From 8b8d3e577ec06df76ec8b2e3635f17e42c1e40a7 Mon Sep 17 00:00:00 2001
From: Gareth Pendleton <gareth.sidebottom@gmail.com>
Date: Sun, 14 Sep 2025 17:11:04 +0100
Subject: [PATCH] perf: Add tweak to parse known schema more quickly

http, https, and a few other urls can be assumed to be possible schemes.
If we check for these then we cut down on the character by character
parsing that would otherwise happen
---
 src/gluri/internal/parser.gleam | 30 +++++++++++++++++++++++-------
 1 file changed, 23 insertions(+), 7 deletions(-)

diff --git a/src/gluri/internal/parser.gleam b/src/gluri/internal/parser.gleam
index 7c9406d..783630c 100644
--- a/src/gluri/internal/parser.gleam
+++ b/src/gluri/internal/parser.gleam
@@ -603,15 +603,31 @@ fn parse_userinfo(
 }
 
 fn parse_scheme(str: String) -> Result(#(Uri, String), Nil) {
-  case parse_alpha(str) {
-    Ok(#(first, rest)) -> {
-      case do_parse_scheme(rest, first) {
-        Error(_) -> Error(Nil)
-        Ok(#(scheme, rest)) ->
-          Ok(#(Uri(Some(scheme), None, None, None, "", None, None), rest))
+  case str {
+    "http:" <> rest ->
+      Ok(#(Uri(Some("http"), None, None, None, "", None, None), rest))
+    "https:" <> rest ->
+      Ok(#(Uri(Some("https"), None, None, None, "", None, None), rest))
+    "ftp:" <> rest ->
+      Ok(#(Uri(Some("ftp"), None, None, None, "", None, None), rest))
+    "file:" <> rest ->
+      Ok(#(Uri(Some("file"), None, None, None, "", None, None), rest))
+    "ws:" <> rest ->
+      Ok(#(Uri(Some("ws"), None, None, None, "", None, None), rest))
+    "wss:" <> rest ->
+      Ok(#(Uri(Some("wss"), None, None, None, "", None, None), rest))
+    _ -> {
+      case parse_alpha(str) {
+        Ok(#(first, rest)) -> {
+          case do_parse_scheme(rest, first) {
+            Error(_) -> Error(Nil)
+            Ok(#(scheme, rest)) ->
+              Ok(#(Uri(Some(scheme), None, None, None, "", None, None), rest))
+          }
+        }
+        _ -> Error(Nil)
       }
     }
-    _ -> Error(Nil)
   }
 }