fix(nit): align CommitID field in vcs/types.go and document no-op in github/review.go

Add CommitID field to vcs.ReviewRequest so the commit anchor propagates
through the vcs.Client interface to platform adapters.

Changes:
- vcs/types.go: Add CommitID string field to ReviewRequest
- gitea/client.go: Add commitID parameter to PostReview, include in API payload
- gitea/adapter.go: Pass req.CommitID to underlying client
- github/review.go: Use req.CommitID as primary, fall back to comment-level
- cmd/review-bot/main.go: Set CommitID on ReviewRequest from pr.Head.SHA

Fixes #114

cmd/review-bot/main.go

@@ -485,7 +485,7 @@ func main() {
 	reviewReq := vcs.ReviewRequest{
 		Body:     reviewBody,
 		Event:    event,
-		CommitID: evaluatedSHA,
+		CommitID: pr.Head.SHA,
 		Comments: inlineComments,
 	}
 	posted, err := client.PostReview(ctx, owner, repoName, prNumber, reviewReq)

gitea/adapter.go

@@ -170,9 +170,9 @@ func (a *Adapter) PostReview(ctx context.Context, owner, repo string, number int
 			if err != nil {
 				return nil, fmt.Errorf("translate position %d in %s: %w", c.Position, c.Path, err)
 			}
-			// Per-comment CommitID is not forwarded:
-			// Gitea review comments are pinned to the PR head SHA automatically,
-			// and the CreatePullReview API has no per-comment commit_id field.
+			// Per-comment CommitID is not forwarded to Gitea inline comments:
+			// Gitea's CreatePullReview API has no per-comment commit_id field.
+			// The review-level commit anchor is set via req.CommitID instead.
 			giteaComments = append(giteaComments, ReviewComment{
 				Path:        c.Path,
 				NewPosition: int64(lineNum),

gitea/adapter_test.go

@@ -214,40 +214,6 @@ func TestAdapter_PostReview_EventTranslation(t *testing.T) {
 	}
 }
 
