rpc: scriptPubKey type is nonstandard for a v0 witness program of another length

changelog.d/scriptpubkey-witness-v0-type.md

@@ -0,0 +1,8 @@
+Fixed
+
+- **`scriptPubKey` `type` is `nonstandard` for a version 0 witness
+  program that is neither 20 nor 32 bytes, as in Core.** A version 0
+  program is a key hash at 20 bytes and a script hash at 32. Any other
+  length, such as `0003abcdef`, was `witness_unknown`. It is now
+  `nonstandard`. Versions 1 to 16 that are not taproot or an anchor stay
+  `witness_unknown`.

crates/rbitcoin-rpc/src/methods/mine.rs

@@ -85,8 +85,12 @@ pub fn script_core_type(script: &bitcoin::Script) -> &'static str {
         "witness_v1_taproot"
     } else if is_p2anchor(script) {
         "anchor"
-    } else if script.is_witness_program() {
-        "witness_unknown"
+    } else if let Some(version) = script.witness_version() {
+        if version == bitcoin::WitnessVersion::V0 {
+            "nonstandard"
+        } else {
+            "witness_unknown"
+        }
     } else if script.is_op_return() {
         "nulldata"
     } else if script.is_p2pk() {

crates/rbitcoin-rpc/tests/methods/mod.rs

@@ -430,6 +430,28 @@ fn decodescript_multisig_type_matches_core() {
     let _ = std::fs::remove_dir_all(&dir);
 }
 
+#[test]
+fn decodescript_witness_program_type_matches_core() {
+    let program = |version: &str, len: usize| format!("{version}{len:02x}{}", "ab".repeat(len));
+    let rows = [
+        (program("00", 2), "nonstandard"),
+        (program("00", 21), "nonstandard"),
+        (program("00", 40), "nonstandard"),
+        (program("00", 20), "witness_v0_keyhash"),
+        (program("00", 32), "witness_v0_scripthash"),
+        (program("51", 2), "witness_unknown"),
+        ("51024e73".into(), "anchor"),
+        (program("60", 40), "witness_unknown"),
+        (program("51", 41), "nonstandard"),
+    ];
+    let (ctx, dir) = ctx_empty();
+    for (hex, ty) in &rows {
+        let script = dispatch(&ctx, "decodescript", vec![json!(hex)]).unwrap();
+        assert_eq!(script["type"], json!(ty), "{hex}");
+    }
+    let _ = std::fs::remove_dir_all(&dir);
+}
+
 #[test]
 fn help_and_getrpcinfo_list_methods() {
     let (ctx, dir) = ctx_empty();