stdlib: Add insert methods in StringBuilder

2017-04-19 16:50:52 +07:00
parent f2fd80e9e3
commit 9607033c11
3 changed files with 244 additions and 1 deletions
@@ -0,0 +1,136 @@
+fun assertEquals(builder: StringBuilder, content: String) {
+    if (builder.toString() != content) throw AssertionError("Test failed: " + builder.toString() + " != " + content)
+}
+
+fun assertTrue(condition: Boolean) {
+    if (!condition) throw AssertionError("The condition is false")
+}
+
+// IndexOutOfBoundsException
+fun assertException(body: () -> Unit) {
+    try {
+        body()
+        throw AssertionError ("Test failed: no IndexOutOfBoundsException on wrong indices")
+    } catch (e: IndexOutOfBoundsException) {}
+}
+
+fun String.toCharArray(): CharArray = CharArray(length) { i -> this[i] }
+
+fun testInsertString(initial: String, index: Int, toInsert: String, expected: String) {
+    assertEquals(StringBuilder(initial).insert(index, toInsert),                 expected)
+    assertEquals(StringBuilder(initial).insert(index, toInsert.toCharArray()),   expected)
+    assertEquals(StringBuilder(initial).insert(index, toInsert as CharSequence), expected)
+}
+
+fun testInsertStringException(initial: String, index: Int, toInsert: String) {
+    assertException { StringBuilder(initial).insert(index, toInsert) }
+    assertException { StringBuilder(initial).insert(index, toInsert.toCharArray()) }
+    assertException { StringBuilder(initial).insert(index, toInsert as CharSequence) }
+}
+
+fun testInsertSingle(value: Byte) {
+    assertEquals(StringBuilder("abcd").insert(0, value),  value.toString() + "abcd")
+    assertEquals(StringBuilder("abcd").insert(4, value),  "abcd" + value.toString())
+    assertEquals(StringBuilder("abcd").insert(2, value),  "ab" + value.toString() + "cd")
+    assertEquals(StringBuilder("").insert(0, value),      value.toString())
+}
+
+fun testInsertSingle(value: Short) {
+    assertEquals(StringBuilder("abcd").insert(0, value),  value.toString() + "abcd")
+    assertEquals(StringBuilder("abcd").insert(4, value),  "abcd" + value.toString())
+    assertEquals(StringBuilder("abcd").insert(2, value),  "ab" + value.toString() + "cd")
+    assertEquals(StringBuilder("").insert(0, value),      value.toString())
+}
+
+fun testInsertSingle(value: Int) {
+    assertEquals(StringBuilder("abcd").insert(0, value),  value.toString() + "abcd")
+    assertEquals(StringBuilder("abcd").insert(4, value),  "abcd" + value.toString())
+    assertEquals(StringBuilder("abcd").insert(2, value),  "ab" + value.toString() + "cd")
+    assertEquals(StringBuilder("").insert(0, value),      value.toString())
+}
+
+fun testInsertSingle(value: Long) {
+    assertEquals(StringBuilder("abcd").insert(0, value),  value.toString() + "abcd")
+    assertEquals(StringBuilder("abcd").insert(4, value),  "abcd" + value.toString())
+    assertEquals(StringBuilder("abcd").insert(2, value),  "ab" + value.toString() + "cd")
+    assertEquals(StringBuilder("").insert(0, value),      value.toString())
+}
+
+fun testInsertSingle(value: Float) {
+    assertEquals(StringBuilder("abcd").insert(0, value),  value.toString() + "abcd")
+    assertEquals(StringBuilder("abcd").insert(4, value),  "abcd" + value.toString())
+    assertEquals(StringBuilder("abcd").insert(2, value),  "ab" + value.toString() + "cd")
+    assertEquals(StringBuilder("").insert(0, value),      value.toString())
+}
+
+fun testInsertSingle(value: Double) {
+    assertEquals(StringBuilder("abcd").insert(0, value),  value.toString() + "abcd")
+    assertEquals(StringBuilder("abcd").insert(4, value),  "abcd" + value.toString())
+    assertEquals(StringBuilder("abcd").insert(2, value),  "ab" + value.toString() + "cd")
+    assertEquals(StringBuilder("").insert(0, value),      value.toString())
+}
+
+fun testInsertSingle(value: Any?) {
+    assertEquals(StringBuilder("abcd").insert(0, value),  value.toString() + "abcd")
+    assertEquals(StringBuilder("abcd").insert(4, value),  "abcd" + value.toString())
+    assertEquals(StringBuilder("abcd").insert(2, value),  "ab" + value.toString() + "cd")
+    assertEquals(StringBuilder("").insert(0, value),      value.toString())
+}
+
+fun testInsertSingle(value: Char) {
+    assertEquals(StringBuilder("abcd").insert(0, value),  value.toString() + "abcd")
+    assertEquals(StringBuilder("abcd").insert(4, value),  "abcd" + value.toString())
+    assertEquals(StringBuilder("abcd").insert(2, value),  "ab" + value.toString() + "cd")
+    assertEquals(StringBuilder("").insert(0, value),      value.toString())
+}
+
+fun main(args: Array<String>) {
+    // String/CharSequence/CharArray
+    testInsertString("abcd", 0, "12", "12abcd")
+    testInsertString("abcd", 4, "12", "abcd12")
+    testInsertString("abcd", 2, "12", "ab12cd")
+    testInsertString("", 0, "12", "12")
+    testInsertStringException("a", -1, "1")
+    testInsertStringException("a", 2, "1")
+
+    // Subsequence of CharSequence
+    // Insert in the beginning
+    assertEquals(StringBuilder("abcd").insert(0, "1234", 0, 0), "abcd")     // 0 symbols
+    assertEquals(StringBuilder("abcd").insert(0, "1234", 0, 1), "1abcd")    // 1 symbol
+    assertEquals(StringBuilder("abcd").insert(0, "1234", 1, 3), "23abcd")   // 2 symbols
+
+    // Insert in the end
+    assertEquals(StringBuilder("abcd").insert(4, "1234", 0, 0), "abcd")
+    assertEquals(StringBuilder("abcd").insert(4, "1234", 0, 1), "abcd1")
+    assertEquals(StringBuilder("abcd").insert(4, "1234", 1, 3), "abcd23")
+
+    // Insert in the middle
+    assertEquals(StringBuilder("abcd").insert(2, "1234", 0, 0), "abcd")
+    assertEquals(StringBuilder("abcd").insert(2, "1234", 0, 1), "ab1cd")
+    assertEquals(StringBuilder("abcd").insert(2, "1234", 1, 3), "ab23cd")
+
+    // Incorrect indices
+    assertException { StringBuilder("a").insert(-1, "1", 0, 0) }
+    assertException { StringBuilder("a").insert(2, "1", 0, 0) }
+    assertException { StringBuilder("a").insert(1, "1", -1, 0) }
+    assertException { StringBuilder("a").insert(1, "1", 0, 2) }
+    assertException { StringBuilder("a").insert(1, "123", 2, 0) }
+
+
+    // Other types
+    testInsertSingle(true)
+    testInsertSingle(42.toByte())
+    testInsertSingle(42.toShort())
+    testInsertSingle(42.toInt())
+    testInsertSingle(42.toLong())
+    testInsertSingle(42.2.toFloat())
+    testInsertSingle(42.2.toDouble())
+    testInsertSingle(object {
+        override fun toString(): String {
+            return "Object"
+        }
+    })
+    testInsertSingle('a')
+
+    println("OK")
+}