Merge main into watchpr auth failure branch

Keep both sides' additions to client_test.go and adopt main's
EditPROptions -> EditOptions rename.

internal/agent/client_test.go

@@ -105,13 +105,13 @@ func TestEditPRSendsOnlySuppliedFields(t *testing.T) {
 	title, body, empty := "new title", "new body", ""
 	tests := []struct {
 		name string
-		opts EditPROptions
+		opts EditOptions
 		want map[string]any
 	}{
-		{"body only", EditPROptions{Body: &body}, map[string]any{"body": "new body"}},
-		{"title only", EditPROptions{Title: &title}, map[string]any{"title": "new title"}},
-		{"both", EditPROptions{Title: &title, Body: &body}, map[string]any{"title": "new title", "body": "new body"}},
-		{"explicit empty body is sent", EditPROptions{Body: &empty}, map[string]any{"body": ""}},
+		{"body only", EditOptions{Body: &body}, map[string]any{"body": "new body"}},
+		{"title only", EditOptions{Title: &title}, map[string]any{"title": "new title"}},
+		{"both", EditOptions{Title: &title, Body: &body}, map[string]any{"title": "new title", "body": "new body"}},
+		{"explicit empty body is sent", EditOptions{Body: &empty}, map[string]any{"body": ""}},
 	}
 	for _, tt := range tests {
 		t.Run(tt.name, func(t *testing.T) {
@@ -164,7 +164,7 @@ func TestEditPRAPIError(t *testing.T) {
 
