AK: Add String starts_with(char) & ends_with(char)

This is simply meant to be a more efficient implementation in the
case that we only need to check a single character.
This commit is contained in:
Shannon Booth 2020-02-15 13:04:00 +13:00 committed by Andreas Kling
parent 0e3a9d8e9d
commit 9920d17342
3 changed files with 19 additions and 0 deletions

View file

@ -295,6 +295,13 @@ bool String::starts_with(const StringView& str) const
return !memcmp(characters(), str.characters_without_null_termination(), str.length());
}
bool String::starts_with(char ch) const
{
if (is_empty())
return false;
return characters()[0] == ch;
}
bool String::ends_with(const StringView& str) const
{
if (str.is_empty())
@ -306,6 +313,12 @@ bool String::ends_with(const StringView& str) const
return !memcmp(characters() + (length() - str.length()), str.characters_without_null_termination(), str.length());
}
bool String::ends_with(char ch) const
{
if (is_empty())
return false;
return characters()[length() - 1] == ch;
}
String String::repeated(char ch, size_t count)
{
if (!count)

View file

@ -157,6 +157,8 @@ public:
bool starts_with(const StringView&) const;
bool ends_with(const StringView&) const;
bool starts_with(char) const;
bool ends_with(char) const;
bool operator==(const String&) const;
bool operator!=(const String& other) const { return !(*this == other); }

View file

@ -80,6 +80,8 @@ TEST_CASE(starts_with)
{
String test_string = "ABCDEF";
EXPECT(test_string.starts_with("AB"));
EXPECT(test_string.starts_with('A'));
EXPECT(!test_string.starts_with('B'));
EXPECT(test_string.starts_with("ABCDEF"));
EXPECT(!test_string.starts_with("DEF"));
}
@ -88,6 +90,8 @@ TEST_CASE(ends_with)
{
String test_string = "ABCDEF";
EXPECT(test_string.ends_with("EF"));
EXPECT(test_string.ends_with('F'));
EXPECT(!test_string.ends_with('E'));
EXPECT(test_string.ends_with("ABCDEF"));
EXPECT(!test_string.ends_with("ABC"));
}