package com.mikebull94.result import com.natpryce.hamkrest.Matcher import com.natpryce.hamkrest.assertion.assertThat import com.natpryce.hamkrest.equalTo import com.natpryce.hamkrest.sameInstance import org.junit.jupiter.api.Test internal class IterableTest { private sealed class IterableError { object IterableError1 : IterableError() object IterableError2 : IterableError() } private fun sameError(error: IterableError): Matcher { return sameInstance(error) } @Test internal fun `fold should return the accumulated value if ok`() { val result = listOf(20, 30, 40, 50).fold( initial = 10, operation = { a, b -> ok(a + b) } ) result as Ok assertThat(result.value, equalTo(150)) } @Test internal fun `fold should return the first error if not ok`() { val result: Result = listOf(5, 10, 15, 20, 25).fold( initial = 1, operation = { a, b -> when (b) { (5 + 10) -> err(IterableError.IterableError1) (5 + 10 + 15 + 20) -> err(IterableError.IterableError2) else -> ok(a * b) } } ) result as Error val matcher: Matcher = sameInstance(IterableError.IterableError1) assertThat(result.error, matcher) } @Test internal fun `foldRight should return the accumulated value if ok`() { val result = listOf(2, 5, 10, 20).foldRight( initial = 100, operation = { a, b -> ok(b - a) } ) result as Ok assertThat(result.value, equalTo(63)) } @Test internal fun `foldRight should return the last error if not ok`() { val result = listOf(2, 5, 10, 20, 40).foldRight( initial = 38500, operation = { a, b -> when (b) { (((38500 / 40) / 20) / 10) -> err(IterableError.IterableError1) ((38500 / 40) / 20) -> err(IterableError.IterableError2) else -> ok(b / a) } } ) result as Error assertThat(result.error, sameError(IterableError.IterableError2)) } @Test internal fun `combine should return the combined list of values if results are ok`() { val values = combine( ok(10), ok(20), ok(30) ).get()!! assertThat(values.size, equalTo(3)) assertThat(values[0], equalTo(10)) assertThat(values[1], equalTo(20)) assertThat(values[2], equalTo(30)) } @Test internal fun `combine should return the first error if results are not ok`() { val result = combine( ok(20), ok(40), err(IterableError.IterableError1), ok(60), err(IterableError.IterableError2), ok(80) ) result as Error assertThat(result.error, sameError(IterableError.IterableError1)) } @Test internal fun `getAll should return all of the result values`() { val values = getAll( ok("hello"), ok("big"), err(IterableError.IterableError2), ok("wide"), err(IterableError.IterableError1), ok("world") ) assertThat(values.size, equalTo(4)) assertThat(values[0], equalTo("hello")) assertThat(values[1], equalTo("big")) assertThat(values[2], equalTo("wide")) assertThat(values[3], equalTo("world")) } @Test internal fun `getAllErrors should return all of the result errors`() { val errors = getAllErrors( err(IterableError.IterableError2), ok("haskell"), err(IterableError.IterableError2), ok("f#"), err(IterableError.IterableError1), ok("elm"), err(IterableError.IterableError1), ok("clojure"), err(IterableError.IterableError2) ) assertThat(errors.size, equalTo(5)) assertThat(errors[0], sameError(IterableError.IterableError2)) assertThat(errors[1], sameError(IterableError.IterableError2)) assertThat(errors[2], sameError(IterableError.IterableError1)) assertThat(errors[3], sameError(IterableError.IterableError1)) assertThat(errors[4], sameError(IterableError.IterableError2)) } @Test internal fun `partition should return a pair of all the result values and errors`() { val pairs = partition( err(IterableError.IterableError2), ok("haskell"), err(IterableError.IterableError2), ok("f#"), err(IterableError.IterableError1), ok("elm"), err(IterableError.IterableError1), ok("clojure"), err(IterableError.IterableError2) ) val values = pairs.first assertThat(values.size, equalTo(4)) assertThat(values[0], equalTo("haskell")) assertThat(values[1], equalTo("f#")) assertThat(values[2], equalTo("elm")) assertThat(values[3], equalTo("clojure")) val errors = pairs.second assertThat(errors.size, equalTo(5)) assertThat(errors[0], sameError(IterableError.IterableError2)) assertThat(errors[1], sameError(IterableError.IterableError2)) assertThat(errors[2], sameError(IterableError.IterableError1)) assertThat(errors[3], sameError(IterableError.IterableError1)) assertThat(errors[4], sameError(IterableError.IterableError2)) } }