 	title := "new title"
 	c := &GiteaClient{BaseURL: srv.URL, Token: "t", HTTP: srv.Client()}
-	_, err := c.EditPR("unkin/repo", 7, EditPROptions{Title: &title})
+	_, err := c.EditPR("unkin/repo", 7, EditOptions{Title: &title})
 	if err == nil {
 		t.Fatal("expected error on 404")
 	}
@@ -810,3 +810,139 @@ func TestWatchAbortsWhenTokenExpiresMidWatch(t *testing.T) {
 		t.Errorf("auth failure logged as a warning %d time(s); it must abort", warned)
 	}
 }
+
+func TestCreateIssueRequestBody(t *testing.T) {
+	var gotPath, gotMethod, gotAuth string
+	var gotBody CreateIssueOptions
+	mux := http.NewServeMux()
+	mux.HandleFunc("/api/v1/repos/unkin/repo/issues", func(w http.ResponseWriter, r *http.Request) {
+		gotPath, gotMethod = r.URL.Path, r.Method
+		gotAuth = r.Header.Get("Authorization")
+		_ = json.NewDecoder(r.Body).Decode(&gotBody)
+		_, _ = io.WriteString(w, `{"number":12,"state":"open","title":"T","html_url":"https://git.unkin.net/unkin/repo/issues/12"}`)
+	})
+	srv := httptest.NewServer(mux)
+	defer srv.Close()
+
+	c := &GiteaClient{BaseURL: srv.URL, Token: "gitea-abc", HTTP: srv.Client()}
+	issue, err := c.CreateIssue("unkin/repo", CreateIssueOptions{Title: "T", Body: "B"})
+	if err != nil {
+		t.Fatalf("CreateIssue: %v", err)
+	}
+	if gotMethod != http.MethodPost || gotPath != "/api/v1/repos/unkin/repo/issues" {
+		t.Errorf("request = %s %s, want POST /api/v1/repos/unkin/repo/issues", gotMethod, gotPath)
+	}
+	if gotAuth != "token gitea-abc" {
+		t.Errorf("auth header = %q, want 'token gitea-abc'", gotAuth)
+	}
+	if gotBody.Title != "T" || gotBody.Body != "B" {
+		t.Errorf("request body = %+v", gotBody)
+	}
+	if issue.Number != 12 || issue.HTMLURL != "https://git.unkin.net/unkin/repo/issues/12" {
+		t.Errorf("parsed issue = %+v", issue)
+	}
+}
+
+// Filing against a repo that does not exist (or that the token may not see)
+// gets Gitea's 404, which must surface as a not-found error carrying the API's
+// own message rather than a bare status.
+func TestCreateIssueRepoNotFound(t *testing.T) {
+	srv := httptest.NewServer(http.HandlerFunc(func(w http.ResponseWriter, r *http.Request) {
+		w.WriteHeader(http.StatusNotFound)
+		_, _ = io.WriteString(w, `{"errors":null,"message":"user redirect does not exist [name: ghost]","url":"https://git.unkin.net/api/swagger"}`)
+	}))
+	defer srv.Close()
+
+	c := &GiteaClient{BaseURL: srv.URL, Token: "t", HTTP: srv.Client()}
+	_, err := c.CreateIssue("ghost/repo", CreateIssueOptions{Title: "T"})
+	if err == nil {
+		t.Fatal("expected error for a repo that does not exist")
+	}
+	if !IsNotFound(err) {
+		t.Errorf("IsNotFound(%v) = false, want true", err)
+	}
+	if !strings.Contains(err.Error(), "user redirect does not exist") {
+		t.Errorf("error %q should carry the API message", err)
+	}
+}
+
+// Any other non-2xx is a plain API failure: reported, not retried, and not
+// mistaken for a missing repo.
+func TestCreateIssueAPIError(t *testing.T) {
+	requests := 0
+	mux := http.NewServeMux()
+	mux.HandleFunc("/api/v1/repos/unkin/repo/issues", func(w http.ResponseWriter, r *http.Request) {
+		requests++
+		w.WriteHeader(http.StatusUnprocessableEntity)
+		_, _ = io.WriteString(w, `{"errors":null,"message":"Validation Error: title is empty","url":"https://git.unkin.net/api/swagger"}`)
+	})
+	srv := httptest.NewServer(mux)
+	defer srv.Close()
+
+	c := &GiteaClient{BaseURL: srv.URL, Token: "t", HTTP: srv.Client()}
+	_, err := c.CreateIssue("unkin/repo", CreateIssueOptions{Title: "T"})
+	if err == nil {
+		t.Fatal("expected error on 422")
+	}
+	if IsNotFound(err) {
+		t.Errorf("a 422 must not read as not-found: %v", err)
+	}
+	if !strings.Contains(err.Error(), "Validation Error") {
+		t.Errorf("error %q should carry the API message", err)
+	}
+	if requests != 1 {
+		t.Errorf("requests = %d, want 1 (a 422 is not retried)", requests)
+	}
+}
+
+// An issue edit sends only the fields it was given, for the same reason a PR
+// edit does: Gitea overwrites whatever key it receives.
+func TestEditIssueSendsOnlySuppliedFields(t *testing.T) {
+	title, body := "new title", "new body"
+	tests := []struct {
+		name string
+		opts EditOptions
+		want map[string]any
+	}{
+		{"body only", EditOptions{Body: &body}, map[string]any{"body": "new body"}},
+		{"title only", EditOptions{Title: &title}, map[string]any{"title": "new title"}},
+		{"both", EditOptions{Title: &title, Body: &body}, map[string]any{"title": "new title", "body": "new body"}},
+	}
+	for _, tt := range tests {
+		t.Run(tt.name, func(t *testing.T) {
+			var gotBody map[string]any
+			var gotMethod, gotPath string
+			mux := http.NewServeMux()
+			mux.HandleFunc("/api/v1/repos/unkin/repo/issues/12", func(w http.ResponseWriter, r *http.Request) {
+				gotMethod, gotPath = r.Method, r.URL.Path
+				_ = json.NewDecoder(r.Body).Decode(&gotBody)
+				_, _ = io.WriteString(w, `{"number":12,"title":"new title","html_url":"https://git.unkin.net/unkin/repo/issues/12"}`)
+			})
+			srv := httptest.NewServer(mux)
+			defer srv.Close()
+
+			c := &GiteaClient{BaseURL: srv.URL, Token: "t", HTTP: srv.Client()}
+			issue, err := c.EditIssue("unkin/repo", 12, tt.opts)
+			if err != nil {
+				t.Fatalf("EditIssue: %v", err)
+			}
+			if gotMethod != http.MethodPatch {
+				t.Errorf("method = %s, want PATCH", gotMethod)
+			}
+			if gotPath != "/api/v1/repos/unkin/repo/issues/12" {
+				t.Errorf("path = %q", gotPath)
+			}
+			if len(gotBody) != len(tt.want) {
+				t.Errorf("payload = %v, want exactly the supplied fields %v", gotBody, tt.want)
+			}
+			for k, v := range tt.want {
+				if gotBody[k] != v {
+					t.Errorf("payload[%q] = %v, want %v", k, gotBody[k], v)
+				}
+			}
+			if issue.Number != 12 || issue.HTMLURL == "" {
+				t.Errorf("parsed issue = %+v", issue)
+			}
+		})
+	}
+}

internal/agent/git.go

@@ -109,6 +109,37 @@ func GitRemoteBranchExists(repoDir, remote, branch string) bool {
 	return err == nil
 }
 
