Update comments and benchmarks after 1 allocation optimization, thanks …

…@bouk

README.md

@@ -430,25 +430,25 @@ and..
 
 The benchmark suite: https://github.com/pkieltyka/go-http-routing-benchmark
 
-Results as of Jan 9, 2019 with Go 1.11.4 on Linux X1 Carbon laptop
+Results as of Nov 29, 2020 with Go 1.15.5 on Linux AMD 3950x
 
 ```shell
-BenchmarkChi_Param            3000000         475 ns/op       432 B/op      3 allocs/op
-BenchmarkChi_Param5           2000000         696 ns/op       432 B/op      3 allocs/op
-BenchmarkChi_Param20          1000000        1275 ns/op       432 B/op      3 allocs/op
-BenchmarkChi_ParamWrite       3000000         505 ns/op       432 B/op      3 allocs/op
-BenchmarkChi_GithubStatic     3000000         508 ns/op       432 B/op      3 allocs/op
-BenchmarkChi_GithubParam      2000000         669 ns/op       432 B/op      3 allocs/op
-BenchmarkChi_GithubAll          10000      134627 ns/op     87699 B/op    609 allocs/op
-BenchmarkChi_GPlusStatic      3000000         402 ns/op       432 B/op      3 allocs/op
-BenchmarkChi_GPlusParam       3000000         500 ns/op       432 B/op      3 allocs/op
-BenchmarkChi_GPlus2Params     3000000         586 ns/op       432 B/op      3 allocs/op
-BenchmarkChi_GPlusAll          200000        7237 ns/op      5616 B/op     39 allocs/op
-BenchmarkChi_ParseStatic      3000000         408 ns/op       432 B/op      3 allocs/op
-BenchmarkChi_ParseParam       3000000         488 ns/op       432 B/op      3 allocs/op
-BenchmarkChi_Parse2Params     3000000         551 ns/op       432 B/op      3 allocs/op
-BenchmarkChi_ParseAll          100000       13508 ns/op     11232 B/op     78 allocs/op
-BenchmarkChi_StaticAll          20000       81933 ns/op     67826 B/op    471 allocs/op
+BenchmarkChi_Param          	3075895	        384 ns/op	      400 B/op      2 allocs/op
+BenchmarkChi_Param5         	2116603	        566 ns/op	      400 B/op      2 allocs/op
+BenchmarkChi_Param20        	 964117	       1227 ns/op	      400 B/op      2 allocs/op
+BenchmarkChi_ParamWrite     	2863413	        420 ns/op	      400 B/op      2 allocs/op
+BenchmarkChi_GithubStatic   	3045488	        395 ns/op	      400 B/op      2 allocs/op
+BenchmarkChi_GithubParam    	2204115	        540 ns/op	      400 B/op      2 allocs/op
+BenchmarkChi_GithubAll      	  10000	     113811 ns/op	    81203 B/op    406 allocs/op
+BenchmarkChi_GPlusStatic    	3337485	        359 ns/op	      400 B/op      2 allocs/op
+BenchmarkChi_GPlusParam     	2825853	        423 ns/op	      400 B/op      2 allocs/op
+BenchmarkChi_GPlus2Params   	2471697	        483 ns/op	      400 B/op      2 allocs/op
+BenchmarkChi_GPlusAll       	 194220	       5950 ns/op	     5200 B/op     26 allocs/op
+BenchmarkChi_ParseStatic    	3365324	        356 ns/op	      400 B/op      2 allocs/op
+BenchmarkChi_ParseParam     	2976614	        404 ns/op	      400 B/op      2 allocs/op
+BenchmarkChi_Parse2Params   	2638084	        439 ns/op	      400 B/op      2 allocs/op
+BenchmarkChi_ParseAll       	 109567	      11295 ns/op	    10400 B/op     52 allocs/op
+BenchmarkChi_StaticAll      	  16846	      71308 ns/op	    62802 B/op    314 allocs/op
 ```
 
 Comparison with other routers: https://gist.github.com/pkieltyka/123032f12052520aaccab752bd3e78cc

context.go

@@ -94,7 +94,9 @@ type Context struct {
 	// methodNotAllowed hint
 	methodNotAllowed bool
 
-	// parentCtx is the parent of this one, for using Context as a context.Context directly
+	// parentCtx is the parent of this one, for using Context as a
+	// context.Context directly. This is an optimization that saves
+	// 1 allocation.
 	parentCtx context.Context
 }
 
@@ -111,6 +113,7 @@ func (x *Context) Reset() {
 	x.routeParams.Keys = x.routeParams.Keys[:0]
 	x.routeParams.Values = x.routeParams.Values[:0]
 	x.methodNotAllowed = false
+	x.parentCtx = nil
 }
 
 // URLParam returns the corresponding URL parameter value from the request
@@ -143,6 +146,30 @@ func (x *Context) RoutePattern() string {
 	return replaceWildcards(routePattern)
 }
 
+// replaceWildcards takes a route pattern and recursively replaces all
+// occurrences of "/*/" to "/".
+func replaceWildcards(p string) string {
+	if strings.Contains(p, "/*/") {
+		return replaceWildcards(strings.Replace(p, "/*/", "/", -1))
+	}
+
+	return p
+}
+
+// RouteParams is a structure to track URL routing parameters efficiently.
+type RouteParams struct {
+	Keys, Values []string
+}
+
+// Add will append a URL parameter to the end of the route param
+func (s *RouteParams) Add(key, value string) {
+	s.Keys = append(s.Keys, key)
+	s.Values = append(s.Values, value)
+}
+
+// directContext provides direct access to the routing *Context object,
+// while implementing the context.Context interface, thereby allowing
+// us to saving 1 allocation during routing.
 type directContext Context
 
 var _ context.Context = (*directContext)(nil)
@@ -166,27 +193,6 @@ func (d *directContext) Value(key interface{}) interface{} {
 	return d.parentCtx.Value(key)
 }
 
-// replaceWildcards takes a route pattern and recursively replaces all
-// occurrences of "/*/" to "/".
-func replaceWildcards(p string) string {
-	if strings.Contains(p, "/*/") {
-		return replaceWildcards(strings.Replace(p, "/*/", "/", -1))
-	}
-
-	return p
-}
-
-// RouteParams is a structure to track URL routing parameters efficiently.
-type RouteParams struct {
-	Keys, Values []string
-}
-
-// Add will append a URL parameter to the end of the route param
-func (s *RouteParams) Add(key, value string) {
-	s.Keys = append(s.Keys, key)
-	s.Values = append(s.Values, value)
-}
-
 // contextKey is a value for use with context.WithValue. It's used as
 // a pointer so it fits in an interface{} without allocation. This technique
 // for defining context keys was copied from Go 1.7's new use of context in net/http.