From 018d54d65a3fe8249d913c06f53297bfb9f80bf7 Mon Sep 17 00:00:00 2001
From: Jaden Fix <jadenfix20@gmail.com>
Date: Sun, 18 Oct 2026 04:15:57 -0700
Subject: [PATCH] Expose static descriptions for parser errors

Make the existing Error::description_str accessor public so callers can obtain the display message without allocating or relying on the deprecated std::error::Error::description method. Cover every variant through the public API and exercise a description surviving a parsed error.
---
 src/lib.rs                 | 11 ++++++++++-
 tests/error_description.rs | 29 +++++++++++++++++++++++++++++
 2 files changed, 39 insertions(+), 1 deletion(-)
 create mode 100644 tests/error_description.rs

diff --git a/src/lib.rs b/src/lib.rs
index 98b37c7..6041423 100644
--- a/src/lib.rs
+++ b/src/lib.rs
@@ -117,8 +117,17 @@ pub enum Error {
 }
 
 impl Error {
+    /// Returns the error's description as a static string.
+    ///
+    /// This is the same message produced by the [`Display`](fmt::Display)
+    /// implementation, without allocating a string.
+    ///
+    /// ```
+    /// let description: &'static str = httparse::Error::HeaderName.description_str();
+    /// assert_eq!(description, "invalid header name");
+    /// ```
     #[inline]
-    fn description_str(&self) -> &'static str {
+    pub fn description_str(&self) -> &'static str {
         match *self {
             Error::HeaderName => "invalid header name",
             Error::HeaderValue => "invalid header value",
diff --git a/tests/error_description.rs b/tests/error_description.rs
new file mode 100644
index 0000000..8af270f
--- /dev/null
+++ b/tests/error_description.rs
@@ -0,0 +1,29 @@
+use httparse::{Error, Request, EMPTY_HEADER};
+
+#[test]
+fn error_descriptions_are_static_and_match_display() {
+    for error in [
+        Error::HeaderName,
+        Error::HeaderValue,
+        Error::NewLine,
+        Error::Status,
+        Error::Token,
+        Error::TooManyHeaders,
+        Error::Version,
+    ] {
+        let description: &'static str = error.description_str();
+        assert_eq!(description, error.to_string());
+    }
+}
+
+#[test]
+fn parsed_error_description_outlives_the_error() {
+    let description: &'static str = {
+        let mut headers = [EMPTY_HEADER; 1];
+        let error = Request::new(&mut headers)
+            .parse(b"GET / HTTP/1.1\r\ninvalid header: value\r\n\r\n")
+            .unwrap_err();
+        error.description_str()
+    };
+    assert_eq!(description, "invalid header name");
+}