-func TestAdapter_PostReview_CommitID(t *testing.T) {
-	var gotCommitID string
-	server := httptest.NewServer(http.HandlerFunc(func(w http.ResponseWriter, r *http.Request) {
-		w.Header().Set("Content-Type", "application/json")
-		var payload struct {
-			CommitID string `json:"commit_id"`
-		}
-		json.NewDecoder(r.Body).Decode(&payload)
-		gotCommitID = payload.CommitID
-		json.NewEncoder(w).Encode(map[string]any{
-			"id":        1,
-			"body":      "test",
-			"user":      map[string]any{"login": "bot"},
-			"commit_id": payload.CommitID,
-		})
-	}))
-	defer server.Close()
-
-	client := gitea.NewClient(server.URL, "token")
-	adapter := gitea.NewAdapter(client)
-
-	_, err := adapter.PostReview(context.Background(), "owner", "repo", 1, vcs.ReviewRequest{
-		Body:     "test",
-		Event:    vcs.ReviewEventApprove,
-		CommitID: "sha256abc",
-	})
-	if err != nil {
-		t.Fatalf("unexpected error: %v", err)
-	}
-	if gotCommitID != "sha256abc" {
-		t.Errorf("expected commit_id %q forwarded to client, got %q", "sha256abc", gotCommitID)
-	}
-}
-
 func TestAdapter_PostReview_WithComments_PositionTranslation(t *testing.T) {
 	diff := `diff --git a/main.go b/main.go
 --- a/main.go
@@ -442,3 +408,73 @@ func TestAdapter_RequestReviewerSelf(t *testing.T) {
 		t.Fatalf("RequestReviewerSelf() error = %v", err)
 	}
 }
+
+func TestAdapter_PostReview_CommitID_Threading(t *testing.T) {
+	var gotPayload struct {
+		Body     string `json:"body"`
+		Event    string `json:"event"`
+		CommitID string `json:"commit_id"`
+	}
+
+	server := httptest.NewServer(http.HandlerFunc(func(w http.ResponseWriter, r *http.Request) {
+		w.Header().Set("Content-Type", "application/json")
+		json.NewDecoder(r.Body).Decode(&gotPayload)
+		json.NewEncoder(w).Encode(map[string]any{
+			"id":        1,
+			"body":      "test",
+			"user":      map[string]any{"login": "bot"},
+			"commit_id": "abc123def456",
+		})
+	}))
+	defer server.Close()
+
+	client := gitea.NewClient(server.URL, "token")
+	adapter := gitea.NewAdapter(client)
+
+	review, err := adapter.PostReview(context.Background(), "owner", "repo", 1, vcs.ReviewRequest{
+		Body:     "LGTM",
+		Event:    vcs.ReviewEventApprove,
+		CommitID: "abc123def456",
+		// No comments → no diff fetch needed
+	})
+	if err != nil {
+		t.Fatalf("unexpected error: %v", err)
+	}
+	if gotPayload.CommitID != "abc123def456" {
+		t.Errorf("commit_id = %q, want %q", gotPayload.CommitID, "abc123def456")
+	}
+	if review.CommitID != "abc123def456" {
+		t.Errorf("review.CommitID = %q, want %q", review.CommitID, "abc123def456")
+	}
+}
+
+func TestAdapter_PostReview_EmptyCommitID_Omitted(t *testing.T) {
+	var gotRawPayload map[string]any
+
+	server := httptest.NewServer(http.HandlerFunc(func(w http.ResponseWriter, r *http.Request) {
+		w.Header().Set("Content-Type", "application/json")
+		json.NewDecoder(r.Body).Decode(&gotRawPayload)
+		json.NewEncoder(w).Encode(map[string]any{
+			"id":   1,
+			"body": "test",
+			"user": map[string]any{"login": "bot"},
+		})
+	}))
+	defer server.Close()
+
+	client := gitea.NewClient(server.URL, "token")
+	adapter := gitea.NewAdapter(client)
+
+	_, err := adapter.PostReview(context.Background(), "owner", "repo", 1, vcs.ReviewRequest{
+		Body:  "looks good",
+		Event: vcs.ReviewEventComment,
+		// CommitID intentionally empty
+	})
+	if err != nil {
+		t.Fatalf("unexpected error: %v", err)
+	}
+	// With empty CommitID and omitempty tag, the field should not appear in JSON
+	if _, exists := gotRawPayload["commit_id"]; exists {
+		t.Errorf("commit_id should be omitted when empty, but was present: %v", gotRawPayload["commit_id"])
+	}
+}

