[arrow-rs] branch master updated: Trim parquet row selection (#2705)

[tustvold]

This is an automated email from the ASF dual-hosted git repository.

tustvold pushed a commit to branch master
in repository https://gitbox.apache.org/repos/asf/arrow-rs.git


The following commit(s) were added to refs/heads/master by this push:
     new 7c8080c67 Trim parquet row selection (#2705)
7c8080c67 is described below

commit 7c8080c6752a55256630f6f6e6c82bf8a540d20b
Author: Raphael Taylor-Davies <1781103+tustv...@users.noreply.github.com>
AuthorDate: Sat Sep 24 17:20:49 2022 +0100

    Trim parquet row selection (#2705)
---
 parquet/src/arrow/arrow_reader/mod.rs       | 2 +-
 parquet/src/arrow/arrow_reader/selection.rs | 8 ++++++++
 2 files changed, 9 insertions(+), 1 deletion(-)

diff --git a/parquet/src/arrow/arrow_reader/mod.rs 
b/parquet/src/arrow/arrow_reader/mod.rs
index b00afc475..59abf9ad8 100644
--- a/parquet/src/arrow/arrow_reader/mod.rs
+++ b/parquet/src/arrow/arrow_reader/mod.rs
@@ -570,7 +570,7 @@ impl ParquetRecordBatchReader {
             batch_size,
             array_reader,
             schema: Arc::new(schema),
-            selection: selection.map(Into::into),
+            selection: selection.map(|s| s.trim().into()),
         }
     }
 }
diff --git a/parquet/src/arrow/arrow_reader/selection.rs 
b/parquet/src/arrow/arrow_reader/selection.rs
index 495e346e0..6a965dc9b 100644
--- a/parquet/src/arrow/arrow_reader/selection.rs
+++ b/parquet/src/arrow/arrow_reader/selection.rs
@@ -285,6 +285,14 @@ impl RowSelection {
     pub fn selects_any(&self) -> bool {
         self.selectors.iter().any(|x| !x.skip)
     }
+
+    /// Trims this [`RowSelection`] removing any trailing skips
+    pub(crate) fn trim(mut self) -> Self {
+        while self.selectors.last().map(|x| x.skip).unwrap_or(false) {
+            self.selectors.pop();
+        }
+        self
+    }
 }
 
 impl From<Vec<RowSelector>> for RowSelection {