vcf/io/writer/record/info/field/value/integer: Validate value

Integer values must now be > -2^31 + 7. See _The Variant Call Format
Specification: VCFv4.5 and BCFv2.2_ (2024-06-28) § 1.3 "Data types".

noodles-vcf/CHANGELOG.md

@@ -1,5 +1,14 @@
 # Changelog
 
+## Unreleased
+
+### Changed
+
+  * vcf/io/writer/record/info/field/value/integer: Validate value.
+
+    Integer values must now be > -2^31 + 7. See _The Variant Call Format
+    Specification: VCFv4.5 and BCFv2.2_ (2024-06-28) § 1.3 "Data types".
+
 ## 0.65.0 - 2024-09-12
 
 ### Changed

noodles-vcf/src/io/writer/record/info/field/value/integer.rs

@@ -4,7 +4,21 @@ pub(super) fn write_integer<W>(writer: &mut W, n: i32) -> io::Result<()>
 where
     W: Write,
 {
-    write!(writer, "{n}")
+    if is_valid(n) {
+        write!(writer, "{n}")
+    } else {
+        Err(io::Error::new(
+            io::ErrorKind::InvalidInput,
+            "invalid integer",
+        ))
+    }
+}
+
+// § 1.3 "Data types" (2024-06-28): "For the Integer type, the values from -2^31 to -2^31 + 7
+// cannot be stored in the binary version and therefore are disallowed in both VCF and BCF..."
+fn is_valid(n: i32) -> bool {
+    const MIN: i32 = i32::MIN + 7;
+    n > MIN
 }
 
 #[cfg(test)]
@@ -22,10 +36,16 @@ mod tests {
 
         let mut buf = Vec::new();
 
-        t(&mut buf, i32::MIN, b"-2147483648")?;
+        t(&mut buf, i32::MIN + 8, b"-2147483640")?;
         t(&mut buf, 0, b"0")?;
         t(&mut buf, i32::MAX, b"2147483647")?;
 
+        buf.clear();
+        assert!(matches!(
+            write_integer(&mut buf, i32::MIN),
+            Err(e) if e.kind() == io::ErrorKind::InvalidInput
+        ));
+
         Ok(())
     }
 }