| // Copyright 2014 The Go Authors. All rights reserved. |
| // Use of this source code is governed by a BSD-style |
| // license that can be found in the LICENSE file. |
| |
| package triegen_test |
| |
| import ( |
| "fmt" |
| "io" |
| "math/rand" |
| "unicode" |
| |
| "golang.org/x/text/internal/triegen" |
| ) |
| |
| const seed = 0x12345 |
| |
| var genWriter = io.Discard |
| |
| func randomRunes() map[rune]uint8 { |
| rnd := rand.New(rand.NewSource(seed)) |
| m := map[rune]uint8{} |
| for len(m) < 100 { |
| // Only set our random rune if it is a valid Unicode code point. |
| if r := rune(rnd.Int31n(unicode.MaxRune + 1)); []rune(string(r))[0] == r { |
| m[r] = 1 |
| } |
| } |
| return m |
| } |
| |
| // Example_build shows how to build a simple trie. It assigns the value 1 to |
| // 100 random runes generated by randomRunes. |
| func Example_build() { |
| t := triegen.NewTrie("rand") |
| |
| for r, _ := range randomRunes() { |
| t.Insert(r, 1) |
| } |
| sz, err := t.Gen(genWriter) |
| |
| fmt.Printf("Trie size: %d bytes\n", sz) |
| fmt.Printf("Error: %v\n", err) |
| |
| // Output: |
| // Trie size: 9280 bytes |
| // Error: <nil> |
| } |
| |
| // Example_lookup demonstrates how to use the trie generated by Example_build. |
| func Example_lookup() { |
| trie := newRandTrie(0) |
| |
| // The same set of runes used by Example_build. |
| runes := randomRunes() |
| |
| // Verify the right value is returned for all runes. |
| for r := rune(0); r <= unicode.MaxRune; r++ { |
| // Note that the return type of lookup is uint8. |
| if v, _ := trie.lookupString(string(r)); v != runes[r] { |
| fmt.Println("FAILURE") |
| return |
| } |
| } |
| fmt.Println("SUCCESS") |
| |
| // Output: |
| // SUCCESS |
| } |
| |
| // runeValues generates some random values for a set of interesting runes. |
| func runeValues() map[rune]uint64 { |
| rnd := rand.New(rand.NewSource(seed)) |
| m := map[rune]uint64{} |
| for p := 4; p <= unicode.MaxRune; p <<= 1 { |
| for d := -1; d <= 1; d++ { |
| m[rune(p+d)] = uint64(rnd.Int63()) |
| } |
| } |
| return m |
| } |
| |
| // ExampleGen_build demonstrates the creation of multiple tries sharing common |
| // blocks. ExampleGen_lookup demonstrates how to use the generated tries. |
| func ExampleGen_build() { |
| var tries []*triegen.Trie |
| |
| rv := runeValues() |
| for _, c := range []struct { |
| include func(rune) bool |
| name string |
| }{ |
| {func(r rune) bool { return true }, "all"}, |
| {func(r rune) bool { return r < 0x80 }, "ASCII only"}, |
| {func(r rune) bool { return r < 0x80 }, "ASCII only 2"}, |
| {func(r rune) bool { return r <= 0xFFFF }, "BMP only"}, |
| {func(r rune) bool { return r > 0xFFFF }, "No BMP"}, |
| } { |
| t := triegen.NewTrie(c.name) |
| tries = append(tries, t) |
| |
| for r, v := range rv { |
| if c.include(r) { |
| t.Insert(r, v) |
| } |
| } |
| } |
| sz, err := triegen.Gen(genWriter, "multi", tries) |
| |
| fmt.Printf("Trie size: %d bytes\n", sz) |
| fmt.Printf("Error: %v\n", err) |
| |
| // Output: |
| // Trie size: 18250 bytes |
| // Error: <nil> |
| } |
| |
| // ExampleGen_lookup shows how to look up values in the trie generated by |
| // ExampleGen_build. |
| func ExampleGen_lookup() { |
| rv := runeValues() |
| for i, include := range []func(rune) bool{ |
| func(r rune) bool { return true }, // all |
| func(r rune) bool { return r < 0x80 }, // ASCII only |
| func(r rune) bool { return r < 0x80 }, // ASCII only 2 |
| func(r rune) bool { return r <= 0xFFFF }, // BMP only |
| func(r rune) bool { return r > 0xFFFF }, // No BMP |
| } { |
| t := newMultiTrie(i) |
| |
| for r := rune(0); r <= unicode.MaxRune; r++ { |
| x := uint64(0) |
| if include(r) { |
| x = rv[r] |
| } |
| // As we convert from a valid rune, we know it is safe to use |
| // lookupStringUnsafe. |
| if v := t.lookupStringUnsafe(string(r)); x != v { |
| fmt.Println("FAILURE") |
| return |
| } |
| } |
| } |
| fmt.Println("SUCCESS") |
| |
| // Output: |
| // SUCCESS |
| } |