Replace some of our use of polars (#4801)

### What
* Part of #4789

We're using polars for some tests.
This PR replaces polars with our own data tables for the tests.


https://github.com/rerun-io/rerun/blob/main/crates/re_data_store/tests/data_store.rs
is left, and a pain in the ass.

### Checklist
* [x] I have read and agree to [Contributor
Guide](https://github.com/rerun-io/rerun/blob/main/CONTRIBUTING.md) and
the [Code of
Conduct](https://github.com/rerun-io/rerun/blob/main/CODE_OF_CONDUCT.md)
* [x] I've included a screenshot or gif (if applicable)
* [x] I have tested the web demo (if applicable):
* Using newly built examples:
[app.rerun.io](https://app.rerun.io/pr/4801/index.html)
* Using examples from latest `main` build:
[app.rerun.io](https://app.rerun.io/pr/4801/index.html?manifest_url=https://app.rerun.io/version/main/examples_manifest.json)
* Using full set of examples from `nightly` build:
[app.rerun.io](https://app.rerun.io/pr/4801/index.html?manifest_url=https://app.rerun.io/version/nightly/examples_manifest.json)
* [x] The PR title and labels are set such as to maximize their
usefulness for the next release's CHANGELOG

- [PR Build Summary](https://build.rerun.io/pr/4801)
- [Docs
preview](https://rerun.io/preview/5f0bfe1996e12b974d6ed306977628e8e9572386/docs)
<!--DOCS-PREVIEW-->
- [Examples
preview](https://rerun.io/preview/5f0bfe1996e12b974d6ed306977628e8e9572386/examples)
<!--EXAMPLES-PREVIEW-->
- [Recent benchmark results](https://build.rerun.io/graphs/crates.html)
- [Wasm size tracking](https://build.rerun.io/graphs/sizes.html)

---------

Co-authored-by: Clement Rey <[email protected]>

crates/re_data_store/src/store_dump.rs

@@ -2,7 +2,7 @@ use std::collections::BTreeMap;
 
 use arrow2::Either;
 use re_log_types::{
-    DataCellColumn, DataTable, ErasedTimeVec, RowIdVec, TableId, TimeRange, Timeline,
+    DataCellColumn, DataRow, DataTable, ErasedTimeVec, RowIdVec, TableId, TimeRange, Timeline,
 };
 
 use crate::{
@@ -13,13 +13,14 @@ use crate::{
 // ---
 
 impl DataStore {
-    /// Serializes the entire datastore into one big sorted [`DataTable`].
+    /// Serializes the entire datastore into one big sorted list of [`DataRow`].
     ///
     /// Individual [`re_log_types::DataRow`]s that were split apart due to bucketing are merged back together.
     ///
     /// Beware: this is extremely costly, don't use this in hot paths.
-    pub fn to_data_table(&self) -> re_log_types::DataReadResult<DataTable> {
-        use re_log_types::{DataRow, RowId};
+    pub fn to_rows(&self) -> re_log_types::DataReadResult<Vec<DataRow>> {
+        use re_log_types::RowId;
+        re_tracing::profile_function!();
 
         let mut rows = ahash::HashMap::<RowId, DataRow>::default();
         for table in self.to_data_tables(None) {
@@ -39,7 +40,23 @@ impl DataStore {
         }
 
         let mut rows = rows.into_values().collect::<Vec<_>>();
-        rows.sort_by_key(|row| (row.timepoint.clone(), row.row_id));
+        {
+            re_tracing::profile_scope!("sort_rows");
+            rows.sort_by_key(|row| (row.timepoint.clone(), row.row_id));
+        }
+
+        Ok(rows)
+    }
+
+    /// Serializes the entire datastore into one big sorted [`DataTable`].
+    ///
+    /// Individual [`re_log_types::DataRow`]s that were split apart due to bucketing are merged back together.
+    ///
+    /// Beware: this is extremely costly, don't use this in hot paths.
+    pub fn to_data_table(&self) -> re_log_types::DataReadResult<DataTable> {
+        re_tracing::profile_function!();
+
+        let rows = self.to_rows()?;
 
         Ok(re_log_types::DataTable::from_rows(
             re_log_types::TableId::new(),

crates/re_data_store/tests/correctness.rs

@@ -552,11 +552,8 @@ fn gc_correct() {
     check_still_readable(&store);
 }
 
-fn check_still_readable(_store: &DataStore) {
-    #[cfg(feature = "polars")]
-    {
-        _ = _store.to_dataframe(); // simple way of checking that everything is still readable
-    }
+fn check_still_readable(store: &DataStore) {
+    store.to_data_table().unwrap(); // simple way of checking that everything is still readable
 }
 
