package main

import (
	"bufio"
	"strings"
	"testing"

	"github.com/google/go-cmp/cmp"
)

func TestSplitTokens(t *testing.T) {
	t.Parallel()

	for _, tc := range []struct {
		desc  string
		input string
		want  []string
	}{{
		desc:  "SingleWord",
		input: "a",
		want:  []string{"a"},
	}, {
		desc:  "SplitWords",
		input: "a b c",
		want:  []string{"a", "b", "c"},
	}, {
		desc:  "Star",
		input: "a*b",
		want:  []string{"a", "", "*", "", "b"},
	}, {
		desc:  "Background",
		input: "a&b",
		want:  []string{"a", "&", "b"},
	}, {
		desc:  "Pipe",
		input: "a|b",
		want:  []string{"a", "|", "b"},
	}, {
		desc:  "And",
		input: "a&&b",
		want:  []string{"a", "&&", "b"},
	}, {
		desc:  "Newline",
		input: "a\n",
		want:  []string{"a", ";"},
	}, {
		desc:  "CaptureOutputAsFile",
		input: "a<(b)",
		want:  []string{"a", "<(", "b", ")"},
	}, {
		desc:  "Substitution",
		input: "a$(b)c",
		want:  []string{"a", "", "$(", "b", ")", "", "c"},
	}, {
		desc:  "Comment",
		input: "abc#de;fg",
		want:  []string{"abc"},
	}, {
		desc:  "CommentNewline",
		input: "a#b\n",
		want:  []string{"a", ";"},
	}, {
		desc:  "BackslashEOF",
		input: `a\`,
		want:  []string{`a\`},
	}} {
		t.Run(tc.desc, func(t *testing.T) {
			scanner := bufio.NewScanner(strings.NewReader(tc.input))
			scanner.Split(splitTokens())
			var got []string
			for scanner.Scan() {
				got = append(got, scanner.Text())
			}
			if err := scanner.Err(); err != nil {
				t.Fatalf("splitTokens failed: %s", err)
			}
			if diff := cmp.Diff(tc.want, got); diff != "" {
				t.Errorf("splitTokens produced unexpected diff (-want +got):\n%s", diff)
			}
		})
	}
}

func FuzzSplitTokens(f *testing.F) {
	testcases := []string{"a", "a b c", "a*b", "a&b", "a|b", "a&&b", "a\n", "a<(b)", "a$(b)c", "abc#de;fg", "a#b\n", `a\`}
	for _, tc := range testcases {
		f.Add([]byte(tc))
	}
	f.Fuzz(func(t *testing.T, input []byte) {
		splitTokens()(input, true)
		splitTokens()(input, false)
	})
}