seq_test.go

package it

import (
	"iter"
	"testing"

	"github.com/stretchr/testify/assert"
)

func R(stop int) iter.Seq2[int, int] {
	return func(yield func(int, int) bool) {
		for i := 0; i < stop; i++ {
			if !yield(i, i) {
				return
			}
		}
	}
}

func TestCollect(t *testing.T) {
	r := R(4)
	assert.Equal(t, []Pair[int, int]{{0, 0}, {1, 1}, {2, 2}, {3, 3}}, Collect2(r))
}

func TestNext(t *testing.T) {
	r := Range(4)
	v, ok := Next(r)
	assert.Equal(t, 0, v)
	assert.True(t, ok)

	r = RangeFrom(2, 1)
	v, ok = Next(r)
	assert.Equal(t, 2, v)
	assert.True(t, ok)
}

func TestNth(t *testing.T) {
	r := Range(4)
	v, ok := Nth(r, 2)
	assert.Equal(t, 2, v)
	assert.True(t, ok)

	r = RangeFrom(2, 1)
	v, ok = Nth(r, 2)
	assert.Equal(t, 4, v)
	assert.True(t, ok)

	r = Range(0)
	v, ok = Nth(r, 2)
	assert.Equal(t, 0, v)
	assert.False(t, ok)
}

func TestLast(t *testing.T) {
	r := Range(4)
	v, ok := Last(r)
	assert.Equal(t, 3, v)
	assert.True(t, ok)

	r = Range(0)
	v, ok = Last(r)
	assert.Equal(t, 0, v)
	assert.False(t, ok)
}

func TestCount(t *testing.T) {
	r := Range(10)
	assert.Equal(t, 10, Count(r))
	assert.Equal(t, 0, Count(r))

	r = Range(0)
	assert.Equal(t, 0, Count(r))

	r = Range(-1)
	assert.Equal(t, 0, Count(r))
}

func TestCount2(t *testing.T) {
	r := Enumerate(Range(10))
	assert.Equal(t, 10, Count2(r))
	assert.Equal(t, 0, Count2(r))
}

func TestForEach(t *testing.T) {
	r := Range(4)
	tot := 0
	ForEach(r, func(v int) { tot += v })
	assert.Equal(t, 6, tot)
}

func TestAll(t *testing.T) {
	assert.True(t, All(Range(4), func(v int) bool { return v < 4 }))
	assert.False(t, All(Range(4), func(v int) bool { return v < 3 }))
}

func TestAny(t *testing.T) {
	assert.True(t, Any(Range(4), func(v int) bool { return v == 2 }))
	assert.False(t, Any(Range(4), func(v int) bool { return v == 4 }))
}