 // This used to panic because the GC will decrement the metadata_registry size trackers before

crates/re_data_store/tests/dump.rs

@@ -8,7 +8,9 @@ use re_data_store::{
     test_row, test_util::sanity_unwrap, DataStore, DataStoreStats, GarbageCollectionOptions,
     TimeInt, TimeRange, Timeline,
 };
-use re_log_types::{build_frame_nr, build_log_time, DataTable, EntityPath, TableId};
+use re_log_types::{
+    build_frame_nr, build_log_time, DataRow, DataTable, EntityPath, RowId, TableId,
+};
 use re_types::components::InstanceKey;
 use re_types::datagen::{build_some_colors, build_some_instances, build_some_positions2d};
 use re_types_core::Loggable as _;
@@ -31,6 +33,58 @@ fn insert_table_with_retries(store: &mut DataStore, table: &DataTable) {
     }
 }
 
+// Panic on RowId clash.
+fn insert_table(store: &mut DataStore, table: &DataTable) {
+    for row in table.to_rows() {
+        let row = row.unwrap();
+        store.insert_row(&row).unwrap();
+    }
+}
+
+// ---
+
+/// Allows adding more data to the same `RowId`.
+#[derive(Default)]
+struct RowSet(ahash::HashMap<RowId, DataRow>);
+
+impl RowSet {
+    fn insert_tables(&mut self, tables: impl Iterator<Item = DataTable>) {
+        for table in tables {
+            self.insert_table(&table);
+        }
+    }
+
+    fn insert_table(&mut self, table: &DataTable) {
+        for row in table.to_rows() {
+            self.insert_row(row.unwrap());
+        }
+    }
+
+    fn insert_row(&mut self, row: re_log_types::DataRow) {
+        match self.0.entry(row.row_id()) {
+            std::collections::hash_map::Entry::Occupied(mut entry) => {
+                assert_eq!(entry.get().entity_path(), row.entity_path());
+                assert_eq!(entry.get().cells(), row.cells());
+                assert_eq!(entry.get().num_instances(), row.num_instances());
+                for (timeline, time) in row.timepoint() {
+                    entry.get_mut().timepoint.insert(*timeline, *time);
+                }
+            }
+            std::collections::hash_map::Entry::Vacant(entry) => {
+                entry.insert(row);
+            }
+        }
+    }
+
+    fn insert_into(self, store: &mut DataStore) {
+        let mut rows = self.0.into_values().collect::<Vec<_>>();
+        rows.sort_by_key(|row| (row.timepoint.clone(), row.row_id));
+        for row in rows {
+            store.insert_row(&row).unwrap();
+        }
+    }
+}
+
 // --- Dump ---
 
 #[test]
@@ -69,17 +123,6 @@ fn data_store_dump() {
 }
 
 fn data_store_dump_impl(store1: &mut DataStore, store2: &mut DataStore, store3: &mut DataStore) {
-    // helper to insert a table both as a temporal and timeless payload
-    let insert_table = |store: &mut DataStore, table: &DataTable| {
-        // insert temporal
-        insert_table_with_retries(store, table);
-
-        // insert timeless
-        let mut table_timeless = table.clone();
-        table_timeless.col_timelines = Default::default();
-        insert_table_with_retries(store, &table_timeless);
-    };
-
     let ent_paths = ["this/that", "other", "yet/another/one"];
     let tables = ent_paths
         .iter()
@@ -88,34 +131,45 @@ fn data_store_dump_impl(store1: &mut DataStore, store2: &mut DataStore, store3:
 
     // Fill the first store.
     for table in &tables {
+        // insert temporal
         insert_table(store1, table);
+
+        // insert timeless
+        let mut table_timeless = table.clone();
+        table_timeless.col_timelines = Default::default();
+        insert_table_with_retries(store1, &table_timeless);
     }
     sanity_unwrap(store1);
 
     // Dump the first store into the second one.
-    for table in store1.to_data_tables(None) {
-        insert_table_with_retries(store2, &table);
+    {
+        // We use a RowSet instead of a DataTable to handle duplicate RowIds.
+        let mut row_set = RowSet::default();
+        row_set.insert_tables(store1.to_data_tables(None));
+        row_set.insert_into(store2);
+        sanity_unwrap(store2);
     }
-    sanity_unwrap(store2);
 
