[feat] Check that read pairs have the same name

The read name checked include only the header line up to the first white-space.  The
remaining header is ignore.

src/lib/demux.rs

@@ -421,6 +421,20 @@ where
             let mut output_reads = vec![];
             let mut qual_counter = BaseQualCounter::new();
 
+            // Ensure that all the reads have the same read name
+            ensure!(!zipped_reads.is_empty(), "Bug: no records found");
+            let first_read_name =
+                zipped_reads[0].head().splitn(2, |c| *c == b' ').next().unwrap_or(b"");
+            for read in &zipped_reads {
+                let cur_read_name = read.head().splitn(2, |c| *c == b' ').next().unwrap_or(b"");
+                ensure!(
+                    first_read_name == cur_read_name,
+                    "Read names did not match: {:?} != {:?}",
+                    String::from_utf8_lossy(first_read_name),
+                    String::from_utf8_lossy(cur_read_name)
+                );
+            }
+
             // If any filtering was specified, check it here by peeking at the header of the first read in the set of reads.
             match self.apply_filters(&zipped_reads)? {
                 Some(ReadFailedFilterResult::ControlFilter) => {
@@ -1655,4 +1669,28 @@ mod test {
             "Sample2 R2 reads should match expected"
         );
     }
+
+    #[rstest]
+    #[rustfmt::skip]
+    fn test_demux_paired_reads_different_read_names(
+        #[values(MatcherKind::CachedHammingDistance, MatcherKind::PreCompute)]
+        matcher: MatcherKind
+    ) {
+        let read_structures = vec![
+            ReadStructure::from_str("8B100T").unwrap(),
+            ReadStructure::from_str("9B100T").unwrap(),
+        ];
+
+        let mut fq1: OwnedRecord= Fq { name: "frag1", bases: &[&SAMPLE_BARCODE_1[0..8], &[b'A'; 100]].concat(), ..Fq::default() }.to_owned_record();
+        let fq2 = Fq { name: "frag2", bases: &[&SAMPLE_BARCODE_1[8..],  &[b'T'; 100]].concat(), ..Fq::default() }.to_owned_record();
+
+        // mess with the FQ1 read name
+        fq1.head = vec![b'f'];
+        fq1.head.append(&mut fq2.head.clone());
+
+        let context = DemuxTestContext::demux_structures(vec![fq1, fq2], read_structures, matcher);
+        let demuxer = context.demux();
+        let result = demuxer.demultiplex(&context.per_fastq_record_set);
+        assert!(result.is_err());
+    }
 }