move impl to polars-time

crates/polars-plan/src/dsl/function_expr/business/business_day_count.rs

@@ -1,5 +1,6 @@
 use polars_core::chunked_array::ops::arity::binary_elementwise_values;
 use polars_core::prelude::*;
+use polars_time::business_day_count_impl;
 
 pub(super) fn business_day_count(s: &[Series]) -> PolarsResult<Series> {
     let start = &s[0];
@@ -16,7 +17,7 @@ pub(super) fn business_day_count(s: &[Series]) -> PolarsResult<Series> {
         (_, 1) => {
             if let Some(end_date) = end_dates.get(0) {
                 start_dates.apply_values(|start_date| {
-                    impl_business_day_count(
+                    business_day_count_impl(
                         start_date,
                         end_date,
                         &week_mask,
@@ -30,7 +31,7 @@ pub(super) fn business_day_count(s: &[Series]) -> PolarsResult<Series> {
         (1, _) => {
             if let Some(start_date) = start_dates.get(0) {
                 end_dates.apply_values(|end_date| {
-                    impl_business_day_count(
+                    business_day_count_impl(
                         start_date,
                         end_date,
                         &week_mask,
@@ -42,7 +43,7 @@ pub(super) fn business_day_count(s: &[Series]) -> PolarsResult<Series> {
             }
         },
         _ => binary_elementwise_values(start_dates, end_dates, |start_date, end_date| {
-            impl_business_day_count(
+            business_day_count_impl(
                 start_date,
                 end_date,
                 &week_mask,
@@ -52,48 +53,3 @@ pub(super) fn business_day_count(s: &[Series]) -> PolarsResult<Series> {
     };
     Ok(out.into_series())
 }
-
-/// Ported from:
-/// https://github.com/numpy/numpy/blob/e59c074842e3f73483afa5ddef031e856b9fd313/numpy/_core/src/multiarray/datetime_busday.c#L355-L433
-fn impl_business_day_count(
-    mut start_date: i32,
-    mut end_date: i32,
-    week_mask: &[bool; 7],
-    n_business_days_in_week_mask: i32,
-) -> i32 {
-    let swapped = start_date > end_date;
-    if swapped {
-        (start_date, end_date) = (end_date, start_date);
-        start_date += 1;
-        end_date += 1;
-    }
-
-    let mut start_weekday = weekday(start_date);
-    let diff = end_date - start_date;
-    let whole_weeks = diff / 7;
-    let mut count = 0;
-    count += whole_weeks * n_business_days_in_week_mask;
-    start_date += whole_weeks * 7;
-    while start_date < end_date {
-        if unsafe { *week_mask.get_unchecked(start_weekday) } {
-            count += 1;
-        }
-        start_date += 1;
-        start_weekday += 1;
-        if start_weekday >= 7 {
-            start_weekday = 0;
-        }
-    }
-    if swapped {
-        -count
-    } else {
-        count
-    }
-}
-
-pub(crate) fn weekday(x: i32) -> usize {
-    // the first modulo might return a negative number, so we add 7 and take
-    // the modulo again so we're sure we have something between 0 (Monday)
-    // and 6 (Sunday)
-    (((x - 4) % 7 + 7) % 7) as usize
-}

crates/polars-time/src/business.rs

@@ -0,0 +1,45 @@
+/// Ported from:
+/// https://github.com/numpy/numpy/blob/e59c074842e3f73483afa5ddef031e856b9fd313/numpy/_core/src/multiarray/datetime_busday.c#L355-L433
+#[doc(hidden)]
+pub fn business_day_count_impl(
+    mut start_date: i32,
+    mut end_date: i32,
+    week_mask: &[bool; 7],
+    n_business_days_in_week_mask: i32,
+) -> i32 {
+    let swapped = start_date > end_date;
+    if swapped {
+        (start_date, end_date) = (end_date, start_date);
+        start_date += 1;
+        end_date += 1;
+    }
+
+    let mut start_weekday = weekday(start_date);
+    let diff = end_date - start_date;
+    let whole_weeks = diff / 7;
+    let mut count = 0;
+    count += whole_weeks * n_business_days_in_week_mask;
+    start_date += whole_weeks * 7;
+    while start_date < end_date {
+        if unsafe { *week_mask.get_unchecked(start_weekday) } {
+            count += 1;
+        }
+        start_date += 1;
+        start_weekday += 1;
+        if start_weekday >= 7 {
+            start_weekday = 0;
+        }
+    }
+    if swapped {
+        -count
+    } else {
+        count
+    }
+}
+
+pub(crate) fn weekday(x: i32) -> usize {
+    // the first modulo might return a negative number, so we add 7 and take
+    // the modulo again so we're sure we have something between 0 (Monday)
+    // and 6 (Sunday)
+    (((x - 4) % 7 + 7) % 7) as usize
+}

crates/polars-time/src/lib.rs

@@ -1,5 +1,6 @@
 #![cfg_attr(docsrs, feature(doc_auto_cfg))]
 mod base_utc_offset;
+mod business;
 pub mod chunkedarray;
 mod date_range;
 mod dst_offset;
@@ -16,6 +17,7 @@ mod windows;
 
 #[cfg(feature = "timezones")]
 pub use base_utc_offset::*;
+pub use business::*;
 pub use date_range::*;
 #[cfg(feature = "timezones")]
 pub use dst_offset::*;