ok {
 			return "", err
@@ -118,7 +116,7 @@ func TestLoadRepoPersonas(t *testing.T) {
 
 	t.Run("empty directory returns empty map", func(t *testing.T) {
 		client := &mockGiteaClient{
-			contents: map[string][]ContentEntry{
+			contents: map[string][]vcs.ContentEntry{
 				RepoPersonaPath: {},
 			},
 		}
@@ -133,27 +131,15 @@ func TestLoadRepoPersonas(t *testing.T) {
 
 	t.Run("loads valid personas", func(t *testing.T) {
 		client := &mockGiteaClient{
-			contents: map[string][]ContentEntry{
+			contents: map[string][]vcs.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
-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
-`,
+				".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",
 			},
 		}
 		personas, err := LoadRepoPersonas(ctx, client, "owner", "repo")
@@ -176,16 +162,14 @@ focus:
 
 	t.Run("skips invalid persona files", func(t *testing.T) {
 		client := &mockGiteaClient{
-			contents: map[string][]ContentEntry{
+			contents: map[string][]vcs.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
-identity: Valid persona
-`,
+				".review-bot/personas/valid.yaml":   "name: valid\nidentity: Valid persona\n",
 				".review-bot/personas/invalid.yaml": "not valid yaml: [broken",
 			},
 		}
@@ -193,7 +177,6 @@ identity: Valid persona
 		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))
 		}
@@ -204,7 +187,7 @@ identity: Valid persona
 
 	t.Run("skips non-yaml files", func(t *testing.T) {
 		client := &mockGiteaClient{
-			contents: map[string][]ContentEntry{
+			contents: map[string][]vcs.ContentEntry{
 				RepoPersonaPath: {
 					{Name: "persona.yaml", Path: ".review-bot/personas/persona.yaml", Type: "file"},
 					{Name: "README.md", Path: ".review-bot/personas/README.md", Type: "file"},
@@ -212,10 +195,8 @@ identity: Valid persona
 				},
 			},
 			files: map[string]string{
-				".review-bot/personas/persona.yaml": `name: test
-identity: Test persona
-`,
-				".review-bot/personas/README.md": "# Personas\n\nPut your personas here.",
+				".review-bot/personas/persona.yaml": "name: test\nidentity: Test persona\n",
+				".review-bot/personas/README.md":    "# Personas\n\nPut your personas here.",
 			},
 		}
 		personas, err := LoadRepoPersonas(ctx, client, "owner", "repo")
@@ -229,16 +210,14 @@ identity: Test persona
 
 	t.Run("skips subdirectories", func(t *testing.T) {
 		client := &mockGiteaClient{
-			contents: map[string][]ContentEntry{
+			contents: map[string][]vcs.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
-identity: Test persona
-`,
+				".review-bot/personas/persona.yaml": "name: test\nidentity: Test persona\n",
 			},
 		}
 		personas, err := LoadRepoPersonas(ctx, client, "owner", "repo")
@@ -265,16 +244,14 @@ identity: Test persona
 
 	t.Run("skips files that fail to fetch", func(t *testing.T) {
 		client := &mockGiteaClient{
-			contents: map[string][]ContentEntry{
+			contents: map[string][]vcs.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
-identity: Good persona
-`,
+				".review-bot/personas/good.yaml": "name: good\nidentity: Good persona\n",
 			},
 			fileErr: map[string]error{
 				".review-bot/personas/bad.yaml": errors.New("HTTP 500: internal server error"),
@@ -290,27 +267,23 @@ identity: Good persona
 	})
 
