feat: routes grouping

3 files changed, 178 insertions, 0 deletions

diff --git a/group.go b/group.go
new file mode 100644
index 0000000..7cb56ad
--- /dev/null
+++ b/group.go
@@ -0,0 +1,50 @@
+package growel
+
+import (
+	"strings"
+)
+
+/* constructor  */
+
+// Engine.Group creates a Group
+// pass the Group as a parameter to the callback function
+// used to create route groups
+func (e *Engine) Group(prefix string, fn func(*Group)) {
+	g := &Group{
+		prefix: prefix,
+		engine: e,
+	}
+
+	fn(g)
+}
+
+/* Inherit Engine methods */
+
+func (g *Group) GET(path string, handler Handler) {
+	full := joinPath(g.prefix, path)
+	g.engine.GET(full, handler)
+}
+
+func (g *Group) POST(path string, handler Handler) {
+	full := joinPath(g.prefix, path)
+	g.engine.POST(full, handler)
+}
+
+func (g *Group) DELETE(path string, handler Handler) {
+	full := joinPath(g.prefix, path)
+	g.engine.DELETE(full, handler)
+}
+
+func (g *Group) PUT(path string, handler Handler) {
+	full := joinPath(g.prefix, path)
+	g.engine.PUT(full, handler)
+}
+
+/* utils */
+
+func joinPath(a, b string) string {
+	if a == "/" {
+		return a + strings.TrimPrefix(b, "/")
+	}
+	return strings.TrimSuffix(a, "/") + "/" + strings.TrimPrefix(b, "/")
+}
diff --git a/group_test.go b/group_test.go
new file mode 100644
index 0000000..e682f09
--- /dev/null
+++ b/group_test.go
@@ -0,0 +1,123 @@
+package growel
+
+import (
+	"net/http"
+	"net/http/httptest"
+	"testing"
+)
+
+/*
+   ======================================================
+                     Test Group()
+   ======================================================
+*/
+
+func TestGroupCallback(t *testing.T) {
+	e := New()
+
+	called := false
+
+	e.Group("/user", func(g *Group) {
+		if g.prefix != "/user" {
+			t.Fatalf("expected prefix '/user', got '%s'", g.prefix)
+		}
+		if g.engine != e {
+			t.Fatal("group.engine does not point to Engine")
+		}
+		called = true
+	})
+
+	if !called {
+		t.Fatal("Group callback not invoked")
+	}
+}
+
+/*
+   ======================================================
+                 Test route registration
+   ======================================================
+*/
+
+func TestGroupRouteRegistration(t *testing.T) {
+	e := New()
+
+	e.Group("/api", func(api *Group) {
+		api.GET("/ping", func(c *Context) {})
+		api.POST("/user", func(c *Context) {})
+		api.PUT("/v1/item/", func(c *Context) {})
+		api.DELETE("/v1/item/42", func(c *Context) {})
+	})
+
+	routes := e.router.routes
+
+	if len(routes) != 4 {
+		t.Fatalf("expected 4 routes, got %d", len(routes))
+	}
+
+	cases := []struct {
+		method string
+		path   string
+	}{
+		{"GET", "/api/ping"},
+		{"POST", "/api/user"},
+		{"PUT", "/api/v1/item"},
+		{"DELETE", "/api/v1/item/42"},
+	}
+
+	for _, want := range cases {
+		found := false
+
+		for _, r := range routes {
+			joined := "/" + joinParts(r.parts)
+			if r.method == want.method && joined == want.path {
+				found = true
+				break
+			}
+		}
+
+		if !found {
+			t.Errorf("missing expected route: %s %s", want.method, want.path)
+		}
+	}
+}
+
+// helper: convert []string{"api","ping"} → "api/ping"
+func joinParts(parts []string) string {
+	out := ""
+	for i, p := range parts {
+		if i > 0 {
+			out += "/"
+		}
+		out += p
+	}
+	return out
+}
+
+/*
+   ======================================================
+              End-to-End ServeHTTP test
+   ======================================================
+*/
+
+func TestGroupServeHTTP(t *testing.T) {
+	e := New()
+
+	e.Group("/hello", func(h *Group) {
+		h.GET("/world", func(c *Context) {
+			c.Plain(200, "ok")
+		})
+	})
+
+	w := httptest.NewRecorder()
+	req, _ := http.NewRequest("GET", "/hello/world", nil)
+
+	e.ServeHTTP(w, req)
+
+	if w.Code != 200 {
+		t.Fatalf("expected 200, got %d", w.Code)
+	}
+
+	if body := w.Body.String(); body != "ok\n" && body != "ok" {
+		t.Fatalf("expected body 'ok', got '%s'", body)
+	}
+}
diff --git a/types.go b/types.go
index 45bdf2c..df3e496 100644
--- a/types.go
+++ b/types.go
@@ -24,3 +24,8 @@ type Router struct {
 type Engine struct {
 	router *Router
 }
+
+type Group struct {
+	prefix string
+	engine *Engine
+}