+// GitRevParse resolves ref to a full object id in repoDir.
+func GitRevParse(repoDir, ref string) (string, error) {
+	return runGit(repoDir, "rev-parse", ref)
+}
+
+// GitAheadCount counts commits reachable from head that upstream does not hold.
+func GitAheadCount(repoDir, upstream, head string) (int, error) {
+	out, err := runGit(repoDir, "rev-list", "--count", upstream+".."+head)
+	if err != nil {
+		return 0, err
+	}
+	n, err := strconv.Atoi(strings.TrimSpace(out))
+	if err != nil {
+		return 0, fmt.Errorf("parse rev-list count %q: %w", out, err)
+	}
+	return n, nil
+}
+
+// GitMergeFFOnly advances the branch checked out at dir to ref, failing rather
+// than writing a merge commit when the move is not a fast-forward.
+func GitMergeFFOnly(dir, ref string) error {
+	_, err := runGit(dir, "merge", "--ff-only", ref)
+	return err
+}
+
+// GitSetUpstream points branch at the remote-tracking ref upstream.
+func GitSetUpstream(repoDir, branch, upstream string) error {
+	_, err := runGit(repoDir, "branch", "--set-upstream-to="+upstream, branch)
+	return err
+}
+
 // GitIsDirty reports whether the checkout at dir has uncommitted or untracked
 // changes.
 func GitIsDirty(dir string) (bool, error) {

internal/agent/gitea.go

@@ -273,19 +273,20 @@ func (c *GiteaClient) CreatePR(repoPath string, opts CreatePROptions) (PullReque
 	return pr, err
 }
 
-// EditPROptions are the fields an edit may change. Pointers so an unset field
-// is omitted from the payload entirely, leaving that field as it is. The two
-// fields are not symmetric: Gitea only applies a title when it is non-empty,
-// so Title can be set but never cleared and a "" title is a silent no-op,
-// while a pointer to "" Body really does blank the body.
-type EditPROptions struct {
+// EditOptions are the fields an edit may change, for a pull request or an
+// issue alike. Pointers so an unset field is omitted from the payload
+// entirely, leaving that field as it is. The two fields are not symmetric:
+// Gitea only applies a title when it is non-empty, so Title can be set but
+// never cleared and a "" title is a silent no-op, while a pointer to "" Body
+// really does blank the body.
+type EditOptions struct {
 	Title *string `json:"title,omitempty"`
 	Body  *string `json:"body,omitempty"`
 }
 
 // EditPR updates a pull request's title and/or body
 // (PATCH /api/v1/repos/{owner}/{repo}/pulls/{index}).
-func (c *GiteaClient) EditPR(repoPath string, number int, opts EditPROptions) (PullRequest, error) {
+func (c *GiteaClient) EditPR(repoPath string, number int, opts EditOptions) (PullRequest, error) {
 	var pr PullRequest
 	err := c.do(http.MethodPatch, fmt.Sprintf("/api/v1/repos/%s/pulls/%d", repoPath, number), opts, &pr)
 	return pr, err
@@ -298,6 +299,36 @@ func (c *GiteaClient) GetPR(repoPath string, number int) (PullRequest, error) {
 	return pr, err
 }
 
+// Issue is the subset of Gitea's issue object we track. Gitea numbers issues
+// and pull requests in one sequence, so Number is comparable to a PR number.
+type Issue struct {
+	Number  int    `json:"number"`
+	State   string `json:"state"`
+	Title   string `json:"title"`
+	HTMLURL string `json:"html_url"`
+}
+
+// CreateIssueOptions are the fields for filing an issue.
+type CreateIssueOptions struct {
+	Title string `json:"title"`
+	Body  string `json:"body"`
+}
+
+// CreateIssue files an issue (POST /api/v1/repos/{owner}/{repo}/issues).
+func (c *GiteaClient) CreateIssue(repoPath string, opts CreateIssueOptions) (Issue, error) {
+	var issue Issue
+	err := c.do(http.MethodPost, "/api/v1/repos/"+repoPath+"/issues", opts, &issue)
+	return issue, err
+}
+
+// EditIssue updates an issue's title and/or body
+// (PATCH /api/v1/repos/{owner}/{repo}/issues/{index}).
+func (c *GiteaClient) EditIssue(repoPath string, number int, opts EditOptions) (Issue, error) {
+	var issue Issue
+	err := c.do(http.MethodPatch, fmt.Sprintf("/api/v1/repos/%s/issues/%d", repoPath, number), opts, &issue)
+	return issue, err
+}
+
 // Comment is the subset of an issue comment we track.
 type Comment struct {
 	ID   int64  `json:"id"`
@@ -305,8 +336,10 @@ type Comment struct {
 	Body string `json:"body"`
 }
 
-// CreateComment posts a comment on the PR's issue thread
-// (POST /api/v1/repos/{owner}/{repo}/issues/{n}/comments).
+// CreateComment posts a comment on an issue thread
+// (POST /api/v1/repos/{owner}/{repo}/issues/{n}/comments). Gitea backs a pull
+// request with an issue of the same number, so this is the single path for
+// both.
 func (c *GiteaClient) CreateComment(repoPath string, number int, body string) (Comment, error) {
 	var cm Comment
 	payload := map[string]string{"body": body}