From 38ce857870de7ee99f1b9a1e730dc7cdd8662909 Mon Sep 17 00:00:00 2001
From: =?UTF-8?q?Christian=20Kohlschu=CC=88tter?=
 <christian@kohlschutter.com>
Date: Sun, 31 Dec 2023 13:47:17 +0100
Subject: [PATCH] common: Add #contains

---
 .../com/kohlschutter/stringhold/StringHolder.java  | 14 ++++++++++++--
 .../kohlschutter/stringhold/StringHolderTest.java  |  6 ++++++
 2 files changed, 18 insertions(+), 2 deletions(-)

diff --git a/stringhold-common/src/main/java/com/kohlschutter/stringhold/StringHolder.java b/stringhold-common/src/main/java/com/kohlschutter/stringhold/StringHolder.java
index 6cd9b18..587f39e 100644
--- a/stringhold-common/src/main/java/com/kohlschutter/stringhold/StringHolder.java
+++ b/stringhold-common/src/main/java/com/kohlschutter/stringhold/StringHolder.java
@@ -742,8 +742,18 @@ default int indexOf(int c) {
   }
 
   /**
-   * Returns the index within this StringHolder of the first occurrence of the specified
-   * CharSequence, or {@code -1} if not found.
+   * Checks if this {@link StringHolder} contains the given {@link CharSequence}.
+   * 
+   * @param s The char sequence to look for.
+   * @return {@code true} if found (also if the sequence is empty).
+   */
+  default boolean contains(CharSequence s) {
+    return indexOf(s.toString()) >= 0;
+  }
+
+  /**
+   * Returns the index within this {@link StringHolder} of the first occurrence of the specified
+   * {@link CharSequence}, or {@code -1} if not found.
    *
    * @param str The char sequence to look for.
    * @return The position, or {@code -1} if not found.
diff --git a/stringhold-common/src/test/java/com/kohlschutter/stringhold/StringHolderTest.java b/stringhold-common/src/test/java/com/kohlschutter/stringhold/StringHolderTest.java
index 1e5c8ba..dab9eb8 100644
--- a/stringhold-common/src/test/java/com/kohlschutter/stringhold/StringHolderTest.java
+++ b/stringhold-common/src/test/java/com/kohlschutter/stringhold/StringHolderTest.java
@@ -1423,4 +1423,10 @@ public void testIndexOfSelf() throws Exception {
     sh = StringHolder.withSupplier(() -> "");
     assertEquals(0, sh.indexOf(sh));
   }
+
+  @Test
+  public void testContains() throws Exception {
+    assertTrue(StringHolder.withContent("Foo bar").contains("bar"));
+    assertFalse(StringHolder.withContent("Foo bar").contains("baz"));
+  }
 }