Move fragment preservation test to directly test our redirect handling logic (#14480)

When [updating](https://github.com/astral-sh/uv/pull/14475) to the
latest `reqwest` version, our fragment propagation test broke. That test
was partially testing the `reqwest` behavior, so this PR moves the
fragment test to directly test our logic for constructing redirect
requests.

crates/uv-client/src/base_client.rs

@@ -982,6 +982,45 @@ mod tests {
         Ok(())
     }
 
+    #[tokio::test]
+    async fn test_redirect_preserves_fragment() -> Result<()> {
+        for status in &[301, 302, 303, 307, 308] {
+            let server = MockServer::start().await;
+            Mock::given(method("GET"))
+                .respond_with(
+                    ResponseTemplate::new(*status)
+                        .insert_header("location", format!("{}/redirect", server.uri())),
+                )
+                .mount(&server)
+                .await;
+
+            let request = Client::new()
+                .get(format!("{}#fragment", server.uri()))
+                .build()
+                .unwrap();
+
+            let response = Client::builder()
+                .redirect(reqwest::redirect::Policy::none())
+                .build()
+                .unwrap()
+                .execute(request.try_clone().unwrap())
+                .await
+                .unwrap();
+
+            let redirect_request =
+                request_into_redirect(request, &response, CrossOriginCredentialsPolicy::Secure)?
+                    .unwrap();
+            assert!(
+                redirect_request
+                    .url()
+                    .fragment()
+                    .is_some_and(|fragment| fragment == "fragment")
+            );
+        }
+
+        Ok(())
+    }
+
     #[tokio::test]
     async fn test_redirect_removes_authorization_header_on_cross_origin() -> Result<()> {
         for status in &[301, 302, 303, 307, 308] {

crates/uv-client/src/registry_client.rs

@@ -1416,44 +1416,6 @@ mod tests {
         Ok(())
     }
 
-    #[tokio::test]
-    async fn test_redirect_preserve_fragment() -> Result<(), Error> {
-        let redirect_server = MockServer::start().await;
-
-        // Configure the redirect server to respond with a 307 with a relative URL.
-        Mock::given(method("GET"))
-            .respond_with(ResponseTemplate::new(307).insert_header("Location", "/foo".to_string()))
-            .mount(&redirect_server)
-            .await;
-
-        Mock::given(method("GET"))
-            .and(path_regex("/foo"))
-            .respond_with(ResponseTemplate::new(200))
-            .mount(&redirect_server)
-            .await;
-
-        let cache = Cache::temp()?;
-        let registry_client = RegistryClientBuilder::new(cache).build();
-        let client = registry_client.cached_client().uncached();
-
-        let mut url = DisplaySafeUrl::parse(&redirect_server.uri())?;
-        url.set_fragment(Some("fragment"));
-
-        assert_eq!(
-            client
-                .for_host(&url)
-                .get(Url::from(url.clone()))
-                .send()
-                .await?
-                .url()
-                .to_string(),
-            format!("{}/foo#fragment", redirect_server.uri()),
-            "Requests should preserve fragment"
-        );
-
-        Ok(())
-    }
-
     #[test]
     fn ignore_failing_files() {
         // 1.7.7 has an invalid requires-python field (double comma), 1.7.8 is valid