From ea71808f40d9add7a31ab152055b8b98570ca5fd Mon Sep 17 00:00:00 2001
From: sorellla <martinemarrelli@gmail.com>
Date: Wed, 17 Sep 2025 19:58:36 +0200
Subject: [PATCH] #128: add cutOff function

---
 src/main/kotlin/utils/StringUtils.kt       |  6 ++++
 src/test/kotlin/utils/StringUtilsKtTest.kt | 42 ++++++++++++++++++++++
 2 files changed, 48 insertions(+)
 create mode 100644 src/main/kotlin/utils/StringUtils.kt
 create mode 100644 src/test/kotlin/utils/StringUtilsKtTest.kt

diff --git a/src/main/kotlin/utils/StringUtils.kt b/src/main/kotlin/utils/StringUtils.kt
new file mode 100644
index 0000000..0518fa0
--- /dev/null
+++ b/src/main/kotlin/utils/StringUtils.kt
@@ -0,0 +1,6 @@
+package utils
+
+fun String.cutOff(maxCharsPerLine: Int): String {
+    require(maxCharsPerLine > 0) { "Character limit should be at least 1" }
+    return if (length <= maxCharsPerLine) this else "${take(maxCharsPerLine - 1)}…"
+}
diff --git a/src/test/kotlin/utils/StringUtilsKtTest.kt b/src/test/kotlin/utils/StringUtilsKtTest.kt
new file mode 100644
index 0000000..81f9eca
--- /dev/null
+++ b/src/test/kotlin/utils/StringUtilsKtTest.kt
@@ -0,0 +1,42 @@
+package utils
+
+import io.kotest.assertions.throwables.shouldThrow
+import io.kotest.matchers.equals.shouldBeEqual
+import org.junit.jupiter.api.Test
+
+class StringUtilsKtTest {
+    @Test
+    fun `when string is less than max character limit, then return same string`() {
+        val input = "testyy"
+        input.cutOff(100).shouldBeEqual(input)
+    }
+
+    @Test
+    fun `when string is longer than max character limit, then return truncated string with ellipsis`() {
+        val input = "Testyyyyyyyyyyyyyyyyyyyy"
+        input.cutOff(5).shouldBeEqual("Test…")
+    }
+
+    @Test
+    fun `when max character limit is negative, then throw exception`() {
+        val exception =
+            shouldThrow<IllegalArgumentException> {
+                "willCrash".cutOff(-10)
+            }
+        exception.message?.shouldBeEqual("Character limit should be at least 1")
+    }
+
+    @Test
+    fun `when max character limit is 0, then throw exception`() {
+        val exception =
+            shouldThrow<IllegalArgumentException> {
+                "willCrash".cutOff(0)
+            }
+        exception.message?.shouldBeEqual("Character limit should be at least 1")
+    }
+
+    @Test
+    fun `when max character limit is 1, then return ellipsis character`() {
+        "testy".cutOff(1).shouldBeEqual("…")
+    }
+}