feat: Add Display trait for bcf::Record

src/bcf/record.rs

@@ -1237,6 +1237,25 @@ unsafe impl Send for Record {}
 
 unsafe impl Sync for Record {}
 
+impl fmt::Display for Record {
+    fn fmt(&self, f: &mut fmt::Formatter<'_>) -> fmt::Result {
+        let mut buf = htslib::kstring_t {
+            l: 0,
+            m: 0,
+            s: ptr::null_mut(),
+        };
+        let vcf_str = unsafe {
+            htslib::vcf_format(self.header().inner, self.inner, &mut buf);
+            let vcf_str = String::from(ffi::CStr::from_ptr(buf.s).to_str().unwrap());
+            if !buf.s.is_null() {
+                libc::free(buf.s as *mut libc::c_void);
+            }
+            vcf_str
+        };
+        write!(f, "{vcf_str}")
+    }
+}
+
 /// Info tag representation.
 #[derive(Debug)]
 pub struct Info<'a, B: BorrowMut<Buffer> + Borrow<Buffer>> {
@@ -1714,4 +1733,18 @@ mod tests {
         assert!(!record.has_filter(&bar));
         assert!(record.has_filter("PASS".as_bytes()));
     }
+
+    #[test]
+    fn test_record_display_trait() {
+        let tmp = NamedTempFile::new().unwrap();
+        let path = tmp.path();
+        let mut header = Header::new();
+        header.push_record(b"##contig=<ID=chr1,length=1000>");
+        header.push_record(br#"##FILTER=<ID=foo,Description="sample is a foo fighter">"#);
+        let vcf = Writer::from_path(path, &header, true, Format::Vcf).unwrap();
+        let mut record = vcf.empty_record();
+        record.push_filter("foo".as_bytes()).unwrap();
+        let s = format!("{record}");
+        assert_eq!(s, "chr1\t1\t.\t.\t.\t0\tfoo\t.\n");
+    }
 }