rotate patterns; add disjoint shortcut to comparePaths

pattern.go

@@ -310,6 +310,9 @@ func (p1 *Pattern) compareMethods(p2 *Pattern) relationship {
 //	overlaps: there is a path that both match, but neither is more specific
 //	disjoint: there is no path that both match
 func (p1 *Pattern) comparePaths(p2 *Pattern) relationship {
+	if len(p1.segments) != len(p2.segments) && !p1.isMulti() && !p2.isMulti() {
+		return disjoint
+	}
 	// Track whether a single (non-multi) wildcard in p1 matched
 	// a literal in p2, and vice versa.
 	// We care about these because if a wildcard matches a literal, then the

register-disjoint-shortcut-rotated-pat.bench

@@ -0,0 +1,30 @@
+goos: linux
+goarch: amd64
+pkg: github.com/jba/muxpatterns
+cpu: Intel(R) Xeon(R) CPU @ 2.20GHz
+BenchmarkRegister-8   	       1	1192955135 ns/op
+--- BENCH: BenchmarkRegister-8
+    server_test.go:145: benchmarking with 5200 patterns
+    server_test.go:160: conflict calls: 13517400
+BenchmarkRegister-8   	       1	1203853379 ns/op
+--- BENCH: BenchmarkRegister-8
+    server_test.go:145: benchmarking with 5200 patterns
+    server_test.go:160: conflict calls: 13517400
+BenchmarkRegister-8   	       1	1161608161 ns/op
+--- BENCH: BenchmarkRegister-8
+    server_test.go:145: benchmarking with 5200 patterns
+    server_test.go:160: conflict calls: 13517400
+BenchmarkRegister-8   	       1	1185815843 ns/op
+--- BENCH: BenchmarkRegister-8
+    server_test.go:145: benchmarking with 5200 patterns
+    server_test.go:160: conflict calls: 13517400
+BenchmarkRegister-8   	       1	1162129242 ns/op
+--- BENCH: BenchmarkRegister-8
+    server_test.go:145: benchmarking with 5200 patterns
+    server_test.go:160: conflict calls: 13517400
+BenchmarkRegister-8   	       1	1193139316 ns/op
+--- BENCH: BenchmarkRegister-8
+    server_test.go:145: benchmarking with 5200 patterns
+    server_test.go:160: conflict calls: 13517400
+PASS
+ok  	github.com/jba/muxpatterns	7.141s

register-disjoint-shortcut.bench

@@ -0,0 +1,48 @@
+goos: linux
+goarch: amd64
+pkg: github.com/jba/muxpatterns
+cpu: Intel(R) Xeon(R) CPU @ 2.20GHz
+BenchmarkRegister-8   	       2	 947193948 ns/op
+--- BENCH: BenchmarkRegister-8
+    server_test.go:144: benchmarking with 5200 patterns
+    server_test.go:154: conflict calls: 13517400
+    server_test.go:144: benchmarking with 5200 patterns
+    server_test.go:154: conflict calls: 13517400
+    server_test.go:154: conflict calls: 13517400
+BenchmarkRegister-8   	       2	 934951642 ns/op
+--- BENCH: BenchmarkRegister-8
+    server_test.go:144: benchmarking with 5200 patterns
+    server_test.go:154: conflict calls: 13517400
+    server_test.go:144: benchmarking with 5200 patterns
+    server_test.go:154: conflict calls: 13517400
+    server_test.go:154: conflict calls: 13517400
+BenchmarkRegister-8   	       2	 940600999 ns/op
+--- BENCH: BenchmarkRegister-8
+    server_test.go:144: benchmarking with 5200 patterns
+    server_test.go:154: conflict calls: 13517400
+    server_test.go:144: benchmarking with 5200 patterns
+    server_test.go:154: conflict calls: 13517400
+    server_test.go:154: conflict calls: 13517400
+BenchmarkRegister-8   	       2	 963159562 ns/op
+--- BENCH: BenchmarkRegister-8
+    server_test.go:144: benchmarking with 5200 patterns
+    server_test.go:154: conflict calls: 13517400
+    server_test.go:144: benchmarking with 5200 patterns
+    server_test.go:154: conflict calls: 13517400
+    server_test.go:154: conflict calls: 13517400
+BenchmarkRegister-8   	       2	 929820226 ns/op
+--- BENCH: BenchmarkRegister-8
+    server_test.go:144: benchmarking with 5200 patterns
+    server_test.go:154: conflict calls: 13517400
+    server_test.go:144: benchmarking with 5200 patterns
+    server_test.go:154: conflict calls: 13517400
+    server_test.go:154: conflict calls: 13517400
+BenchmarkRegister-8   	       2	 934770076 ns/op
+--- BENCH: BenchmarkRegister-8
+    server_test.go:144: benchmarking with 5200 patterns
+    server_test.go:154: conflict calls: 13517400
+    server_test.go:144: benchmarking with 5200 patterns
+    server_test.go:154: conflict calls: 13517400
+    server_test.go:154: conflict calls: 13517400
+PASS
+ok  	github.com/jba/muxpatterns	17.035s

