feat(progress): Allow querying support

Author: epage

crates/anstyle-progress/src/lib.rs

@@ -12,9 +12,11 @@
 #![warn(clippy::print_stdout)]
 
 mod progress;
+mod query;
 
 pub use progress::TermProgress;
 pub use progress::TermProgressStatus;
+pub use query::supports_term_progress;
 
 #[doc = include_str!("../README.md")]
 #[cfg(doctest)]

crates/anstyle-progress/src/query.rs

@@ -0,0 +1,59 @@
+/// Determines whether the terminal supports ANSI OSC 9;4.
+pub fn supports_term_progress(is_terminal: bool) -> bool {
+    let windows_terminal = std::env::var("WT_SESSION").is_ok();
+    let conemu = std::env::var("ConEmuANSI").ok() == Some("ON".into());
+    let wezterm = std::env::var("TERM_PROGRAM").ok() == Some("WezTerm".into());
+    let ghostty = std::env::var("TERM_PROGRAM").ok() == Some("ghostty".into());
+    // iTerm added OSC 9;4 support in v3.6.6, which we can check for.
+    // For context: https://github.com/rust-lang/cargo/pull/16506#discussion_r2706584034
+    let iterm = std::env::var("TERM_PROGRAM").ok() == Some("iTerm.app".into())
+        && std::env::var("TERM_FEATURES")
+            .ok()
+            .map(|v| term_features_has_progress(&v))
+            .unwrap_or(false);
+    // Ptyxis added OSC 9;4 support in 48.0.
+    // See https://gitlab.gnome.org/chergert/ptyxis/-/issues/305
+    let ptyxis = std::env::var("PTYXIS_VERSION")
+        .ok()
+        .and_then(|version| version.split(".").next()?.parse::<i32>().ok())
+        .map(|major_version| major_version >= 48)
+        .unwrap_or(false);
+
+    (windows_terminal || conemu || wezterm || ghostty || iterm || ptyxis) && is_terminal
+}
+
+// For iTerm, the TERM_FEATURES value "P" indicates OSC 9;4 support.
+// Context: https://iterm2.com/feature-reporting/
+fn term_features_has_progress(value: &str) -> bool {
+    let mut current = String::new();
+
+    for ch in value.chars() {
+        if !ch.is_ascii_alphanumeric() {
+            break;
+        }
+        if ch.is_ascii_uppercase() {
+            if current == "P" {
+                return true;
+            }
+            current.clear();
+            current.push(ch);
+        } else {
+            current.push(ch);
+        }
+    }
+    current == "P"
+}
+
+#[cfg(test)]
+mod tests {
+    use super::term_features_has_progress;
+
+    #[test]
+    fn term_features_progress_detection() {
+        // With PROGRESS feature ("P")
+        assert!(term_features_has_progress("MBT2ScP"));
+
+        // Without PROGRESS feature
+        assert!(!term_features_has_progress("MBT2Sc"));
+    }
+}