refactor!: remove sub-router support

Author: tigerwill90

README.md

@@ -30,7 +30,7 @@ The current API is not yet stabilized. Breaking changes may occur before `v1.0.0
 
 **Flexible routing:** Fox strikes a balance between routing flexibility, performance and clarity by enforcing clear priority rules, ensuring that
 there are no unintended matches and maintaining high performance even for complex routing patterns. Supported features include named parameters,
-suffix and infix catch-all, regexp constraints, hostname matching, method and method-less routes, route matchers, and sub-routers.
+suffix and infix catch-all, regexp constraints, hostname matching, method and method-less routes, and route matchers.
 
 **Trailing slash handling:** Automatically handle trailing slash inconsistencies by either ignoring them, redirecting to 
 the canonical path, or enforcing strict matching based on your needs.
@@ -51,7 +51,6 @@ the canonical path, or enforcing strict matching based on your needs.
   * [Named wildcards](#named-wildcards-catch-all)
   * [Route matchers](#route-matchers)
   * [Method-less routes](#method-less-routes)
-  * [Sub-Routers](#sub-routers)
   * [Hostname validation & restrictions](#hostname-validation--restrictions)
   * [Path encoding](#path-encoding)
   * [Priority rules](#priority-rules)
@@ -250,28 +249,6 @@ f.MustAdd(fox.MethodGet, "/resource", GetHandler)
 f.MustAdd(fox.MethodAny, "/resource", FallbackHandler)
 ````
 
-#### Sub-Routers
-Fox provides a composable routing API where routers can be mounted as regular routes, each with its own middleware and configuration.
-
-```go
-api := fox.MustRouter(fox.WithMiddleware(AuthMiddleware()))
-api.MustAdd([]string{http.MethodHead, http.MethodGet}, "/", HelloHandler)
-api.MustAdd([]string{http.MethodHead, http.MethodGet}, "/users", ListUser)
-api.MustAdd([]string{http.MethodHead, http.MethodGet}, "/users/{id}", GetUser)
-api.MustAdd(fox.MethodPost, "/users", CreateUser)
-
-f := fox.MustRouter(fox.DefaultOptions())
-f.MustAdd([]string{http.MethodHead, http.MethodGet}, "/*{filepath}", fox.WrapH(http.FileServer(http.Dir("./public/"))))
-f.MustAdd(fox.MethodAny, "/api*{mount}", fox.Sub(api))
-```
-
-Requests matching the prefix are delegated to the mounted router with the remaining path.
-
-Use cases include:
-- Applying middleware, matchers or other configuration to a route prefix
-- Managing entire route subtree at runtime (e.g. insert, update, or delete via the parent router)
-- Organizing routes into groups with shared configuration
-
 #### Hostname validation & restrictions
 
 Hostnames are validated to conform to the [LDH (letters, digits, hyphens) rule](https://datatracker.ietf.org/doc/html/rfc3696.html#section-2)
@@ -643,44 +620,6 @@ func main() {
 }
 ````
 
-Alternatively, you can use a sub-router to apply CORS only to a specific section of your API.
-
-````go
-package main
-
-import (
-	"log"
-	"net/http"
-
-	"github.com/jub0bs/cors"
-	"github.com/fox-toolkit/fox"
-)
-
-func main() {
-	corsMw, err := cors.NewMiddleware(cors.Config{
-		Origins:        []string{"https://example.com"},
-		Methods:        []string{http.MethodHead, http.MethodGet, http.MethodPost},
-		RequestHeaders: []string{"Authorization"},
-	})
-	if err != nil {
-		log.Fatal(err)
-	}
-	corsMw.SetDebug(true) // turn debug mode on (optional)
-
-	f := fox.MustRouter()
-	f.MustAdd([]string{http.MethodHead, http.MethodGet}, "/*{filepath}", fox.WrapH(http.FileServer(http.Dir("./public/"))))
-
-	api := fox.MustRouter(
-		fox.WithAutoOptions(true), // let Fox automatically handle OPTIONS requests
-		fox.WithMiddlewareFor(fox.RouteHandler|fox.OptionsHandler, fox.WrapM(corsMw.Wrap)),
-	)
-	api.MustAdd([]string{http.MethodHead, http.MethodGet}, "/users", ListUsers)
-	api.MustAdd(fox.MethodPost, "/users", CreateUser)
-
-	f.MustAdd(fox.MethodAny, "/api*{any}", fox.Sub(api)) // note: Method-less route
-}
-````
-
 The CORS protocol is complex and security-sensitive. We do **NOT** recommend implementing CORS handling manually. Instead,
 consider using [jub0bs/cors](https://github.com/jub0bs/cors), which performs extensive validation before allowing middleware creation, helping you avoid common pitfalls.
 