 	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][]ContentEntry{
+			contents: map[string][]vcs.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
-identity: Normal sized persona
-`,
-				".review-bot/personas/huge.yaml": oversizedContent,
+				".review-bot/personas/normal.yaml": "name: normal\nidentity: Normal sized persona\n",
+				".review-bot/personas/huge.yaml":   oversizedContent,
 			},
 		}
 		personas, err := LoadRepoPersonas(ctx, client, "owner", "repo")
 		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))
 		}
@@ -370,7 +343,6 @@ 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 {
@@ -378,7 +350,6 @@ 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)
@@ -422,8 +393,6 @@ 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},
diff --git a/vcs/interfaces.go b/vcs/interfaces.go
index ecada13..3bc299e 100644
--- a/vcs/interfaces.go
+++ b/vcs/interfaces.go
@@ -10,6 +10,8 @@ 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.
@@ -23,6 +25,7 @@ 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.
diff --git a/vcs/types.go b/vcs/types.go
index 6dfd932..de904f3 100644
--- a/vcs/types.go
+++ b/vcs/types.go
@@ -15,6 +15,11 @@ 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"`
@@ -28,9 +33,11 @@ type UserInfo struct {
 
 // PullRequest holds relevant PR metadata.
 type PullRequest struct {
-	Title string  `json:"title"`
-	Body  string  `json:"body"`
-	Head  HeadRef `json:"head"`
+	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.
@@ -46,6 +53,14 @@ 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"`
diff --git a/vcs/util.go b/vcs/util.go
new file mode 100644
index 0000000..9f133fd
--- /dev/null
+++ b/vcs/util.go
@@ -0,0 +1,145 @@
+package vcs
+
+import (
+	"context"
+	"fmt"
+	"strings"
+)
+
+// GetAllFilesInPath recursively fetches all file contents under a path using the
+// provided FileReader. Returns a map of filepath -> content for all files found.
+// If the path points to an empty directory, returns an empty map.
+func GetAllFilesInPath(ctx context.Context, client FileReader, owner, repo, path string) (map[string]string, error) {
+	results := make(map[string]string)
+
+	entries, err := client.ListContents(ctx, owner, repo, path)
+	if err != nil {
+		return nil, fmt.Errorf("list contents %q: %w", path, err)
+	}
+
+	for _, entry := range entries {
+		switch entry.Type {
+		case "file":
+			content, err := client.GetFileContent(ctx, owner, repo, entry.Path, "")
+			if err != nil {
+				return nil, fmt.Errorf("get file %q: %w", entry.Path, err)
+			}
+			results[entry.Path] = content
+		case "dir":
+			subResults, err := GetAllFilesInPath(ctx, client, owner, repo, entry.Path)
+			if err != nil {
+				return nil, fmt.Errorf("recurse into %q: %w", entry.Path, err)
+			}
+			for k, v := range subResults {
+				results[k] = v
+			}
+		}
+	}
+
+	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.
+func BuildLineToPositionMap(diff string) map[string]map[int]int {
+	result := make(map[string]map[int]int)
+
+	lines := strings.Split(diff, "\n")
+	var currentFile string
+	var position int
+	var newLine int
+
+	for _, line := range lines {
+		// Detect new file in diff
+		if strings.HasPrefix(line, "+++ b/") {
+			currentFile = strings.TrimPrefix(line, "+++ b/")
+			position = 0
+			newLine = 0
+			if result[currentFile] == nil {
+				result[currentFile] = make(map[int]int)
+			}
+			continue
+		}
+
+		// Skip --- lines (old file header)
+		if strings.HasPrefix(line, "--- ") {
+			continue
+		}
+
+		// Skip diff --git lines
+		if strings.HasPrefix(line, "diff --git") {
+			continue
+		}
+
+		// Skip index lines
+		if strings.HasPrefix(line, "index ") {
+			continue
+		}
+
+		// Parse hunk headers
+		if strings.HasPrefix(line, "@@") {
+			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, "+") {
+			position++
+			result[currentFile][newLine] = position
+			newLine++
+		} else if strings.HasPrefix(line, "-") {
