From 70b606166640d043fc7b78a52b89ff1bba798b6a Mon Sep 17 00:00:00 2001
From: Ashkan Kiani <ashkan.k.kiani@gmail.com>
Date: Sun, 1 Dec 2019 05:32:55 -0800
Subject: Add vim.startswith and vim.endswith (#11248)

---
 runtime/lua/vim/shared.lua | 20 ++++++++++++++++++++
 1 file changed, 20 insertions(+)

(limited to 'runtime/lua/vim')

diff --git a/runtime/lua/vim/shared.lua b/runtime/lua/vim/shared.lua
index 631dd04c35..b5b04d7757 100644
--- a/runtime/lua/vim/shared.lua
+++ b/runtime/lua/vim/shared.lua
@@ -320,6 +320,26 @@ function vim.pesc(s)
   return s:gsub('[%(%)%.%%%+%-%*%?%[%]%^%$]', '%%%1')
 end
 
+--- Test if `prefix` is a prefix of `s` for strings.
+--
+-- @param s String to check
+-- @param prefix Potential prefix
+-- @return boolean True if prefix is a prefix of s
+function vim.startswith(s, prefix)
+  vim.validate { s = {s, 's'}; prefix = {prefix, 's'}; }
+  return s:sub(1, #prefix) == prefix
+end
+
+--- Test if `suffix` is a suffix of `s` for strings.
+--
+-- @param s String to check
+-- @param suffix Potential suffix
+-- @return boolean True if suffix is a suffix of s
+function vim.endswith(s, suffix)
+  vim.validate { s = {s, 's'}; suffix = {suffix, 's'}; }
+  return #suffix == 0 or s:sub(-#suffix) == suffix
+end
+
 --- Validates a parameter specification (types and values).
 ---
 --- Usage example:
-- 
cgit