benchmark_test.go

@@ -271,37 +271,6 @@ func BenchmarkContext_CloneWith(b *testing.B) {
 	}
 }
 
-func BenchmarkSubRouter(b *testing.B) {
-
-	main := MustRouter()
-	sub1 := MustRouter()
-	sub2 := MustRouter()
-
-	sub2.MustAdd(MethodGet, "/users/email", emptyHandler)
-	sub1.MustAdd(MethodAny, "/{name}/*{any}", Sub(sub2))
-	main.MustAdd(MethodAny, "/{v1}/*{any}", Sub(sub1))
-
-	req := httptest.NewRequest(http.MethodGet, "/v1/john/users/email", nil)
-	w := new(mockResponseWriter)
-
-	b.ResetTimer()
-	b.ReportAllocs()
-	for range b.N {
-		main.ServeHTTP(w, req)
-	}
-}
-
-func BenchmarkStaticAllSubRouter(b *testing.B) {
-	f := MustRouter()
-	sub := MustRouter()
-	for _, route := range staticRoutes {
-		require.NoError(b, onlyError(sub.Add([]string{route.method}, route.path, emptyHandler)))
-	}
-	f.MustAdd(MethodAny, "example.com/*{any}", Sub(sub))
-
-	benchRoute(b, f, staticRoutes)
-}
-
 func BenchmarkVeryLongPattern(b *testing.B) {
 	f := MustRouter()
 	f.MustAdd(MethodGet, "/hello/very_very_very_very_very_very_very_very_very_very_very_very_very_very_very_very_very_very_very_very_very_very_very_very_very_very_very_very", emptyHandler)

context.go

@@ -12,7 +12,6 @@ import (
 	"net/http"
 	"net/url"
 	"slices"
-	"strings"
 
 	"github.com/fox-toolkit/fox/internal/bytesconv"
 	"github.com/fox-toolkit/fox/internal/netutil"
@@ -71,8 +70,6 @@ type Context struct {
 	w             ResponseWriter
 	req           *http.Request
 	params        *[]string
-	paramsKeys    *[]string
-	subPatterns   *[]string
 	skipStack     *skipStack
 	route         *Route
 	tree          *iTree  // no reset
@@ -94,8 +91,6 @@ func (c *Context) reset(w http.ResponseWriter, r *http.Request) {
 	c.cachedQueries = nil
 	c.scope = RouteHandler
 	*c.params = (*c.params)[:0]
-	*c.paramsKeys = (*c.paramsKeys)[:0]
-	*c.subPatterns = (*c.subPatterns)[:0]
 }
 
 func (c *Context) resetNil() {
@@ -104,8 +99,6 @@ func (c *Context) resetNil() {
 	c.cachedQueries = nil
 	c.route = nil
 	*c.params = (*c.params)[:0]
-	*c.paramsKeys = (*c.paramsKeys)[:0]
-	*c.subPatterns = (*c.subPatterns)[:0]
 }
 
 // resetWithRequest resets the [Context] to its initial state, with the provided [http.Request]. This is used
@@ -126,8 +119,6 @@ func (c *Context) resetWithWriter(w ResponseWriter, r *http.Request) {
 	c.cachedQueries = nil
 	c.scope = RouteHandler
 	*c.params = (*c.params)[:0]
-	*c.paramsKeys = (*c.paramsKeys)[:0]
-	*c.subPatterns = (*c.subPatterns)[:0]
 }
 