+			position++
+			// Deletion lines don't map to new line numbers
+		} else if strings.HasPrefix(line, " ") {
+			// Context line (space-prefixed)
+			if position > 0 {
+				position++
+				result[currentFile][newLine] = position
+				newLine++
+			}
+		}
+	}
+
+	return result
+}
+
+// parseHunkNewStart extracts the new-file starting line number from a hunk header.
+// Format: @@ -old_start[,old_count] +new_start[,new_count] @@
+func parseHunkNewStart(hunkLine string) int {
+	// Find the +N part
+	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
+		}
+	}
+
+	if numStr == "" {
+		return 1
+	}
+
+	n := 0
+	for _, ch := range numStr {
+		n = n*10 + int(ch-'0')
+	}
+	return n
+}
diff --git a/vcs/util_test.go b/vcs/util_test.go
new file mode 100644
index 0000000..acdac7f
--- /dev/null
+++ b/vcs/util_test.go
@@ -0,0 +1,250 @@
+package vcs_test
+
+import (
+	"context"
+	"fmt"
+	"testing"
+
+	"gitea.weiker.me/rodin/review-bot/vcs"
+)
+
+// mockFileReader implements vcs.FileReader for testing.
+type mockFileReader struct {
+	contents map[string][]vcs.ContentEntry // path -> entries
+	files    map[string]string             // path -> content
+}
+
+func (m *mockFileReader) GetFileContent(ctx context.Context, owner, repo, path, ref string) (string, error) {
+	content, ok := m.files[path]
+	if !ok {
+		return "", fmt.Errorf("HTTP 404: 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]
+	if !ok {
+		return nil, fmt.Errorf("HTTP 404: path not found: %s", path)
+	}
+	return entries, nil
+}
+
+func TestGetAllFilesInPath(t *testing.T) {
+	ctx := context.Background()
+
+	t.Run("empty directory", func(t *testing.T) {
+		client := &mockFileReader{
+			contents: map[string][]vcs.ContentEntry{
+				"src": {},
+			},
+		}
+		result, err := vcs.GetAllFilesInPath(ctx, client, "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{
+				"src": {
+					{Name: "main.go", Path: "src/main.go", Type: "file"},
+					{Name: "util.go", Path: "src/util.go", Type: "file"},
+				},
+			},
+			files: map[string]string{
+				"src/main.go": "package main",
+				"src/util.go": "package main\n// util",
+			},
+		}
+		result, err := vcs.GetAllFilesInPath(ctx, client, "owner", "repo", "src")
+		if err != nil {
+			t.Fatalf("unexpected error: %v", err)
+		}
+		if len(result) != 2 {
+			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"])
+		}
+		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{
+				"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"},
+				},
+				"src/pkg/sub": {
+					{Name: "deep.go", Path: "src/pkg/sub/deep.go", Type: "file"},
+				},
+			},
+			files: map[string]string{
+				"src/main.go":         "package main",
+				"src/pkg/lib.go":      "package pkg",
+				"src/pkg/sub/deep.go": "package sub",
+			},
+		}
+		result, err := vcs.GetAllFilesInPath(ctx, client, "owner", "repo", "src")
+		if err != nil {
+			t.Fatalf("unexpected error: %v", err)
+		}
+		if len(result) != 3 {
+			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"])
+		}
+		if result["src/pkg/lib.go"] != "package pkg" {
+			t.Errorf("lib.go content = %q", result["src/pkg/lib.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{
+				"root": {
+					{Name: "README.md", Path: "root/README.md", Type: "file"},
+					{Name: "docs", Path: "root/docs", Type: "dir"},
+					{Name: "config.yaml", Path: "root/config.yaml", Type: "file"},
+				},
+				"root/docs": {
+					{Name: "guide.md", Path: "root/docs/guide.md", Type: "file"},
+				},
+			},
+			files: 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")
+		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))
+		}
+		aMap, ok := result["a.go"]
+		if !ok {
+			t.Fatal("expected a.go in result")
+		}
+		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])
+		}
+		// b.go line 3: "+// file b" -> position 4
+		if bMap[3] != 4 {
+			t.Errorf("b.go line 3 position = %d, want 4", bMap[3])
+		}
+	})
+}
-- 
2.47.3


