AK+Everywhere: Consolidate String::index_of() and String::find()

We had two functions for doing mostly the same thing. Combine both
of them into String::find() and use that everywhere.

Also add some tests to cover basic behavior.

1 files changed, 16 insertions, 0 deletions

diff --git a/Tests/AK/TestString.cpp b/Tests/AK/TestString.cpp
index 40953ec418..01c6368c58 100644
--- a/Tests/AK/TestString.cpp
+++ b/Tests/AK/TestString.cpp
@@ -255,3 +255,19 @@ TEST_CASE(sprintf)
     EXPECT_EQ(String(buf1), String("+12"));
     EXPECT_EQ(String(buf2), String("-12"));
 }
+
+TEST_CASE(find)
+{
+    String a = "foobarbar";
+    EXPECT_EQ(a.find("bar"sv), Optional<size_t> { 3 });
+    EXPECT_EQ(a.find("baz"sv), Optional<size_t> {});
+    EXPECT_EQ(a.find("bar"sv, 4), Optional<size_t> { 6 });
+    EXPECT_EQ(a.find("bar"sv, 9), Optional<size_t> {});
+
+    EXPECT_EQ(a.find('f'), Optional<size_t> { 0 });
+    EXPECT_EQ(a.find('x'), Optional<size_t> {});
+    EXPECT_EQ(a.find('f', 1), Optional<size_t> {});
+    EXPECT_EQ(a.find('b'), Optional<size_t> { 3 });
+    EXPECT_EQ(a.find('b', 4), Optional<size_t> { 6 });
+    EXPECT_EQ(a.find('b', 9), Optional<size_t> {});
+}