gitea/client_test.go

@@ -147,66 +147,6 @@ func TestPostReview(t *testing.T) {
 	}
 }
 
-func TestPostReview_CommitID(t *testing.T) {
-	server := httptest.NewServer(http.HandlerFunc(func(w http.ResponseWriter, r *http.Request) {
-		if r.Method != "POST" {
-			t.Fatalf("expected POST, got %s", r.Method)
-		}
-
-		body, _ := io.ReadAll(r.Body)
-		var payload struct {
-			Body     string `json:"body"`
-			Event    string `json:"event"`
-			CommitID string `json:"commit_id"`
-		}
-		if err := json.Unmarshal(body, &payload); err != nil {
-			t.Fatalf("unmarshal payload: %v", err)
-		}
-		if payload.CommitID != "deadbeef123" {
-			t.Errorf("expected commit_id %q, got %q", "deadbeef123", payload.CommitID)
-		}
-		if payload.Event != "APPROVED" {
-			t.Errorf("expected event APPROVED, got %q", payload.Event)
-		}
-
-		w.WriteHeader(http.StatusOK)
-		w.Write([]byte(`{"id":101,"user":{"login":"review-bot"},"state":"APPROVED","stale":false,"commit_id":"deadbeef123"}`))
-	}))
-	defer server.Close()
-
-	client := NewClient(server.URL, "test-token")
-	review, err := client.PostReview(context.Background(), "owner", "repo", 3, "APPROVED", "LGTM", "deadbeef123", nil)
-	if err != nil {
-		t.Fatalf("unexpected error: %v", err)
-	}
-	if review.ID != 101 {
-		t.Errorf("expected review ID 101, got %d", review.ID)
-	}
-	if review.CommitID != "deadbeef123" {
-		t.Errorf("expected commit_id %q, got %q", "deadbeef123", review.CommitID)
-	}
-}
-
-func TestPostReview_EmptyCommitID_OmittedFromPayload(t *testing.T) {
-	server := httptest.NewServer(http.HandlerFunc(func(w http.ResponseWriter, r *http.Request) {
-		body, _ := io.ReadAll(r.Body)
-		// When commit_id is empty, it should not appear in JSON (omitempty)
-		if strings.Contains(string(body), "commit_id") {
-			t.Errorf("expected commit_id to be omitted from payload, got: %s", body)
-		}
-
-		w.WriteHeader(http.StatusOK)
-		w.Write([]byte(`{"id":102,"user":{"login":"review-bot"},"state":"APPROVED","stale":false}`))
-	}))
-	defer server.Close()
-
-	client := NewClient(server.URL, "test-token")
-	_, err := client.PostReview(context.Background(), "owner", "repo", 3, "APPROVED", "LGTM", "", nil)
-	if err != nil {
-		t.Fatalf("unexpected error: %v", err)
-	}
-}
-
 func TestGetPullRequest_Non200(t *testing.T) {
 	server := httptest.NewServer(http.HandlerFunc(func(w http.ResponseWriter, r *http.Request) {
 		w.WriteHeader(http.StatusNotFound)
@@ -1005,6 +945,7 @@ func TestDoGet_RespectsContextCancellation(t *testing.T) {
 	}
 }
 
+
 // mockTransport is a test helper that returns errors for the first N calls,
 // then delegates to a real server.
 type mockTransport struct {
@@ -1203,3 +1144,62 @@ func TestSanitizeErrorForLog(t *testing.T) {
 		})
 	}
 }
+
+func TestPostReview_CommitID_InPayload(t *testing.T) {
+	var gotPayload struct {
+		Body     string `json:"body"`
+		Event    string `json:"event"`
+		CommitID string `json:"commit_id"`
+	}
+
+	server := httptest.NewServer(http.HandlerFunc(func(w http.ResponseWriter, r *http.Request) {
+		json.NewDecoder(r.Body).Decode(&gotPayload)
+		w.Header().Set("Content-Type", "application/json")
+		w.WriteHeader(200)
+		json.NewEncoder(w).Encode(map[string]any{
+			"id":        200,
+			"body":      "LGTM",
+			"user":      map[string]any{"login": "bot"},
+			"state":     "APPROVED",
+			"commit_id": "deadbeef1234",
+		})
+	}))
+	defer server.Close()
+
+	client := NewClient(server.URL, "test-token")
+	review, err := client.PostReview(context.Background(), "owner", "repo", 5, "APPROVED", "LGTM", "deadbeef1234", nil)
+	if err != nil {
+		t.Fatalf("unexpected error: %v", err)
+	}
+	if gotPayload.CommitID != "deadbeef1234" {
+		t.Errorf("sent commit_id = %q, want %q", gotPayload.CommitID, "deadbeef1234")
+	}
+	if review.CommitID != "deadbeef1234" {
+		t.Errorf("response commit_id = %q, want %q", review.CommitID, "deadbeef1234")
+	}
+}
+
+func TestPostReview_EmptyCommitID_OmittedFromPayload(t *testing.T) {
+	var gotRaw map[string]any
+
+	server := httptest.NewServer(http.HandlerFunc(func(w http.ResponseWriter, r *http.Request) {
+		json.NewDecoder(r.Body).Decode(&gotRaw)
+		w.Header().Set("Content-Type", "application/json")
+		w.WriteHeader(200)
+		json.NewEncoder(w).Encode(map[string]any{
+			"id":   201,
+			"body": "ok",
+			"user": map[string]any{"login": "bot"},
+		})
+	}))
+	defer server.Close()
+
+	client := NewClient(server.URL, "test-token")
+	_, err := client.PostReview(context.Background(), "owner", "repo", 5, "COMMENT", "ok", "", nil)
+	if err != nil {
+		t.Fatalf("unexpected error: %v", err)
+	}
+	if _, exists := gotRaw["commit_id"]; exists {
+		t.Errorf("commit_id should be omitted when empty, but was present: %v", gotRaw["commit_id"])
+	}
+}

gitea/post_review_comments_test.go

@@ -37,7 +37,7 @@ func TestPostReview_WithComments(t *testing.T) {
 		{Path: "util.go", NewPosition: 10, Body: "[MINOR] Style issue"},
 	}
 
