feat(rust): IR formatting QoL improvements (#20246)

crates/polars-plan/src/plans/ir/format.rs

@@ -417,6 +417,12 @@ impl Display for IRDisplay<'_> {
     }
 }
 
+impl fmt::Debug for IRDisplay<'_> {
+    fn fmt(&self, f: &mut Formatter<'_>) -> fmt::Result {
+        Display::fmt(&self, f)
+    }
+}
+
 impl<T: AsExpr> Display for ExprIRSliceDisplay<'_, T> {
     fn fmt(&self, f: &mut Formatter<'_>) -> fmt::Result {
         // Display items in slice delimited by a comma

crates/polars-plan/src/plans/ir/mod.rs

@@ -17,6 +17,7 @@ use polars_utils::unitvec;
 pub use scan_sources::{ScanSourceIter, ScanSourceRef, ScanSources};
 #[cfg(feature = "ir_serde")]
 use serde::{Deserialize, Serialize};
+use strum_macros::IntoStaticStr;
 
 use crate::prelude::*;
 
@@ -36,8 +37,9 @@ pub struct IRPlanRef<'a> {
 
 /// [`IR`] is a representation of [`DslPlan`] with [`Node`]s which are allocated in an [`Arena`]
 /// In this IR the logical plan has access to the full dataset.
-#[derive(Clone, Debug, Default)]
+#[derive(Clone, Debug, Default, IntoStaticStr)]
 #[cfg_attr(feature = "ir_serde", derive(Serialize, Deserialize))]
+#[strum(serialize_all = "SCREAMING_SNAKE_CASE")]
 pub enum IR {
     #[cfg(feature = "python")]
     PythonScan {

crates/polars-plan/src/plans/mod.rs

@@ -225,7 +225,7 @@ impl DslPlan {
         struct DslPlanDisplay(IRPlan);
         impl fmt::Display for DslPlanDisplay {
             fn fmt(&self, f: &mut fmt::Formatter<'_>) -> fmt::Result {
-                self.0.as_ref().display().fmt(f)
+                fmt::Display::fmt(&self.0.as_ref().display(), f)
             }
         }
         Ok(DslPlanDisplay(self.clone().to_alp()?))