// sample-wordcount_test.go: tests for sample-wordcount.go.
// Free sample from 99helpers.com/file-types/go
//
// Files ending in _test.go are only compiled by `go test`, never by
// `go build`. Run the tests (and the example) with:
//
//	go test -v sample-wordcount.go sample-wordcount_test.go
//
// and the benchmark (b.Loop needs Go 1.24 or later) with:
//
//	go test -bench=. sample-wordcount.go sample-wordcount_test.go
package main

import (
	"fmt"
	"maps"
	"strings"
	"testing"
)

// A test function: its name starts with Test and it takes a *testing.T.
// This one is table-driven: each case is a row, run as a named subtest.
func TestCountWords(t *testing.T) {
	cases := []struct {
		name string
		text string
		want map[string]int
	}{
		{"empty", "", map[string]int{}},
		{"case folding", "Go go GO", map[string]int{"go": 3}},
		{"punctuation", "one, two; two!", map[string]int{"one": 1, "two": 2}},
		{"accents", "Café CAFÉ café", map[string]int{"café": 3}},
		{"German", "Straße straße", map[string]int{"straße": 2}},
		{"Japanese", "東京 大阪 東京", map[string]int{"東京": 2, "大阪": 1}},
		{"digits", "route 66, route 66", map[string]int{"route": 2, "66": 2}},
	}
	for _, tc := range cases {
		t.Run(tc.name, func(t *testing.T) {
			got := CountWords(tc.text)
			if !maps.Equal(got, tc.want) {
				t.Errorf("CountWords(%q) = %v, want %v", tc.text, got, tc.want)
			}
		})
	}
}

func TestTopWordsTies(t *testing.T) {
	got := TopWords(map[string]int{"b": 2, "a": 2, "c": 5}, 2)
	want := []WordCount{{"c", 5}, {"a", 2}}
	if fmt.Sprint(got) != fmt.Sprint(want) {
		t.Errorf("TopWords = %v, want %v", got, want)
	}
}

// An example: go test runs it and compares what it prints with the
// "Output:" comment. It also appears in the package's documentation.
func ExampleTopWords() {
	counts := CountWords("to be or not to be")
	fmt.Println(TopWords(counts, 2))
	// Output: [{be 2} {to 2}]
}

// A benchmark: go test -bench=. runs the loop as many times as it needs to
// measure it.
func BenchmarkCountWords(b *testing.B) {
	text := strings.Repeat("the quick brown fox jumps over the lazy dog ", 100)
	for b.Loop() {
		CountWords(text)
	}
}