From 1749d95727f84d0228ca72ab9b8decf349f4b795 Mon Sep 17 00:00:00 2001
From: claw <claw@weiker.me>
Date: Tue, 12 May 2026 12:56:13 -0700
Subject: [PATCH 2/3] fix(vcs): address review findings on PR #88
MIME-Version: 1.0
Content-Type: text/plain; charset=UTF-8
Content-Transfer-Encoding: 8bit

Findings addressed:
- F1/G1: Add doc comment to GetAllFilesInPath documenting fail-fast contract
- F2/G2: Add explicit backslash-prefix guard to skip '\ No newline' markers
- F3: Add comment explaining position > 0 guard (skip lines before first hunk)
- F4: Refactor parseHunkNewStart to use strconv.Atoi instead of per-char concat
- F5: Add error propagation tests (ListContents, GetFileContent, nested, ctx cancel)
- F6: Wrap errors.ErrUnsupported in DismissReview for programmatic checking
- S1: Add ctx.Err() checks + max file count/byte constants with clear errors
- S2: Addressed by S1 — input bounds are now enforced via the same constants
---
 gitea/client.go  |   2 +-
 vcs/util.go      | 110 ++++++++++++++++++++++++++++++++++-------------
 vcs/util_test.go |  81 ++++++++++++++++++++++++++++++++++
 3 files changed, 161 insertions(+), 32 deletions(-)

diff --git a/gitea/client.go b/gitea/client.go
index 74fce56..ab963a6 100644
--- a/gitea/client.go
+++ b/gitea/client.go
@@ -835,7 +835,7 @@ func (c *Client) ResolveComment(ctx context.Context, owner, repo string, comment
 // 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")
+	return fmt.Errorf("DismissReview: %w", errors.ErrUnsupported)
 }
 
 // GetFileContentAtRef fetches a file at a specific ref from a repo.
diff --git a/vcs/util.go b/vcs/util.go
index 9f133fd..f1266c8 100644
--- a/vcs/util.go
+++ b/vcs/util.go
@@ -3,39 +3,82 @@ package vcs
 import (
 	"context"
 	"fmt"
+	"strconv"
 	"strings"
 )
 
+const (
+	// maxFilesInPath is the maximum number of files GetAllFilesInPath will fetch.
+	// Prevents unbounded resource consumption on very large directory trees.
+	maxFilesInPath = 10000
+
+	// maxTotalBytesInPath is the maximum total bytes GetAllFilesInPath will accumulate.
+	// Prevents memory exhaustion when fetching large repositories.
+	maxTotalBytesInPath = 100 * 1024 * 1024 // 100 MB
+)
+
 // GetAllFilesInPath recursively fetches all file contents under a path using the
 // provided FileReader. Returns a map of filepath -> content for all files found.
 // If the path points to an empty directory, returns an empty map.
+//
+// This function uses fail-fast error handling: any error from ListContents or
+// GetFileContent aborts the entire traversal and returns the error immediately.
+// This differs from gitea.Client.GetAllFilesInPath, which logs errors and continues.
+// The fail-fast contract ensures callers can trust that a nil error means all files
+// were successfully fetched.
+//
+// Resource limits: the traversal is bounded by maxFilesInPath (file count) and
+// maxTotalBytesInPath (total accumulated bytes). The context is checked before each
+// recursive call and file fetch to respect cancellation.
 func GetAllFilesInPath(ctx context.Context, client FileReader, owner, repo, path string) (map[string]string, error) {
 	results := make(map[string]string)
+	totalBytes := 0
 
-	entries, err := client.ListContents(ctx, owner, repo, path)
-	if err != nil {
-		return nil, fmt.Errorf("list contents %q: %w", path, err)
-	}
+	var walk func(string) error
+	walk = func(dir string) error {
+		if err := ctx.Err(); err != nil {
+			return fmt.Errorf("context cancelled during traversal: %w", err)
+		}
 
