Merge rust-bitcoin/rust-bitcoin#3324: Add tests for witness_program

733505148c Add tests for witness_program (Shing Him Ng)

Pull request description:

  Add tests for witness_program

ACKs for top commit:
  tcharding:
    ACK 733505148c
  Kixunil:
    ACK 733505148c
  apoelstra:
    ACK 733505148c successfully ran local tests

Tree-SHA512: c1ee82edf22c7b39bc110d03836ba5ebfa785a63185a75c1a61781180ff907c1ea0c491c963629450f360152766845dacedccc6cf56bc3d8c607e66281427dd3

bitcoin/src/blockdata/script/witness_program.rs

@@ -164,3 +164,45 @@ impl std::error::Error for Error {
         }
     }
 }
+
+#[cfg(test)]
+mod tests {
+    use super::*;
+
+    #[test]
+    fn witness_program_is_too_short() {
+        let arbitrary_bytes = [0x00; MIN_SIZE - 1];
+        assert!(WitnessProgram::new(WitnessVersion::V15, &arbitrary_bytes).is_err()); // Arbitrary version
+    }
+
+    #[test]
+    fn witness_program_is_too_long() {
+        let arbitrary_bytes = [0x00; MAX_SIZE + 1];
+        assert!(WitnessProgram::new(WitnessVersion::V15, &arbitrary_bytes).is_err()); // Arbitrary version
+    }
+
+    #[test]
+    fn valid_v0_witness_programs() {
+        let arbitrary_bytes = [0x00; MAX_SIZE];
+
+        for size in MIN_SIZE..=MAX_SIZE {
+            let program = WitnessProgram::new(WitnessVersion::V0, &arbitrary_bytes[..size]);
+
+            if size == 20 {
+                assert!(program.expect("valid witness program").is_p2wpkh());
+                continue
+            }
+            if size == 32 {
+                assert!(program.expect("valid witness program").is_p2wsh());
+                continue
+            }
+            assert!(program.is_err());
+        }
+    }
+
+    #[test]
+    fn valid_v1_witness_programs() {
+        let arbitrary_bytes = [0x00; 32];
+        assert!(WitnessProgram::new(WitnessVersion::V1, &arbitrary_bytes).expect("valid witness program").is_p2tr());
+    }
+}