 // Request returns the [http.Request].
@@ -189,9 +180,8 @@ func (c *Context) ClientIP() (*net.IPAddr, error) {
 // Params returns an iterator over the matched wildcard parameters for the current route.
 func (c *Context) Params() iter.Seq[Param] {
 	return func(yield func(Param) bool) {
-		keys := c.keys()
 		for i, p := range *c.params {
-			if !yield(Param{Key: keys[i], Value: p}) {
+			if !yield(Param{Key: c.route.params[i], Value: p}) {
 				return
 			}
 		}
@@ -200,25 +190,14 @@ func (c *Context) Params() iter.Seq[Param] {
 
 // Param retrieve a matching wildcard segment by name.
 func (c *Context) Param(name string) string {
-	keys := c.keys()
 	for i, p := range *c.params {
-		if keys[i] == name {
+		if c.route.params[i] == name {
 			return p
 		}
 	}
 	return ""
 }
 
-func (c *Context) keys() []string {
-	if len(*c.paramsKeys) > 0 {
-		return *c.paramsKeys
-	}
-	if c.route != nil {
-		return c.route.params
-	}
-	return nil
-}
-
 // Method returns the request method.
 func (c *Context) Method() string {
 	return c.req.Method
@@ -275,20 +254,7 @@ func (c *Context) Header(key string) string {
 
 // Pattern returns the registered route pattern or an empty string if the handler is called in a scope other than [RouteHandler].
 func (c *Context) Pattern() string {
-	switch len(*c.subPatterns) {
-	case 0:
-		return c.pattern
-	case 1:
-		return (*c.subPatterns)[0] + c.pattern
-	}
-
-	var sb strings.Builder
-	sb.Grow(len(c.pattern) + sumLen(*c.subPatterns))
-	for _, p := range *c.subPatterns {
-		sb.WriteString(p)
-	}
-	sb.WriteString(c.pattern)
-	return sb.String()
+	return c.pattern
 }
 
 // Route returns the registered [Route] or nil if the handler is called in a scope other than [RouteHandler].
@@ -342,18 +308,10 @@ func (c *Context) Clone() *Context {
 	cp.rec.ResponseWriter = noopWriter{c.rec.Header().Clone()}
 	cp.w = noUnwrap{&cp.rec}
 
-	subPatterns := make([]string, len(*c.subPatterns))
-	copy(subPatterns, *c.subPatterns)
-	cp.subPatterns = &subPatterns
-
 	params := make([]string, len(*c.params))
 	copy(params, *c.params)
 	cp.params = &params
 
-	keys := make([]string, len(*c.paramsKeys))
-	copy(keys, *c.paramsKeys)
-	cp.paramsKeys = &keys
-
 	return &cp
 }
 
@@ -371,8 +329,6 @@ func (c *Context) CloneWith(w ResponseWriter, r *http.Request) *Context {
 	cp.pattern = c.pattern
 	cp.cachedQueries = nil // For safety, in case r is a different request than c.req
 
-	copyWithResize(cp.subPatterns, c.subPatterns)
-	copyWithResize(cp.paramsKeys, c.paramsKeys)
 	copyWithResize(cp.params, c.params)
 
 	return cp
@@ -513,11 +469,3 @@ func (mw wrapM) handle(c *Context) {
 		mw.next(cc)
 	})).ServeHTTP(flusherWriter{c.Writer()}, r)
 }
-
-func sumLen(s []string) int {
-	var n int
-	for _, v := range s {
-		n += len(v)
-	}
-	return n
-}

context_test.go

@@ -493,7 +493,6 @@ func TestWrapF(t *testing.T) {
 			rte, err := f.NewRoute(MethodGet, "/{foo}", emptyHandler)
 			require.NoError(t, err)
 			c.route = rte
-			*c.paramsKeys = rte.params
 
 			params := make(Params, 0)
 			if tc.params != nil {
@@ -561,7 +560,6 @@ func TestWrapH(t *testing.T) {
 			rte, err := f.NewRoute(MethodGet, "/{foo}", emptyHandler)
 			require.NoError(t, err)
 			c.route = rte
-			*c.paramsKeys = rte.params
 
 			params := make(Params, 0)
 			if tc.params != nil {