From 24bc674d94c56d9fc6ac06f442bcf23d8f2db14f Mon Sep 17 00:00:00 2001
From: Shannon Booth <shannon.ml.booth@gmail.com>
Date: Mon, 30 Dec 2019 01:44:30 +1300
Subject: [PATCH] AK: Add StringView::ends_with function

---
 AK/StringView.cpp           | 11 +++++++++++
 AK/StringView.h             |  1 +
 AK/Tests/TestStringView.cpp | 10 ++++++++++
 3 files changed, 22 insertions(+)

diff --git a/AK/StringView.cpp b/AK/StringView.cpp
index 12f39049e1e..54c1e21dcc4 100644
--- a/AK/StringView.cpp
+++ b/AK/StringView.cpp
@@ -92,6 +92,17 @@ bool StringView::starts_with(const StringView& str) const
     return !memcmp(characters_without_null_termination(), str.characters_without_null_termination(), str.length());
 }
 
+bool StringView::ends_with(const StringView& str) const
+{
+    if (str.is_empty())
+        return true;
+    if (is_empty())
+        return false;
+    if (str.length() > length())
+        return false;
+    return !memcmp(characters_without_null_termination() + length() - str.length(), str.characters_without_null_termination(), str.length());
+}
+
 StringView StringView::substring_view(size_t start, size_t length) const
 {
     if (!length)
diff --git a/AK/StringView.h b/AK/StringView.h
index e8cdbbbd450..d26d64c4d56 100644
--- a/AK/StringView.h
+++ b/AK/StringView.h
@@ -42,6 +42,7 @@ public:
     unsigned hash() const;
 
     bool starts_with(const StringView&) const;
+    bool ends_with(const StringView&) const;
 
     StringView substring_view(size_t start, size_t length) const;
     Vector<StringView> split_view(char, bool keep_empty = false) const;
diff --git a/AK/Tests/TestStringView.cpp b/AK/Tests/TestStringView.cpp
index efe25961514..e1af2efa467 100644
--- a/AK/Tests/TestStringView.cpp
+++ b/AK/Tests/TestStringView.cpp
@@ -42,6 +42,16 @@ TEST_CASE(starts_with)
     EXPECT(!test_string_view.starts_with("DEF"));
 }
 
+TEST_CASE(ends_with)
+{
+    String test_string = "ABCDEF";
+    StringView test_string_view = test_string.view();
+    EXPECT(test_string_view.ends_with("DEF"));
+    EXPECT(test_string_view.ends_with("ABCDEF"));
+    EXPECT(!test_string_view.ends_with("ABCDE"));
+    EXPECT(!test_string_view.ends_with("ABCDEFG"));
+}
+
 TEST_CASE(lines)
 {
     String test_string = "a\nb\r\nc\rd";