Add benchmarks (#17)

Author: cristaloleg

GUIDE.md

@@ -31,3 +31,20 @@ Both `%$` and `%?` formats can be extended with `+` or `#`:
 * `%#?` will expand slice of slices argument as `(?, ?), (?, ?), ... (?, ?)`
 
 Argument must be a slice (for `+`) or a slice of slices (for `#`), otherwise the `.Build()` method returns an error.
+
+## Speed
+
+Even with the `fmt` packge speed is very good. If case you want zero-allocation query builder consider to cache query and just use it's value (works only for static queries like in `BenchmarkBuildCached`)
+
+```
+goos: darwin
+goarch: arm64
+pkg: github.com/cristalhq/builq
+BenchmarkBuildNaive
+BenchmarkBuildNaive-10       	  299349	      4214 ns/op	     488 B/op	       8 allocs/op
+BenchmarkBuildManyArgs
+BenchmarkBuildManyArgs-10    	   85747	     14027 ns/op	    1056 B/op	      24 allocs/op
+BenchmarkBuildCached
+BenchmarkBuildCached-10      	1000000000	         0.6213 ns/op	       0 B/op	       0 allocs/op
+PASS
+```

README.md

@@ -17,7 +17,7 @@ This tiny library helps to build queries and handles parameter indexing.
 ## Features
 
 * Simple and easy.
-* Safe.
+* Safe & fast.
 * Tested.
 * Dependency-free.
 

builq.go

@@ -35,14 +35,23 @@ func (b *Builder) Addf(format string, args ...any) *Builder {
 	if b.err != nil {
 		return b
 	}
+	// prealloc on first Addf
+	if b.args == nil {
+		b.query.Grow(100)
+		b.args = make([]any, 0, 10)
+	}
 
 	wargs := make([]any, len(args))
-	for i, arg := range args {
-		wargs[i] = &argument{value: arg, builder: b}
+	for i := range args {
+		wargs[i] = &argument{value: args[i], builder: b}
 	}
 
-	fmt.Fprintf(&b.query, format+"\n", wargs...)
+	_, err := fmt.Fprintf(&b.query, format, wargs...)
+	if b.err == nil && err != nil {
+		b.err = err
+	}
 
+	b.query.WriteByte('\n')
 	return b
 }
 

builq_bench_test.go

@@ -0,0 +1,73 @@
+package builq_test
+
+import (
+	"testing"
+
+	"github.com/cristalhq/builq"
+)
+
+func BenchmarkBuildNaive(b *testing.B) {
+	for i := 0; i < b.N; i++ {
+		var bb builq.Builder
+		bb.Addf("SELECT %s FROM %s", "foo,bar", "table")
+		bb.Addf("WHERE id = %$", 123)
+		query, args, err := bb.Build()
+
+		switch {
+		case err != nil:
+			b.Fatal(err)
+		case len(query) == 0:
+			b.Fatal("empty query")
+		case len(args) == 0:
+			b.Fatal("empty args")
+		}
+	}
+}
+
+func BenchmarkBuildManyArgs(b *testing.B) {
+	for i := 0; i < b.N; i++ {
+		var bb builq.Builder
+		bb.Addf("SELECT %s FROM %s", "foo,bar", "table")
+		bb.Addf("WHERE id = %$", 123)
+		bb.Addf("AND user_id = %$ OR referral_id = %$", 123, 456)
+		bb.Addf("OR status = %$ OR name = %$", "admin", "nice")
+		bb.Addf("AND password LIKE %$ OR password = %$", "str0ng", "qwerty")
+		bb.Addf("GROUP BY %$", "foo")
+		bb.Addf("ORDER BY %$", "bar")
+		bb.Addf("LIMIT %$;", 123)
+		query, args, err := bb.Build()
+
+		switch {
+		case err != nil:
+			b.Fatal(err)
+		case len(query) == 0:
+			b.Fatal("empty query")
+		case len(args) == 0:
+			b.Fatal("empty args")
+		}
+	}
+}
+
+func BenchmarkBuildCached(b *testing.B) {
+	var bb builq.Builder
+	bb.Addf("SELECT %s FROM %s", "foo,bar", "table")
+	bb.Addf("WHERE id = %$", 123)
+	bb.Addf("AND user_id = %$ OR referral_id = %$", 123, 456)
+	bb.Addf("OR status = %$ OR name = %$", "admin", "nice")
+	bb.Addf("GROUP BY %$", "foo")
+	bb.Addf("ORDER BY %$", "bar")
+	bb.Addf("LIMIT %$;", 123)
+	query, args, err := bb.Build()
+	b.ResetTimer()
+
+	for i := 0; i < b.N; i++ {
+		switch {
+		case err != nil:
+			b.Fatal(err)
+		case len(query) == 0:
+			b.Fatal("empty query")
+		case len(args) == 0:
+			b.Fatal("empty args")
+		}
+	}
+}