From e51116c2b229e9031125161569f177e21703747a Mon Sep 17 00:00:00 2001
From: Gareth Pendleton <gareth.sidebottom@gmail.com>
Date: Mon, 27 Oct 2025 19:08:18 +0000
Subject: [PATCH] fix: Fix uri encoding/decoding and add new tests

---
 src/gluri/internal/utils.gleam | 14 +++--------
 test/gluri_test.gleam          | 46 +++++++++++++++-------------------
 2 files changed, 23 insertions(+), 37 deletions(-)

diff --git a/src/gluri/internal/utils.gleam b/src/gluri/internal/utils.gleam
index 4e54d8e..1612549 100644
--- a/src/gluri/internal/utils.gleam
+++ b/src/gluri/internal/utils.gleam
@@ -109,7 +109,7 @@ pub fn parse_min_max(
   do_parse_min_max(str, "", min, max, parse_fn)
 }
 
-pub fn do_parse_min_max(
+fn do_parse_min_max(
   str: d,
   acc: String,
   min: Int,
@@ -403,14 +403,6 @@ pub fn parse_hex_digits(str, min, max) {
   parse_min_max(str, min, max, parse_hex_digit)
 }
 
-fn encoding_not_needed(i: Int) -> Bool {
-  // $-_.+!*'()
-  case i {
-    36 | 45 | 95 | 46 | 43 | 33 | 42 | 39 | 40 | 41 -> True
-    _ -> False
-  }
-}
-
 fn is_unreserved_char(i: Int) -> Bool {
   case i {
     45 | 46 | 95 | 126 -> True
@@ -660,13 +652,13 @@ pub fn do_percent_encode(str: String) -> String {
 fn encode_codepoint(codepoint: Int) -> String {
   case codepoint <= 127 {
     True -> {
-      case is_unreserved_char(codepoint) || encoding_not_needed(codepoint) {
+      case is_unreserved_char(codepoint) {
         True -> {
           let assert Ok(cpnt) = string.utf_codepoint(codepoint)
           string.from_utf_codepoints([cpnt])
         }
         False -> {
-          "%" <> int.to_base16(codepoint)
+          "%" <> string.pad_start(int.to_base16(codepoint), 2, "0")
         }
       }
     }
diff --git a/test/gluri_test.gleam b/test/gluri_test.gleam
index 3a2ad49..2157e2e 100644
--- a/test/gluri_test.gleam
+++ b/test/gluri_test.gleam
@@ -1146,37 +1146,31 @@ pub fn equivalence_tests() {
   ])
 }
 
-const percent_codec_fixtures = [
-  #(" ", "%20"),
-  #(",", "%2C"),
-  #(";", "%3B"),
-  #(":", "%3A"),
-  #("!", "!"),
-  #("?", "%3F"),
-  #("'", "'"),
-  #("(", "("),
-  #(")", ")"),
-  #("[", "%5B"),
-  #("@", "%40"),
-  #("/", "%2F"),
-  #("\\", "%5C"),
+const percent_encode_examples = [
+  #("", ""),
+  #("%", "%25"),
+  #("%%", "%25%25"),
+  #(" \r\n\t\u{B}\f", "%20%0D%0A%09%0B%0C"),
+  #(
+    "-_.~0123456789abcdefghijklmnopqrstuvwxyzABCDEFGHIJKLMNOPQRSTUVWXYZ",
+    "-_.~0123456789abcdefghijklmnopqrstuvwxyzABCDEFGHIJKLMNOPQRSTUVWXYZ",
+  ),
+  #("\u{0}", "%00"),
+  #("abc\u{00}def", "abc%00def"),
   #("&", "%26"),
-  #("#", "%23"),
-  #("=", "%3D"),
-  #("~", "~"),
-  #("ñ", "%C3%B1"),
-  #("-", "-"),
-  #("_", "_"),
-  #(".", "."),
-  #("*", "*"),
-  #("+", "+"),
-  #("100% great+fun", "100%25%20great+fun"),
+  #(
+    "!\"#$%&'()*+,-./:;<=>?@[\\]^_`{|}~",
+    "%21%22%23%24%25%26%27%28%29%2A%2B%2C-.%2F%3A%3B%3C%3D%3E%3F%40%5B%5C%5D%5E_%60%7B%7C%7D~",
+  ),
+  #("“Aha”", "%E2%80%9CAha%E2%80%9D"),
+  #("\u{201C}Aha\u{201D}", "%E2%80%9CAha%E2%80%9D"),
+  #("*+,=>/", "%2A%2B%2C%3D%3E%2F"),
 ]
 
 pub fn percent_encode_tests() {
   describe("percent encoding", [
     it("encoding", fn() {
-      percent_codec_fixtures
+      percent_encode_examples
       |> list.map(fn(t) {
         let #(a, b) = t
         uri.percent_encode(a)
@@ -1185,7 +1179,7 @@ pub fn percent_encode_tests() {
       Nil
     }),
     it("decoding", fn() {
-      percent_codec_fixtures
+      percent_encode_examples
       |> list.map(fn(t) {
         let #(a, b) = t
         uri.percent_decode(b)