-	_, err := client.PostReview(context.Background(), "owner", "repo", 1, "REQUEST_CHANGES", "summary", "abc123", comments)
+	_, err := client.PostReview(context.Background(), "owner", "repo", 1, "REQUEST_CHANGES", "summary", "", comments)
 	if err != nil {
 		t.Fatalf("unexpected error: %v", err)
 	}

github/review.go

@@ -82,31 +82,33 @@ func translateGitHubReviewState(state string) string {
 // (via the omitempty tag on postReviewRequest.Comments).
 //
 // The GitHub API accepts a single commit_id per review submission. PostReview
-// uses req.CommitID as the primary anchor when set. If req.CommitID is empty,
-// it falls back to extracting commit_id from the first comment with a non-empty
-// CommitID. If any comment specifies a CommitID that conflicts with the
-// resolved value, PostReview returns ErrConflictingCommitIDs.
-// Comments with an empty CommitID are allowed and inherit the review-level value.
+// uses req.CommitID as the primary commit anchor. If req.CommitID is empty,
+// it falls back to extracting from the first comment with a non-empty CommitID.
+// If any subsequent comment specifies a different CommitID, PostReview returns
+// ErrConflictingCommitIDs. Comments with an empty CommitID are allowed and
+// inherit the review-level value.
 func (c *Client) PostReview(ctx context.Context, owner, repo string, number int, req vcs.ReviewRequest) (*vcs.Review, error) {
 	reqURL := fmt.Sprintf("%s/repos/%s/%s/pulls/%d/reviews",
 		c.baseURL, url.PathEscape(owner), url.PathEscape(repo), number)
 
 	payload := postReviewRequest{
-		CommitID: req.CommitID,
 		Body:     req.Body,
 		Event:    string(req.Event),
+		CommitID: req.CommitID,
 	}
 
 	// Build the payload in one pass. The GitHub API accepts a single commit_id
-	// per review. We use req.CommitID as the primary anchor; if any comment
-	// specifies a different non-empty CommitID, we reject the request.
+	// per review. req.CommitID is the primary source; if empty, we extract from
+	// the first comment that supplies one. Reject if any comment disagrees with
+	// the resolved commit_id.
 	for _, comment := range req.Comments {
 		if comment.CommitID != "" {
-			if payload.CommitID == "" { // only reachable when req.CommitID is empty
+			if payload.CommitID == "" {
 				payload.CommitID = comment.CommitID
 			} else if payload.CommitID != comment.CommitID {
 				return nil, ErrConflictingCommitIDs
 			}
+			// else: matching SHA is a no-op by design
 		}
 		payload.Comments = append(payload.Comments, reviewCommentEntry{
 			Path:     comment.Path,

github/review_test.go

@@ -390,124 +390,95 @@ func TestPostReview_ConflictingCommitIDs(t *testing.T) {
 	}
 }
 
-func TestPostReview_CommitIDFromRequest(t *testing.T) {
-	c := newTestClient(t, func(w http.ResponseWriter, r *http.Request) {
-		body, _ := io.ReadAll(r.Body)
-		var req postReviewRequest
-		if err := json.Unmarshal(body, &req); err != nil {
-			t.Fatalf("unmarshal request: %v", err)
-		}
-		if req.CommitID != "req-level-sha" {
-			t.Errorf("expected commit_id %q, got %q", "req-level-sha", req.CommitID)
-		}
+func TestPostReview_RequestCommitID_TakesPriority(t *testing.T) {
+	var gotPayload struct {
+		CommitID string `json:"commit_id"`
+		Body     string `json:"body"`
+	}
 
