gate eprintln calls for no_std

src/buffer.rs

@@ -755,11 +755,18 @@ impl RawBuffer {
 
 impl Drop for PyUntypedBuffer {
     fn drop(&mut self) {
-        if Python::try_attach(|_| unsafe { self.0.release() }).is_none()
-            && crate::internal::state::is_in_gc_traversal()
-        {
-            eprintln!("Warning: PyBuffer dropped while in GC traversal, this is a bug and will leak memory.");
+        #[cfg_attr(not(wip_feature_std), expect(unused_variables))]
+        let released = Python::try_attach(|_| unsafe {
+            self.0.release();
+        })
+        .is_some();
+
+        // TODO remove once implementing GC traversal is unsafe
+        #[cfg(wip_feature_std)]
+        if !released && crate::internal::state::is_in_gc_traversal() {
+            std::eprintln!("Warning: PyBuffer dropped while in GC traversal, this is a bug and will leak memory.");
         }
+
         // If `try_attach` failed and `is_in_gc_traversal()` is false, then probably the interpreter has
         // already finalized and we can just assume that the underlying memory has already been freed.
         //

src/conversions/jiff.rs

@@ -781,10 +781,6 @@ mod tests {
                 |name: &'static str, year, month, day, hour, minute, second, ms, py_ms| {
                     let offset = Offset::from_seconds(3600).unwrap();
                     let datetime = DateTime::new(year, month, day, hour, minute, second, ms * 1000)
-                        .map_err(|e| {
-                            eprintln!("{name}: {e}");
-                            e
-                        })
                         .unwrap()
                         .to_zoned(offset.to_time_zone())
                         .unwrap();

src/err/mod.rs

@@ -305,8 +305,10 @@ impl PyErr {
             .map(|py_str| py_str.to_string_lossy().into())
             .unwrap_or_else(|_| String::from("Unwrapped panic from Python code"));
 
-        eprintln!("--- PyO3 is resuming a panic after fetching a PanicException from Python. ---");
-        eprintln!("Python stack trace below:");
+        std::eprintln!(
+            "--- PyO3 is resuming a panic after fetching a PanicException from Python. ---"
+        );
+        std::eprintln!("Python stack trace below:");
 
         PyErrState::normalized(state).restore(py);
 

src/internal/state.rs

@@ -367,6 +367,7 @@ pub fn register_decref(obj: Py<PyAny>) {
 
 /// Private helper function to check if we are currently in a GC traversal (as detected by PyO3).
 #[cfg(any(not(Py_LIMITED_API), Py_3_11))]
+#[cfg_attr(not(wip_feature_std), expect(dead_code))] // keep code if not used to minimize refactoring friction
 pub(crate) fn is_in_gc_traversal() -> bool {
     ATTACH_COUNT
         .try_with(|c| c.get() == ATTACH_FORBIDDEN_DURING_TRAVERSE)

src/platform.rs

@@ -10,9 +10,6 @@ pub(crate) mod prelude {
         string::{String, ToString},
         vec::Vec,
     };
-
-    // TODO find a `no_std` replacement for eprintln
-    pub use std::eprintln;
 }
 
 pub mod sync;