expose and features

crates/polars-lazy/src/frame/mod.rs

@@ -153,6 +153,13 @@ impl LazyFrame {
         self
     }
 
+    /// Check if operations are order dependent and unset maintaining_order if
+    /// the order would not be observed.
+    pub fn with_check_order(mut self, toggle: bool) -> Self {
+        self.opt_state.set(OptFlags::CHECK_ORDER_OBSERVE, toggle);
+        self
+    }
+
     /// Toggle predicate pushdown optimization.
     pub fn with_predicate_pushdown(mut self, toggle: bool) -> Self {
         self.opt_state.set(OptFlags::PREDICATE_PUSHDOWN, toggle);

crates/polars-plan/src/frame/opt_state.rs

@@ -35,6 +35,9 @@ bitflags! {
         const FAST_PROJECTION = 1 << 14;
         /// Collapse slower joins with filters into faster joins.
         const COLLAPSE_JOINS = 1 << 15;
+        /// Check if operations are order dependent and unset maintaining_order if
+        /// the order would not be observed.
+        const CHECK_ORDER_OBSERVE = 1 << 16;
     }
 }
 

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

@@ -210,7 +210,9 @@ pub fn optimize(
         cache_states::set_cache_states(lp_top, lp_arena, expr_arena, scratch, expr_eval, verbose)?;
     }
 
-    if members.has_group_by | members.has_sort | members.has_distinct {
+    if opt_state.contains(OptFlags::CHECK_ORDER_OBSERVE)
+        && members.has_group_by | members.has_sort | members.has_distinct
+    {
         set_order_flags(lp_top, lp_arena, expr_arena, scratch);
     }
 

crates/polars-plan/src/plans/optimizer/set_order.rs

@@ -105,8 +105,8 @@ pub(super) fn set_order_flags(
 
                 if apply.is_some()
                     || *maintain_order
-                    || options.rolling.is_some()
-                    || options.dynamic.is_some()
+                    || options.is_rolling()
+                    || options.is_dynamic()
                 {
                     maintain_order_above = true;
                     continue;

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

@@ -72,6 +72,30 @@ pub struct GroupbyOptions {
     pub slice: Option<(i64, usize)>,
 }
 
+impl GroupbyOptions {
+    pub(crate) fn is_rolling(&self) -> bool {
+        #[cfg(feature = "dynamic_group_by")]
+        {
+            self.rolling.is_some()
+        }
+        #[cfg(not(feature = "dynamic_group_by"))]
+        {
+            false
+        }
+    }
+
+    pub(crate) fn is_dynamic(&self) -> bool {
+        #[cfg(feature = "dynamic_group_by")]
+        {
+            self.dynamic.is_some()
+        }
+        #[cfg(not(feature = "dynamic_group_by"))]
+        {
+            false
+        }
+    }
+}
+
 #[derive(Clone, Debug, Eq, PartialEq, Default, Hash)]
 #[cfg_attr(feature = "serde", derive(Serialize, Deserialize))]
 pub struct DistinctOptionsDSL {

crates/polars-python/src/lazyframe/general.rs

@@ -494,6 +494,7 @@ impl PyLazyFrame {
         collapse_joins: bool,
         streaming: bool,
         _eager: bool,
+        _check_order: bool,
         #[allow(unused_variables)] new_streaming: bool,
     ) -> Self {
         let ldf = self.ldf.clone();
@@ -504,6 +505,7 @@ impl PyLazyFrame {
             .with_slice_pushdown(slice_pushdown)
             .with_cluster_with_columns(cluster_with_columns)
             .with_collapse_joins(collapse_joins)
+            .with_check_order(_check_order)
             ._with_eager(_eager)
             .with_projection_pushdown(projection_pushdown);
 

py-polars/polars/lazyframe/frame.py

@@ -986,7 +986,7 @@ def skip_minmax(dt: PolarsDataType) -> bool:
         # reshape wide result
         n_metrics = len(metrics)
         column_metrics = [
-            df_metrics.row(0)[(n * n_metrics) : (n + 1) * n_metrics]
+            df_metrics.row(0)[(n * n_metrics): (n + 1) * n_metrics]
             for n in range(schema.len())
         ]
         summary = dict(zip(schema, column_metrics))
@@ -1768,6 +1768,7 @@ def collect(
         engine: EngineType = "cpu",
         background: Literal[True],
         _eager: bool = False,
+        _check_order: bool = True,
     ) -> InProcessQuery: ...
 
     @overload
@@ -1787,6 +1788,7 @@ def collect(
         streaming: bool = False,
         engine: EngineType = "cpu",
         background: Literal[False] = False,
+        _check_order: bool = True,
         _eager: bool = False,
     ) -> DataFrame: ...
 
@@ -1806,6 +1808,7 @@ def collect(
         streaming: bool = False,
         engine: EngineType = "cpu",
         background: bool = False,
+        _check_order: bool = True,
         _eager: bool = False,
         **_kwargs: Any,
     ) -> DataFrame | InProcessQuery:
@@ -1974,6 +1977,7 @@ def collect(
             comm_subexpr_elim = False
             cluster_with_columns = False
             collapse_joins = False
+            _check_order = False
 
         if streaming:
             issue_unstable_warning("Streaming mode is considered unstable.")
@@ -2005,6 +2009,7 @@ def collect(
             collapse_joins,
             streaming,
             _eager,
+            _check_order,
             new_streaming,
         )