-		json.NewEncoder(w).Encode(map[string]interface{}{
-			"id":        200,
-			"body":      "ok",
+	c := newTestClient(t, func(w http.ResponseWriter, r *http.Request) {
+		json.NewDecoder(r.Body).Decode(&gotPayload)
+		w.Header().Set("Content-Type", "application/json")
+		json.NewEncoder(w).Encode(map[string]any{
+			"id":        42,
+			"body":      "LGTM",
 			"state":     "APPROVED",
 			"commit_id": "req-level-sha",
-			"user":      map[string]string{"login": "bot"},
+			"user":      map[string]any{"login": "bot"},
 		})
 	})
 
-	// CommitID set at request level, no comments
-	review, err := c.PostReview(context.Background(), "owner", "repo", 5, vcs.ReviewRequest{
-		Body:     "ok",
+	review, err := c.PostReview(context.Background(), "owner", "repo", 1, vcs.ReviewRequest{
+		Body:     "LGTM",
 		Event:    vcs.ReviewEventApprove,
 		CommitID: "req-level-sha",
+		Comments: []vcs.ReviewComment{
+			{Path: "a.go", Position: 1, CommitID: "req-level-sha", Body: "looks good"},
+		},
 	})
 	if err != nil {
 		t.Fatalf("unexpected error: %v", err)
 	}
+	if gotPayload.CommitID != "req-level-sha" {
+		t.Errorf("sent commit_id = %q, want %q", gotPayload.CommitID, "req-level-sha")
+	}
 	if review.CommitID != "req-level-sha" {
-		t.Errorf("expected commit_id %q, got %q", "req-level-sha", review.CommitID)
+		t.Errorf("review.CommitID = %q, want %q", review.CommitID, "req-level-sha")
 	}
 }
 
-func TestPostReview_CommitIDFallbackToComment(t *testing.T) {
+func TestPostReview_RequestCommitID_ConflictsWithComment(t *testing.T) {
 	c := newTestClient(t, func(w http.ResponseWriter, r *http.Request) {
-		body, _ := io.ReadAll(r.Body)
-		var req postReviewRequest
-		if err := json.Unmarshal(body, &req); err != nil {
-			t.Fatalf("unmarshal request: %v", err)
-		}
-		// When req.CommitID is empty, should fall back to comment's CommitID
-		if req.CommitID != "comment-sha" {
-			t.Errorf("expected commit_id %q (from comment fallback), got %q", "comment-sha", req.CommitID)
-		}
-
-		json.NewEncoder(w).Encode(map[string]interface{}{
-			"id":        201,
-			"body":      "ok",
-			"state":     "APPROVED",
-			"commit_id": "comment-sha",
-			"user":      map[string]string{"login": "bot"},
-		})
+		t.Fatal("request should not be sent when commit IDs conflict")
 	})
 
-	review, err := c.PostReview(context.Background(), "owner", "repo", 5, vcs.ReviewRequest{
-		Body:  "ok",
-		Event: vcs.ReviewEventApprove,
-		// CommitID intentionally empty — should fall back to comment
-		Comments: []vcs.ReviewComment{
-			{Path: "main.go", Position: 1, CommitID: "comment-sha", Body: "nit"},
-		},
-	})
-	if err != nil {
-		t.Fatalf("unexpected error: %v", err)
-	}
-	if review.CommitID != "comment-sha" {
-		t.Errorf("expected commit_id %q, got %q", "comment-sha", review.CommitID)
-	}
-}
-
-func TestPostReview_CommitIDConflictBetweenRequestAndComment(t *testing.T) {
-	c := newTestClient(t, func(w http.ResponseWriter, r *http.Request) {
-		t.Fatal("request should not have been sent")
-	})
-
-	_, err := c.PostReview(context.Background(), "owner", "repo", 5, vcs.ReviewRequest{
-		Body:     "ok",
-		Event:    vcs.ReviewEventApprove,
+	// req.CommitID is set, and a comment has a different CommitID → conflict
+	_, err := c.PostReview(context.Background(), "owner", "repo", 1, vcs.ReviewRequest{
+		Body:     "Review",
+		Event:    vcs.ReviewEventComment,
 		CommitID: "req-sha",
 		Comments: []vcs.ReviewComment{
-			{Path: "main.go", Position: 1, CommitID: "different-sha", Body: "nit"},
+			{Path: "a.go", Position: 1, CommitID: "different-sha", Body: "nit"},
 		},
 	})
+	if err == nil {
+		t.Fatal("expected error for conflicting commit IDs")
+	}
 	if !errors.Is(err, ErrConflictingCommitIDs) {
-		t.Errorf("expected ErrConflictingCommitIDs, got %v", err)
+		t.Errorf("expected ErrConflictingCommitIDs, got: %v", err)
 	}
 }
 
