Method with_reads

datafusion/datasource/src/file_stream/mod.rs:1428–1431

Sets the partition polling order. `run()` polls these partitions in the listed order first. After those explicit reads are exhausted, it completes to round robin across all configured partitions, skipping any streams that have already finished. This allows testing early scheduling decisions explicit in a test while avoiding a fully scripted poll trace for the remainder.

(mut self, reads: Vec<PartitionId>)

        /// This allows testing early scheduling decisions explicit in a test
        /// while avoiding a fully scripted poll trace for the remainder.
        fn with_reads(mut self, reads: Vec<PartitionId>) -> Self {
            self.reads = reads;
            self
        }

        /// Sets a global output limit for all streams created by this test.
        fn with_limit(mut self, limit: usize) -> Self {