-	for _, entry := range entries {
-		switch entry.Type {
-		case "file":
-			content, err := client.GetFileContent(ctx, owner, repo, entry.Path, "")
-			if err != nil {
-				return nil, fmt.Errorf("get file %q: %w", entry.Path, err)
+		entries, err := client.ListContents(ctx, owner, repo, dir)
+		if err != nil {
+			return fmt.Errorf("list contents %q: %w", dir, err)
+		}
+
+		for _, entry := range entries {
+			if err := ctx.Err(); err != nil {
+				return fmt.Errorf("context cancelled during traversal: %w", err)
 			}
-			results[entry.Path] = content
-		case "dir":
-			subResults, err := GetAllFilesInPath(ctx, client, owner, repo, entry.Path)
-			if err != nil {
-				return nil, fmt.Errorf("recurse into %q: %w", entry.Path, err)
-			}
-			for k, v := range subResults {
-				results[k] = v
+
+			switch entry.Type {
+			case "file":
+				if len(results) >= maxFilesInPath {
+					return fmt.Errorf("exceeded max file count (%d) in path %q", maxFilesInPath, path)
+				}
+
+				content, err := client.GetFileContent(ctx, owner, repo, entry.Path, "")
+				if err != nil {
+					return fmt.Errorf("get file %q: %w", entry.Path, err)
+				}
+
+				totalBytes += len(content)
+				if totalBytes > maxTotalBytesInPath {
+					return fmt.Errorf("exceeded max total bytes (%d) in path %q", maxTotalBytesInPath, path)
+				}
+
+				results[entry.Path] = content
+			case "dir":
+				if err := walk(entry.Path); err != nil {
+					return err
+				}
 			}
 		}
+		return nil
 	}
 
+	if err := walk(path); err != nil {
+		return nil, err
+	}
 	return results, nil
 }
 
@@ -92,6 +135,12 @@ func BuildLineToPositionMap(diff string) map[string]map[int]int {
 			continue
 		}
 
+		// Skip "\ No newline at end of file" markers — these are git diff
+		// metadata and not part of the file content.
+		if strings.HasPrefix(line, `\`) {
+			continue
+		}
+
 		// Process diff content lines
 		if strings.HasPrefix(line, "+") {
 			position++
@@ -101,7 +150,10 @@ func BuildLineToPositionMap(diff string) map[string]map[int]int {
 			position++
 			// Deletion lines don't map to new line numbers
 		} else if strings.HasPrefix(line, " ") {
-			// Context line (space-prefixed)
+			// Context line (space-prefixed).
+			// Only map if position > 0, which means we've seen a hunk header.
+			// Lines before the first hunk header (position == 0) are not part
+			// of any diff hunk and should be skipped.
 			if position > 0 {
 				position++
 				result[currentFile][newLine] = position
@@ -123,23 +175,19 @@ func parseHunkNewStart(hunkLine string) int {
 	}
 	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
-		}
+	// Find the end of the number (first non-digit after +)
+	endIdx := 0
+	for endIdx < len(rest) && rest[endIdx] >= '0' && rest[endIdx] <= '9' {
+		endIdx++
 	}
 
-	if numStr == "" {
+	if endIdx == 0 {
 		return 1
 	}
 
-	n := 0
-	for _, ch := range numStr {
-		n = n*10 + int(ch-'0')
+	n, err := strconv.Atoi(rest[:endIdx])
+	if err != nil {
+		return 1
 	}
 	return n
 }
diff --git a/vcs/util_test.go b/vcs/util_test.go
index acdac7f..8436884 100644
--- a/vcs/util_test.go
+++ b/vcs/util_test.go
@@ -2,6 +2,7 @@ package vcs_test
 
 import (
 	"context"
+	"strings"
 	"fmt"
 	"testing"
 