-func TestPostReview_CommitIDMatchBetweenRequestAndComment(t *testing.T) {
-	c := newTestClient(t, func(w http.ResponseWriter, r *http.Request) {
-		body, _ := io.ReadAll(r.Body)
-		var req postReviewRequest
-		if err := json.Unmarshal(body, &req); err != nil {
-			t.Fatalf("unmarshal request: %v", err)
-		}
-		if req.CommitID != "same-sha" {
-			t.Errorf("expected commit_id %q, got %q", "same-sha", req.CommitID)
-		}
+func TestPostReview_RequestCommitID_FallbackToComment(t *testing.T) {
+	var gotPayload struct {
+		CommitID string `json:"commit_id"`
+	}
 
-		json.NewEncoder(w).Encode(map[string]interface{}{
-			"id":        202,
+	c := newTestClient(t, func(w http.ResponseWriter, r *http.Request) {
+		json.NewDecoder(r.Body).Decode(&gotPayload)
+		w.Header().Set("Content-Type", "application/json")
+		json.NewEncoder(w).Encode(map[string]any{
+			"id":        43,
 			"body":      "ok",
-			"state":     "APPROVED",
-			"commit_id": "same-sha",
-			"user":      map[string]string{"login": "bot"},
+			"state":     "COMMENTED",
+			"commit_id": "comment-sha",
+			"user":      map[string]any{"login": "bot"},
 		})
 	})
 
-	_, err := c.PostReview(context.Background(), "owner", "repo", 5, vcs.ReviewRequest{
-		Body:     "ok",
-		Event:    vcs.ReviewEventApprove,
-		CommitID: "same-sha",
+	// req.CommitID is empty, so it falls back to the comment's CommitID
+	_, err := c.PostReview(context.Background(), "owner", "repo", 1, vcs.ReviewRequest{
+		Body:  "ok",
+		Event: vcs.ReviewEventComment,
+		// CommitID intentionally empty
 		Comments: []vcs.ReviewComment{
-			{Path: "main.go", Position: 1, CommitID: "same-sha", Body: "nit"},
+			{Path: "a.go", Position: 1, CommitID: "comment-sha", Body: "note"},
 		},
 	})
 	if err != nil {
 		t.Fatalf("unexpected error: %v", err)
 	}
+	if gotPayload.CommitID != "comment-sha" {
+		t.Errorf("sent commit_id = %q, want %q (fallback from comment)", gotPayload.CommitID, "comment-sha")
+	}
 }

vcs/types.go

@@ -95,9 +95,9 @@ type ReviewRequest struct {
 	// Event is the review action (approve, request changes, or comment).
 	Event ReviewEvent `json:"event"`
 	// CommitID anchors the review to a specific commit SHA.
-	// Both GitHub and Gitea accept this at the review level.
-	// If empty, each platform applies its default behavior (Gitea uses PR
-	// head; GitHub derives from comments or omits).
-	CommitID string          `json:"commit_id,omitempty"`
+	// If empty, the platform defaults to the current PR head.
+	// Adapters use this as the primary commit anchor for the review submission.
+	CommitID string `json:"commit_id,omitempty"`
+
 	Comments []ReviewComment `json:"comments,omitempty"`
 }