Display ssh git username in Debug implementation (#13806)

This updates the `Debug` implementation of `DisplaySafeUrl` to display
the git username in a case like `git+ssh://git@github.com/org/repo`. It
also factors out the git username check into a shared function and adds
related unit tests to `DisplaySafeUrl`.

crates/uv-redacted/src/lib.rs

@@ -91,10 +91,7 @@ impl DisplaySafeUrl {
     pub fn remove_credentials(&mut self) {
         // For URLs that use the `git` convention (i.e., `ssh://git@github.com/...`), avoid dropping the
         // username.
-        if matches!(self.0.scheme(), "git+ssh" | "ssh")
+        if is_ssh_git_username(&self.0) {
-            && self.0.username() == "git"
-            && self.0.password().is_none()
-        {
             return;
         }
         let _ = self.0.set_username("");
@@ -131,7 +128,11 @@ impl Display for DisplaySafeUrl {
 impl Debug for DisplaySafeUrl {
     fn fmt(&self, f: &mut std::fmt::Formatter<'_>) -> std::fmt::Result {
         let url = &self.0;
-        let (username, password) = if url.username() != "" && url.password().is_some() {
+        // For URLs that use the `git` convention (i.e., `ssh://git@github.com/...`), avoid masking the
+        // username.
+        let (username, password) = if is_ssh_git_username(url) {
+            (url.username(), None)
+        } else if url.username() != "" && url.password().is_some() {
             (url.username(), Some("****"))
         } else if url.username() != "" {
             ("****", None)
@@ -175,6 +176,10 @@ impl FromStr for DisplaySafeUrl {
     }
 }
 
+fn is_ssh_git_username(url: &Url) -> bool {
+    matches!(url.scheme(), "ssh" | "git+ssh") && url.username() == "git" && url.password().is_none()
+}
+
 fn display_with_redacted_credentials(
     url: &Url,
     f: &mut std::fmt::Formatter<'_>,
@@ -185,10 +190,7 @@ fn display_with_redacted_credentials(
 
     // For URLs that use the `git` convention (i.e., `ssh://git@github.com/...`), avoid dropping the
     // username.
-    if matches!(url.scheme(), "git+ssh" | "ssh")
+    if is_ssh_git_username(url) {
-        && url.username() == "git"
-        && url.password().is_none()
-    {
         return write!(f, "{url}");
     }
 
@@ -231,7 +233,7 @@ mod tests {
         let log_safe_url = DisplaySafeUrl::from(url);
         assert_eq!(log_safe_url.username(), "");
         assert!(log_safe_url.password().is_none());
-        assert_eq!(format!("{log_safe_url}"), url_str);
+        assert_eq!(log_safe_url.to_string(), url_str);
     }
 
     #[test]
@@ -242,7 +244,7 @@ mod tests {
         assert_eq!(log_safe_url.username(), "user");
         assert!(log_safe_url.password().is_some_and(|p| p == "pass"));
         assert_eq!(
-            format!("{log_safe_url}"),
+            log_safe_url.to_string(),
             "https://user:****@pypi-proxy.fly.dev/basic-auth/simple"
         );
     }
@@ -255,7 +257,7 @@ mod tests {
         assert_eq!(log_safe_url.username(), "");
         assert!(log_safe_url.password().is_some_and(|p| p == "pass"));
         assert_eq!(
-            format!("{log_safe_url}"),
+            log_safe_url.to_string(),
             "https://:****@pypi-proxy.fly.dev/basic-auth/simple"
         );
     }
@@ -268,11 +270,26 @@ mod tests {
         assert_eq!(log_safe_url.username(), "user");
         assert!(log_safe_url.password().is_none());
         assert_eq!(
-            format!("{log_safe_url}"),
+            log_safe_url.to_string(),
             "https://****@pypi-proxy.fly.dev/basic-auth/simple"
         );
     }
 
