Merge pull request #269 from henricook/string-contains

Support case insensitive string contains
typelevel · May 11, 2023 · bfb7f1f · bfb7f1f
2 parents 899559d + c4a0a8f
commit bfb7f1f
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Showing 3 changed files with 42 additions and 1 deletion.
diff --git a/core/src/main/scala/org/typelevel/ci/CIString.scala b/core/src/main/scala/org/typelevel/ci/CIString.scala
@@ -98,6 +98,17 @@ final class CIString private (override val toString: String)
 
   def length: Int = toString.length
 
+  def contains(needle: CIString): Boolean = {
+    val needleLength = needle.toString.length
+    val haystack = toString
+    // There's no point searching haystack indexes beyond which the substring is too small to ever match the needle
+    val maxHaystackStartingIndex = haystack.length - needleLength
+
+    (0 to maxHaystackStartingIndex).exists { i =>
+      haystack.regionMatches(true, i, needle.toString, 0, needleLength)
+    }
+  }
+
   @deprecated("Use toString", "0.1.0")
   def value: String = toString
 }

diff --git a/tests/shared/src/test/scala/org/typelevel/ci/CIStringSuite.scala b/tests/shared/src/test/scala/org/typelevel/ci/CIStringSuite.scala
@@ -183,6 +183,31 @@ class CIStringSuite extends DisciplineSuite {
     })
   }
 
+  test("contains lowercase to lowercase is true if matching") {
+    assert(CIString("hello there").contains(CIString("hello there")))
+    assert(CIString("hello there").contains(CIString("hello")))
+  }
+
+  test("contains lowercase to lowercase is false if not matching") {
+    assertEquals(CIString("hello there").contains(CIString("guten arben")), false)
+  }
+
+  test("contains lowercase to mixed case is false if not matching") {
+    assertEquals(CIString("hello there").contains(CIString("GUTEN ARBEN")), false)
+  }
+
+  test("contains mixed to mixed case is true if matching") {
+    assert(CIString("HELLO there").contains(CIString("hellO ThErE")))
+  }
+
+  test("contains uppercase to mixed case is true if matching") {
+    assert(CIString("HELLO THERE").contains(CIString("hellO ThErE")))
+  }
+
+  test("contains uppercase to mixed case is false if not matching") {
+    assertEquals(CIString("HELLO THERE").contains(CIString("GUTEN arben")), false)
+  }
+
   checkAll("Order[CIString]", OrderTests[CIString].order)
   checkAll("Hash[CIString]", HashTests[CIString].hash)
   checkAll("LowerBounded[CIString]", LowerBoundedTests[CIString].lowerBounded)

diff --git a/tests/shared/src/test/scala/org/typelevel/ci/TurkeySuite.scala b/tests/shared/src/test/scala/org/typelevel/ci/TurkeySuite.scala
@@ -19,7 +19,12 @@ package org.typelevel.ci
 import munit.FunSuite
 
 class TurkeySuite extends FunSuite {
-  test("passes the Turkey test") {
+  test("equals passes the Turkey test") {
     assertEquals(CIString("i"), CIString("I"))
   }
+
+  test("contains passes the Turkey test") {
+    assert(CIString("i").contains(CIString("I")))
+    assert(CIString("I").contains(CIString("i")))
+  }
 }