@@ -248,3 +249,83 @@ func TestBuildLineToPositionMap(t *testing.T) {
 		}
 	})
 }
+
+func TestGetAllFilesInPath_ErrorPropagation(t *testing.T) {
+	ctx := context.Background()
+
+	t.Run("ListContents error propagates", func(t *testing.T) {
+		client := &mockFileReader{
+			contents: map[string][]vcs.ContentEntry{
+				// "src" not in map, so ListContents will fail
+			},
+		}
+		_, err := vcs.GetAllFilesInPath(ctx, client, "owner", "repo", "src")
+		if err == nil {
+			t.Fatal("expected error, got nil")
+		}
+		if !strings.Contains(err.Error(), "list contents") {
+			t.Errorf("expected error about list contents, got: %v", err)
+		}
+	})
+
+	t.Run("GetFileContent error propagates", func(t *testing.T) {
+		client := &mockFileReader{
+			contents: map[string][]vcs.ContentEntry{
+				"src": {
+					{Name: "main.go", Path: "src/main.go", Type: "file"},
+				},
+			},
+			files: map[string]string{
+				// "src/main.go" not in files map, so GetFileContent will fail
+			},
+		}
+		_, err := vcs.GetAllFilesInPath(ctx, client, "owner", "repo", "src")
+		if err == nil {
+			t.Fatal("expected error, got nil")
+		}
+		if !strings.Contains(err.Error(), "get file") {
+			t.Errorf("expected error about get file, got: %v", err)
+		}
+	})
+
+	t.Run("nested ListContents error propagates", func(t *testing.T) {
+		client := &mockFileReader{
+			contents: map[string][]vcs.ContentEntry{
+				"src": {
+					{Name: "pkg", Path: "src/pkg", Type: "dir"},
+				},
+				// "src/pkg" not in map, so recursive ListContents will fail
+			},
+		}
+		_, err := vcs.GetAllFilesInPath(ctx, client, "owner", "repo", "src")
+		if err == nil {
+			t.Fatal("expected error, got nil")
+		}
+		if !strings.Contains(err.Error(), "list contents") {
+			t.Errorf("expected error about list contents, got: %v", err)
+		}
+	})
+
+	t.Run("cancelled context propagates", func(t *testing.T) {
+		ctx, cancel := context.WithCancel(context.Background())
+		cancel() // Cancel immediately
+
+		client := &mockFileReader{
+			contents: map[string][]vcs.ContentEntry{
+				"src": {
+					{Name: "main.go", Path: "src/main.go", Type: "file"},
+				},
+			},
+			files: map[string]string{
+				"src/main.go": "package main",
+			},
+		}
+		_, err := vcs.GetAllFilesInPath(ctx, client, "owner", "repo", "src")
+		if err == nil {
+			t.Fatal("expected error from cancelled context, got nil")
+		}
+		if !strings.Contains(err.Error(), "context cancelled") {
+			t.Errorf("expected context cancellation error, got: %v", err)
+		}
+	})
+}
-- 
2.47.3


From ec03dc2373b049889e3d09f29ac104fbaa6bc2b4 Mon Sep 17 00:00:00 2001
From: claw <claw@weiker.me>
Date: Tue, 12 May 2026 13:07:41 -0700
Subject: [PATCH 3/3] fix: address remaining review findings (interface
 assertions, DismissReview ctx, import order, filepath param, spelling)

---
 cmd/review-bot/main.go    |  6 +++---
 gitea/client.go           |  2 +-
 gitea/conformance_test.go | 25 +++++++++++++++++++++++++
 vcs/util.go               |  4 ++--
 vcs/util_test.go          |  8 ++++----
 5 files changed, 35 insertions(+), 10 deletions(-)
 create mode 100644 gitea/conformance_test.go

diff --git a/cmd/review-bot/main.go b/cmd/review-bot/main.go
index 44f1306..40efc46 100644
--- a/cmd/review-bot/main.go
+++ b/cmd/review-bot/main.go
@@ -838,9 +838,9 @@ 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) {
+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)
+		return a.client.GetFileContentRef(ctx, owner, repo, filePath, ref)
 	}
-	return a.client.GetFileContent(ctx, owner, repo, filepath)
+	return a.client.GetFileContent(ctx, owner, repo, filePath)
 }
diff --git a/gitea/client.go b/gitea/client.go
index ab963a6..3284314 100644
--- a/gitea/client.go
+++ b/gitea/client.go
@@ -835,7 +835,7 @@ func (c *Client) ResolveComment(ctx context.Context, owner, repo string, comment
 // 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: %w", errors.ErrUnsupported)
+	return fmt.Errorf("dismiss review %d on %s/%s#%d: %w", reviewID, owner, repo, number, errors.ErrUnsupported)
 }
 
