Introduce static hex and valid signature for block test.

substrate/wasm-runtime/polkadot/src/support/statichex.rs

@@ -0,0 +1,29 @@
+use rustc_hex::FromHex;
+
+pub trait StaticHexConversion: Sized {
+	fn from_static_hex(hex: &'static str) -> Self;
+}
+
+macro_rules! impl_sizes {
+	( $( $t:expr ),* ) => { $(
+		impl StaticHexConversion for [u8; $t] {
+			fn from_static_hex(hex: &'static str) -> Self {
+				let mut r = [0u8; $t];
+				r.copy_from_slice(&FromHex::from_hex(hex).unwrap());
+				r
+			}
+		}
+	)* }
+}
+
+impl_sizes!(1, 2, 3, 4, 5, 6, 7, 8, 10, 12, 14, 16, 20, 24, 28, 32, 40, 48, 56, 64, 80, 96, 112, 128);
+
+pub trait StaticHexInto {
+	fn convert<T: StaticHexConversion>(self) -> T;
+}
+
+impl StaticHexInto for &'static str {
+	fn convert<T: StaticHexConversion>(self) -> T {
+		T::from_static_hex(self)
+	}
+}