diff --git a/core-kotlin/src/test/kotlin/com/baeldung/kotlin/stdlib/RegexTest.kt b/core-kotlin/src/test/kotlin/com/baeldung/kotlin/stdlib/RegexTest.kt new file mode 100644 index 0000000000..eeb587ee22 --- /dev/null +++ b/core-kotlin/src/test/kotlin/com/baeldung/kotlin/stdlib/RegexTest.kt @@ -0,0 +1,128 @@ +package com.baeldung.kotlin.stdlib + +import org.junit.Test +import java.beans.ExceptionListener +import java.beans.XMLEncoder +import java.io.* +import java.lang.Exception +import kotlin.test.* +import kotlin.text.RegexOption.* + +class RegexTest { + + @Test + fun whenRegexIsInstantiated_thenIsEqualToToRegexMethod() { + val pattern = """a([bc]+)d?\\""" + + assertEquals(Regex.fromLiteral(pattern).pattern, pattern) + assertEquals(pattern, Regex(pattern).pattern) + assertEquals(pattern, pattern.toRegex().pattern) + } + + @Test + fun whenRegexMatches_thenResultIsTrue() { + val regex = """a([bc]+)d?""".toRegex() + + assertTrue(regex.containsMatchIn("xabcdy")) + assertTrue(regex.matches("abcd")) + assertFalse(regex matches "xabcdy") + } + + @Test + fun givenCompletelyMatchingRegex_whenMatchResult_thenDestructuring() { + val regex = """a([bc]+)d?""".toRegex() + + assertNull(regex.matchEntire("xabcdy")) + + val matchResult = regex.matchEntire("abbccbbd") + + assertNotNull(matchResult) + assertEquals(matchResult!!.value, matchResult.groupValues[0]) + assertEquals(matchResult.destructured.toList(), matchResult.groupValues.drop(1)) + assertEquals("bbccbb", matchResult.destructured.component1()) + assertNull(matchResult.next()) + } + + @Test + fun givenPartiallyMatchingRegex_whenMatchResult_thenGroups() { + val regex = """a([bc]+)d?""".toRegex() + var matchResult = regex.find("abcb abbd") + + assertNotNull(matchResult) + assertEquals(matchResult!!.value, matchResult.groupValues[0]) + assertEquals("abcb", matchResult.value) + assertEquals(IntRange(0, 3), matchResult.range) + assertEquals(listOf("abcb", "bcb"), matchResult.groupValues) + assertEquals(matchResult.destructured.toList(), matchResult.groupValues.drop(1)) + + matchResult = matchResult.next() + + assertNotNull(matchResult) + assertEquals("abbd", matchResult!!.value) + assertEquals("bb", matchResult.groupValues[1]) + + matchResult = matchResult.next() + + assertNull(matchResult) + } + + @Test + fun givenPartiallyMatchingRegex_whenMatchResult_thenDestructuring() { + val regex = """([\w\s]+) is (\d+) years old""".toRegex() + val matchResult = regex.find("Mickey Mouse is 95 years old") + val (name, age) = matchResult!!.destructured + + assertEquals("Mickey Mouse", name) + assertEquals("95", age) + } + + @Test + fun givenNonMatchingRegex_whenFindCalled_thenNull() { + val regex = """a([bc]+)d?""".toRegex() + val matchResult = regex.find("foo") + + assertNull(matchResult) + } + + @Test + fun givenNonMatchingRegex_whenFindAllCalled_thenEmptySet() { + val regex = """a([bc]+)d?""".toRegex() + val matchResults = regex.findAll("foo") + + assertNotNull(matchResults) + assertTrue(matchResults.none()) + } + + @Test + fun whenReplace_thenReplacement() { + val regex = """(red|green|blue)""".toRegex() + val beautiful = "Roses are red, Violets are blue" + val grim = regex.replace(beautiful, "dark") + val shiny = regex.replaceFirst(beautiful, "rainbow") + + assertEquals("Roses are dark, Violets are dark", grim) + assertEquals("Roses are rainbow, Violets are blue", shiny) + } + + @Test + fun whenComplexReplace_thenReplacement() { + val regex = """(red|green|blue)""".toRegex() + val beautiful = "Roses are red, Violets are blue" + val reallyBeautiful = regex.replace(beautiful) { + matchResult -> matchResult.value.toUpperCase() + "!" + } + + assertEquals("Roses are RED!, Violets are BLUE!", reallyBeautiful) + } + + @Test + fun whenSplit_thenList() { + val regex = """\W+""".toRegex() + val beautiful = "Roses are red, Violets are blue" + + assertEquals(listOf("Roses", "are", "red", "Violets", "are", "blue"), regex.split(beautiful)) + assertEquals(listOf("Roses", "are", "red", "Violets are blue"), regex.split(beautiful, 4)) + assertEquals(regex.toPattern().split(beautiful).asList(), regex.split(beautiful)) + } + +} \ No newline at end of file