fix clippy lints

Signed-off-by: Petros Angelatos <[email protected]>

Author: petrosagg

src/storage/src/render/persist_sink.rs

@@ -159,22 +159,6 @@ impl AddAssign<&BatchMetrics> for BatchMetrics {
     }
 }
 
-impl BatchMetrics {
-    fn is_empty(&self) -> bool {
-        let BatchMetrics {
-            inserts: self_inserts,
-            retractions: self_retractions,
-            error_inserts: self_error_inserts,
-            error_retractions: self_error_retractions,
-        } = self;
-
-        *self_inserts == 0
-            && *self_retractions == 0
-            && *self_error_inserts == 0
-            && *self_error_retractions == 0
-    }
-}
-
 /// Manages batches and metrics.
 struct BatchBuilderAndMetadata<K, V, T, D>
 where

src/storage/src/source.rs

@@ -40,6 +40,7 @@ pub use kafka::KafkaSourceReader;
 pub use source_reader_pipeline::{
     create_raw_source, RawSourceCreationConfig, SourceExportCreationConfig,
 };
+use mz_ore::cast::CastFrom;
 use timely::container::{PushInto, SizableContainer};
 use timely::dataflow::channels::pact::Pipeline;
 use timely::dataflow::operators::generic::builder_rc::OperatorBuilder;
@@ -78,8 +79,8 @@ impl<G: Scope, C: Container> PartitionCore<G, C> for StreamCore<G, C> {
         let mut builder = OperatorBuilder::new("Partition".to_owned(), self.scope());
 
         let mut input = builder.new_input(self, Pipeline);
-        let mut outputs = Vec::with_capacity(parts as usize);
-        let mut streams = Vec::with_capacity(parts as usize);
+        let mut outputs = Vec::with_capacity(usize::cast_from(parts));
+        let mut streams = Vec::with_capacity(usize::cast_from(parts));
 
         for _ in 0..parts {
             let (output, stream) = builder.new_output();