register-rotated-pat.bench

@@ -0,0 +1,30 @@
+goos: linux
+goarch: amd64
+pkg: github.com/jba/muxpatterns
+cpu: Intel(R) Xeon(R) CPU @ 2.20GHz
+BenchmarkRegister-8   	       1	1259945549 ns/op
+--- BENCH: BenchmarkRegister-8
+    server_test.go:145: benchmarking with 5200 patterns
+    server_test.go:160: conflict calls: 13517400
+BenchmarkRegister-8   	       1	1283687262 ns/op
+--- BENCH: BenchmarkRegister-8
+    server_test.go:145: benchmarking with 5200 patterns
+    server_test.go:160: conflict calls: 13517400
+BenchmarkRegister-8   	       1	1277344750 ns/op
+--- BENCH: BenchmarkRegister-8
+    server_test.go:145: benchmarking with 5200 patterns
+    server_test.go:160: conflict calls: 13517400
+BenchmarkRegister-8   	       1	1293561461 ns/op
+--- BENCH: BenchmarkRegister-8
+    server_test.go:145: benchmarking with 5200 patterns
+    server_test.go:160: conflict calls: 13517400
+BenchmarkRegister-8   	       1	1295861943 ns/op
+--- BENCH: BenchmarkRegister-8
+    server_test.go:145: benchmarking with 5200 patterns
+    server_test.go:160: conflict calls: 13517400
+BenchmarkRegister-8   	       1	1295704471 ns/op
+--- BENCH: BenchmarkRegister-8
+    server_test.go:145: benchmarking with 5200 patterns
+    server_test.go:160: conflict calls: 13517400
+PASS
+ok  	github.com/jba/muxpatterns	7.746s

server_test.go

@@ -11,6 +11,7 @@ import (
 	"net/url"
 	"os"
 	"path/filepath"
+	"strings"
 	"testing"
 )
 
@@ -142,6 +143,11 @@ func BenchmarkRegister(b *testing.B) {
 		b.Fatal(scan.Err())
 	}
 	b.Logf("benchmarking with %d patterns", len(patterns))
+	// To make path comparison harder, move API name to the end.
+	for i, p := range patterns {
+		patterns[i] = moveFirstSegmentToEnd(p)
+	}
+
 	b.ResetTimer()
 
 	for i := 0; i < b.N; i++ {
@@ -154,3 +160,19 @@ func BenchmarkRegister(b *testing.B) {
 		b.Logf("conflict calls: %d", mux.conflictCalls.Load())
 	}
 }
+
+func moveFirstSegmentToEnd(pat string) string {
+	method, path, found := strings.Cut(pat, " ")
+	if !found {
+		panic("bad pattern:" + pat)
+	}
+	if len(path) == 0 || path[0] != '/' {
+		panic("bad path: " + path)
+	}
+	first, rest, found := strings.Cut(path[1:], "/")
+	if !found {
+		panic("missing /:" + path[1:])
+	}
+	path = "/" + rest + "/" + first
+	return method + " " + path
+}