     // Dump the second store into the third one.
-    for table in store2.to_data_tables(None) {
-        insert_table_with_retries(store3, &table);
+    {
+        let mut row_set = RowSet::default();
+        row_set.insert_tables(store2.to_data_tables(None));
+        row_set.insert_into(store3);
+        sanity_unwrap(store3);
     }
-    sanity_unwrap(store3);
 
-    #[cfg(feature = "polars")]
     {
-        let store1_df = store1.to_dataframe();
-        let store2_df = store2.to_dataframe();
-        let store3_df = store3.to_dataframe();
+        let table_id = TableId::new(); // Reuse TableId so == works
+        let table1 = DataTable::from_rows(table_id, store1.to_rows().unwrap());
+        let table2 = DataTable::from_rows(table_id, store2.to_rows().unwrap());
+        let table3 = DataTable::from_rows(table_id, store3.to_rows().unwrap());
         assert!(
-            store1_df == store2_df,
-            "First & second stores differ:\n{store1_df}\n{store2_df}"
+            table1 == table2,
+            "First & second stores differ:\n{table1}\n{table2}"
         );
         assert!(
-            store1_df == store3_df,
-            "First & third stores differ:\n{store1_df}\n{store3_df}"
+            table1 == table3,
+            "First & third stores differ:\n{table1}\n{table3}"
         );
     }
 
@@ -183,39 +237,45 @@ fn data_store_dump_filtered_impl(store1: &mut DataStore, store2: &mut DataStore)
 
     // Fill the first store.
     for table in &tables {
-        insert_table_with_retries(store1, table);
+        insert_table(store1, table);
     }
     sanity_unwrap(store1);
 
-    // Dump frame1 from the first store into the second one.
-    for table in store1.to_data_tables((timeline_frame_nr, TimeRange::new(frame1, frame1)).into()) {
-        insert_table_with_retries(store2, &table);
-    }
-    // Dump frame2 from the first store into the second one.
-    for table in store1.to_data_tables((timeline_frame_nr, TimeRange::new(frame2, frame2)).into()) {
-        insert_table_with_retries(store2, &table);
-    }
-    // Dump frame3 from the first store into the second one.
-    for table in store1.to_data_tables((timeline_frame_nr, TimeRange::new(frame3, frame3)).into()) {
-        insert_table_with_retries(store2, &table);
-    }
-    // Dump the other frame3 from the first store into the second one.
-    for table in store1.to_data_tables((timeline_log_time, TimeRange::new(frame3, frame3)).into()) {
-        insert_table_with_retries(store2, &table);
-    }
-    // Dump frame4 from the first store into the second one.
-    for table in store1.to_data_tables((timeline_frame_nr, TimeRange::new(frame4, frame4)).into()) {
-        insert_table_with_retries(store2, &table);
-    }
+    // We use a RowSet instead of a DataTable to handle duplicate RowIds.
+    let mut row_set = RowSet::default();
+
+    // Dump frame1 from the first store.
+    row_set.insert_tables(
+        store1.to_data_tables((timeline_frame_nr, TimeRange::new(frame1, frame1)).into()),
+    );
+    // Dump frame2 from the first store.
+    row_set.insert_tables(
+        store1.to_data_tables((timeline_frame_nr, TimeRange::new(frame2, frame2)).into()),
+    );
+    // Dump frame3 from the first store.
+    row_set.insert_tables(
+        store1.to_data_tables((timeline_frame_nr, TimeRange::new(frame3, frame3)).into()),
+    );
+    // Dump frame3 _from the other timeline_, from the first store.
+    // This will produce the same RowIds again!
+    row_set.insert_tables(
+        store1.to_data_tables((timeline_log_time, TimeRange::new(frame3, frame3)).into()),
+    );
+    // Dump frame4 from the first store.
+    row_set.insert_tables(
+        store1.to_data_tables((timeline_frame_nr, TimeRange::new(frame4, frame4)).into()),
+    );
+
+    row_set.insert_into(store2);
     sanity_unwrap(store2);
 
