Web mirror: handler constructor and e2e tests

examples/gallery/web.go

@@ -35,6 +35,13 @@ type mirror struct {
 }
 
 func serveWeb(addr string, view func(c *ui.Context)) error {
+	_, h := newMirror(view)
+	slog.Info("gallery: web mirror listening", "addr", "http://"+addr)
+	return http.ListenAndServe(addr, h)
+}
+
+// newMirror starts the frame loop of view and returns its HTTP handler.
+func newMirror(view func(c *ui.Context)) (*mirror, http.Handler) {
 	m := &mirror{
 		tt:   ui.NewTester(view, 1200, 800),
 		seed: maphash.MakeSeed(),
@@ -52,8 +59,7 @@ func serveWeb(addr string, view func(c *ui.Context)) error {
 	mux.HandleFunc("GET /frame.png", m.serveFrame)
 	mux.HandleFunc("GET /events", m.serveEvents)
 	mux.HandleFunc("POST /input", m.serveInput)
-	slog.Info("gallery: web mirror listening", "addr", "http://"+addr)
-	return http.ListenAndServe(addr, mux)
+	return m, mux
 }
 
 // loop draws frames while the picture keeps changing, then sleeps.

examples/gallery/web_test.go

@@ -0,0 +1,135 @@
+package main
+
+import (
+	"bufio"
+	"bytes"
+	"encoding/json"
+	"io"
+	"net/http"
+	"net/http/httptest"
+	"strings"
+	"testing"
+
+	"github.com/egoist/mygo/ui"
+
+	mujica "mujicaui"
+)
+
+// mirrorRig serves a one-field view through the web mirror.
+type mirrorRig struct {
+	t    *testing.T
+	m    *mirror
+	srv  *httptest.Server
+	text string
+}
+
+func newMirrorRig(t *testing.T) *mirrorRig {
+	r := &mirrorRig{t: t}
+	var h http.Handler
+	r.m, h = newMirror(func(c *ui.Context) {
+		mujica.Use(c, mujica.Settings{})
+		ui.Column(c).Padding(40).Children(func() {
+			mujica.TextInput(c, &r.text, mujica.TextInputOptions{Label: "Ledger"})
+		})
+	})
+	r.srv = httptest.NewServer(h)
+	t.Cleanup(r.srv.Close)
+	return r
+}
+
+func (r *mirrorRig) post(in input) int {
+	r.t.Helper()
+	body, err := json.Marshal(in)
+	if err != nil {
+		r.t.Fatal(err)
+	}
+	res, err := http.Post(r.srv.URL+"/input", "application/json", bytes.NewReader(body))
+	if err != nil {
+		r.t.Fatal(err)
+	}
+	res.Body.Close()
+	return res.StatusCode
+}
+
+func (r *mirrorRig) get(path string) []byte {
+	r.t.Helper()
+	res, err := http.Get(r.srv.URL + path)
+	if err != nil {
+		r.t.Fatal(err)
+	}
+	defer res.Body.Close()
+	if res.StatusCode != http.StatusOK {
+		r.t.Fatalf("GET %s: %d", path, res.StatusCode)
+	}
+	b, err := io.ReadAll(res.Body)
+	if err != nil {
+		r.t.Fatal(err)
+	}
+	return b
+}
+
+func (r *mirrorRig) value() string {
+	r.m.mu.Lock()
+	defer r.m.mu.Unlock()
+	return r.text
+}
+
+func TestMirrorServesPageAndFirstNotice(t *testing.T) {
+	r := newMirrorRig(t)
+	if page := r.get("/"); !bytes.Contains(page, []byte("<canvas id=\"screen\"")) {
+		t.Fatal("index has no canvas")
+	}
+	res, err := http.Get(r.srv.URL + "/events")
+	if err != nil {
+		t.Fatal(err)
+	}
+	defer res.Body.Close()
+	line, err := bufio.NewReader(res.Body).ReadString('\n')
+	if err != nil {
+		t.Fatal(err)
+	}
+	if !strings.HasPrefix(line, `data: {"seq":`) {
+		t.Fatalf("first event %q", line)
+	}
+}
+
+func TestMirrorTypingAndIMEReachTheView(t *testing.T) {
+	r := newMirrorRig(t)
+	before := r.get("/frame.png")
+	if code := r.post(input{Type: "key", Code: "Tab"}); code != http.StatusNoContent {
+		t.Fatalf("tab: %d", code)
+	}
+	for _, ch := range "Ave" {
+		r.post(input{Type: "key", Code: "Key" + strings.ToUpper(string(ch)), Text: string(ch), Mods: []bool{ch == 'A'}})
+	}
+	r.post(input{Type: "compose", Text: "宫廷", Caret: 2})
+	r.post(input{Type: "compose"})
+	r.post(input{Type: "text", Text: "宫廷"})
+	if got := r.value(); got != "Ave宫廷" {
+		t.Fatalf("value %q, want %q", got, "Ave宫廷")
+	}
+	if bytes.Equal(before, r.get("/frame.png")) {
+		t.Fatal("frame did not change after typing")
+	}
+}
+
+func TestMirrorRejectsBadInput(t *testing.T) {
+	r := newMirrorRig(t)
+	for name, in := range map[string]input{
+		"unknown type":  {Type: "teleport"},
+		"unmapped code": {Type: "key", Code: "Hyper"},
+		"tiny window":   {Type: "resize", W: 10, H: 10, Scale: 1},
+	} {
+		if code := r.post(in); code != http.StatusBadRequest {
+			t.Errorf("%s: %d, want 400", name, code)
+		}
+	}
+	res, err := http.Post(r.srv.URL+"/input", "application/json", strings.NewReader("{"))
+	if err != nil {
+		t.Fatal(err)
+	}
+	res.Body.Close()
+	if res.StatusCode != http.StatusBadRequest {
+		t.Fatalf("bad json: %d", res.StatusCode)
+	}
+}