+    #[test]
+    fn from_url_git_username() {
+        let ssh_str = "ssh://git@github.com/org/repo";
+        let ssh_url = DisplaySafeUrl::parse(ssh_str).unwrap();
+        assert_eq!(ssh_url.username(), "git");
+        assert!(ssh_url.password().is_none());
+        assert_eq!(ssh_url.to_string(), ssh_str);
+        // Test again for the `git+ssh` scheme
+        let git_ssh_str = "git+ssh://git@github.com/org/repo";
+        let git_ssh_url = DisplaySafeUrl::parse(git_ssh_str).unwrap();
+        assert_eq!(git_ssh_url.username(), "git");
+        assert!(git_ssh_url.password().is_none());
+        assert_eq!(git_ssh_url.to_string(), git_ssh_str);
+    }
+
     #[test]
     fn parse_url_string() {
         let url_str = "https://user:pass@pypi-proxy.fly.dev/basic-auth/simple";
@@ -280,7 +297,7 @@ mod tests {
         assert_eq!(log_safe_url.username(), "user");
         assert!(log_safe_url.password().is_some_and(|p| p == "pass"));
         assert_eq!(
-            format!("{log_safe_url}"),
+            log_safe_url.to_string(),
             "https://user:****@pypi-proxy.fly.dev/basic-auth/simple"
         );
     }
@@ -293,17 +310,34 @@ mod tests {
         assert_eq!(log_safe_url.username(), "");
         assert!(log_safe_url.password().is_none());
         assert_eq!(
-            format!("{log_safe_url}"),
+            log_safe_url.to_string(),
             "https://pypi-proxy.fly.dev/basic-auth/simple"
         );
     }
 
+    #[test]
+    fn preserve_ssh_git_username_on_remove_credentials() {
+        let ssh_str = "ssh://git@pypi-proxy.fly.dev/basic-auth/simple";
+        let mut ssh_url = DisplaySafeUrl::parse(ssh_str).unwrap();
+        ssh_url.remove_credentials();
+        assert_eq!(ssh_url.username(), "git");
+        assert!(ssh_url.password().is_none());
+        assert_eq!(ssh_url.to_string(), ssh_str);
+        // Test again for `git+ssh` scheme
+        let git_ssh_str = "git+ssh://git@pypi-proxy.fly.dev/basic-auth/simple";
+        let mut git_shh_url = DisplaySafeUrl::parse(git_ssh_str).unwrap();
+        git_shh_url.remove_credentials();
+        assert_eq!(git_shh_url.username(), "git");
+        assert!(git_shh_url.password().is_none());
+        assert_eq!(git_shh_url.to_string(), git_ssh_str);
+    }
+
     #[test]
     fn displayable_with_credentials() {
         let url_str = "https://user:pass@pypi-proxy.fly.dev/basic-auth/simple";
         let log_safe_url = DisplaySafeUrl::parse(url_str).unwrap();
         assert_eq!(
-            &log_safe_url.displayable_with_credentials().to_string(),
+            log_safe_url.displayable_with_credentials().to_string(),
             url_str
         );
     }
@@ -313,7 +347,7 @@ mod tests {
         let url_str = "https://token@example.com/abc/";
         let log_safe_url = DisplaySafeUrl::parse(url_str).unwrap();
         let foo_url = log_safe_url.join("foo").unwrap();
-        assert_eq!(format!("{foo_url}"), "https://****@example.com/abc/foo");
+        assert_eq!(foo_url.to_string(), "https://****@example.com/abc/foo");
     }
 
     #[test]
@@ -324,7 +358,7 @@ mod tests {
         assert_eq!(log_safe_url.username(), "user");
         assert!(log_safe_url.password().is_some_and(|p| p == "pass"));
         assert_eq!(
-            format!("{log_safe_url}"),
+            log_safe_url.to_string(),
             "https://user:****@pypi-proxy.fly.dev/basic-auth/simple"
         );
     }