update

lib/md_colors.lua

@@ -293,3 +293,5 @@ md_colors = {
     blue_grey_800="#37474F",
     blue_grey_900="#263238",
 }
+
+return md_colors

lib/url.lua

@@ -0,0 +1,51 @@
+--- Python-style URL quoting library.
+--
+-- @module pl.url
+
+local url = {}
+
+local function quote_char(c)
+    return string.format("%%%02X", string.byte(c))
+end
+
+--- Quote the url, replacing special characters using the '%xx' escape.
+-- @string s the string
+-- @bool quote_plus Also escape slashes and replace spaces by plus signs.
+-- @return The quoted string, or if `s` wasn't a string, just plain unaltered `s`.
+function url.quote(s, quote_plus)
+    if type(s) ~= "string" then
+        return s
+    end
+
+    s = s:gsub("\n", "\r\n")
+    s = s:gsub("([^A-Za-z0-9 %-_%./])", quote_char)
+    if quote_plus then
+        s = s:gsub(" ", "+")
+        s = s:gsub("/", quote_char)
+    else
+        s = s:gsub(" ", "%%20")
+    end
+
+    return s
+end
+
+local function unquote_char(h)
+    return string.char(tonumber(h, 16))
+end
+
+--- Unquote the url, replacing '%xx' escapes and plus signs.
+-- @string s the string
+-- @return The unquoted string, or if `s` wasn't a string, just plain unaltered `s`.
+function url.unquote(s)
+    if type(s) ~= "string" then
+        return s
+    end
+
+    s = s:gsub("+", " ")
+    s = s:gsub("%%(%x%x)", unquote_char)
+    s = s:gsub("\r\n", "\n")
+
+    return s
+end
+
+return url