 // GetFileContentAtRef fetches a file at a specific ref from a repo.
diff --git a/gitea/conformance_test.go b/gitea/conformance_test.go
new file mode 100644
index 0000000..08b7f97
--- /dev/null
+++ b/gitea/conformance_test.go
@@ -0,0 +1,25 @@
+//go:build phase2
+
+package gitea_test
+
+import (
+	"gitea.weiker.me/rodin/review-bot/gitea"
+	"gitea.weiker.me/rodin/review-bot/vcs"
+)
+
+// Compile-time interface conformance assertions.
+// These will verify gitea.Client satisfies vcs interfaces once the Phase 2
+// adapter bridges the method signature gaps:
+//
+//   - PRReader: GetPullRequest returns *gitea.PullRequest (needs *vcs.PullRequest)
+//   - PRReader: GetPullRequestFiles returns []gitea.ChangedFile (needs []vcs.ChangedFile)
+//   - FileReader: GetFileContent lacks ref parameter
+//   - Reviewer: PostReview uses (event, body, comments) instead of vcs.ReviewRequest
+//
+// Remove the phase2 build tag once the adapter is complete.
+var (
+	_ vcs.PRReader   = (*gitea.Client)(nil)
+	_ vcs.FileReader = (*gitea.Client)(nil)
+	_ vcs.Reviewer   = (*gitea.Client)(nil)
+	_ vcs.Identity   = (*gitea.Client)(nil)
+)
diff --git a/vcs/util.go b/vcs/util.go
index f1266c8..62f2015 100644
--- a/vcs/util.go
+++ b/vcs/util.go
@@ -37,7 +37,7 @@ func GetAllFilesInPath(ctx context.Context, client FileReader, owner, repo, path
 	var walk func(string) error
 	walk = func(dir string) error {
 		if err := ctx.Err(); err != nil {
-			return fmt.Errorf("context cancelled during traversal: %w", err)
+			return fmt.Errorf("context canceled during traversal: %w", err)
 		}
 
 		entries, err := client.ListContents(ctx, owner, repo, dir)
@@ -47,7 +47,7 @@ func GetAllFilesInPath(ctx context.Context, client FileReader, owner, repo, path
 
 		for _, entry := range entries {
 			if err := ctx.Err(); err != nil {
-				return fmt.Errorf("context cancelled during traversal: %w", err)
+				return fmt.Errorf("context canceled during traversal: %w", err)
 			}
 
 			switch entry.Type {
diff --git a/vcs/util_test.go b/vcs/util_test.go
index 8436884..6d1e42a 100644
--- a/vcs/util_test.go
+++ b/vcs/util_test.go
@@ -2,8 +2,8 @@ package vcs_test
 
 import (
 	"context"
-	"strings"
 	"fmt"
+	"strings"
 	"testing"
 
 	"gitea.weiker.me/rodin/review-bot/vcs"
@@ -306,7 +306,7 @@ func TestGetAllFilesInPath_ErrorPropagation(t *testing.T) {
 		}
 	})
 
-	t.Run("cancelled context propagates", func(t *testing.T) {
+	t.Run("canceled context propagates", func(t *testing.T) {
 		ctx, cancel := context.WithCancel(context.Background())
 		cancel() // Cancel immediately
 
@@ -322,9 +322,9 @@ func TestGetAllFilesInPath_ErrorPropagation(t *testing.T) {
 		}
 		_, err := vcs.GetAllFilesInPath(ctx, client, "owner", "repo", "src")
 		if err == nil {
-			t.Fatal("expected error from cancelled context, got nil")
+			t.Fatal("expected error from canceled context, got nil")
 		}
-		if !strings.Contains(err.Error(), "context cancelled") {
+		if !strings.Contains(err.Error(), "context canceled") {
 			t.Errorf("expected context cancellation error, got: %v", err)
 		}
 	})
-- 
2.47.3