-    #[cfg(feature = "polars")]
     {
-        let store1_df = store1.to_dataframe();
-        let store2_df = store2.to_dataframe();
+        let table_id = TableId::new(); // Reuse TableId so == works
+        let table1 = DataTable::from_rows(table_id, store1.to_rows().unwrap());
+        let table2 = DataTable::from_rows(table_id, store2.to_rows().unwrap());
         assert!(
-            store1_df == store2_df,
-            "First & second stores differ:\n{store1_df}\n{store2_df}"
+            table1 == table2,
+            "First & second stores differ:\n{table1}\n{table2}"
         );
     }
 

crates/re_log_types/src/data_cell.rs

@@ -138,7 +138,7 @@ impl PartialEq for DataCell {
 /// virtual calls.
 ///
 /// See #1746 for details.
-#[derive(Debug, Clone, PartialEq)]
+#[derive(Debug, Clone)]
 pub struct DataCellInner {
     /// Name of the component type used in this cell.
     //
@@ -163,6 +163,19 @@ pub struct DataCellInner {
     pub(crate) values: Box<dyn arrow2::array::Array>,
 }
 
+impl PartialEq for DataCellInner {
+    #[inline]
+    fn eq(&self, rhs: &Self) -> bool {
+        let Self {
+            name,
+            size_bytes: _, // we ignore the size (it may be 0 = uncomputed)
+            values,
+        } = self;
+
+        name == &rhs.name && values.eq(&rhs.values)
+    }
+}
+
 // TODO(#1696): We shouldn't have to specify the component name separately, this should be
 // part of the metadata by using an extension.
 // TODO(#1696): Check that the array is indeed a leaf / component type when building a cell from an

crates/re_log_types/src/example_components.rs

@@ -4,6 +4,7 @@ use re_types_core::{Loggable, SizeBytes};
 
 // ----------------------------------------------------------------------------
 
+#[derive(Debug)]
 pub struct MyPoints;
 
 impl re_types_core::Archetype for MyPoints {

crates/re_query/Cargo.toml

@@ -39,6 +39,7 @@ arrow2.workspace = true
 backtrace.workspace = true
 document-features.workspace = true
 itertools = { workspace = true }
+smallvec.workspace = true
 thiserror.workspace = true
 
 # Optional dependencies:

crates/re_query/src/archetype_view.rs

@@ -2,7 +2,7 @@ use std::{collections::BTreeMap, marker::PhantomData};
 
 use arrow2::array::{Array, PrimitiveArray};
 use re_format::arrow;
-use re_log_types::{DataCell, RowId};
+use re_log_types::{DataCell, DataCellRow, RowId};
 use re_types_core::{
     components::InstanceKey, Archetype, Component, ComponentName, DeserializationError,
     DeserializationResult, Loggable, SerializationResult,
@@ -116,6 +116,15 @@ impl ComponentWithInstances {
             values: DataCell::from_arrow(C::name(), values),
         })
     }
+
+    #[inline]
+    pub fn into_data_cell_row(self) -> DataCellRow {
+        let Self {
+            instance_keys,
+            values,
+        } = self;
+        DataCellRow(smallvec::smallvec![instance_keys, values])
+    }
 }
 
 /// Iterator over a single [`Component`] joined onto a primary [`Component`]
@@ -519,6 +528,32 @@ impl<A: Archetype> ArchetypeView<A> {
                 .map(|comp| (comp.name(), comp.values.to_arrow())),
         )?)
     }
+
+    /// Useful for tests.
+    pub fn to_data_cell_row_1<
+        'a,
+        C1: re_types_core::Component + Clone + Into<::std::borrow::Cow<'a, C1>> + 'a,
+    >(
+        &self,
+    ) -> crate::Result<DataCellRow> {
+        let cell0 = DataCell::from_native(self.iter_instance_keys());
+        let cell1 = DataCell::from_native_sparse(self.iter_optional_component::<C1>()?);
+        Ok(DataCellRow(smallvec::smallvec![cell0, cell1]))
+    }
+
+    /// Useful for tests.
+    pub fn to_data_cell_row_2<
+        'a,
+        C1: re_types_core::Component + Clone + Into<::std::borrow::Cow<'a, C1>> + 'a,
+        C2: re_types_core::Component + Clone + Into<::std::borrow::Cow<'a, C2>> + 'a,
+    >(
+        &self,
+    ) -> crate::Result<DataCellRow> {
+        let cell0 = DataCell::from_native(self.iter_instance_keys());
+        let cell1 = DataCell::from_native_sparse(self.iter_optional_component::<C1>()?);
+        let cell2 = DataCell::from_native_sparse(self.iter_optional_component::<C2>()?);
+        Ok(DataCellRow(smallvec::smallvec![cell0, cell1, cell2]))
+    }
 }
 
 #[test]