keyring: remove lazy_static public keys hash maps (#2387)

The `lazy_static` package does not work well in `no-std`: it requires
`spin_no_std` feature, which also will propagate into `std` if enabled.
This is not what we want.

This PR removes public/private key hash-maps and replaces them with
simple static byte arrays.

`&T` versions of `AsRef/Deref/From` traits implementation were removed.

Little const helper for converting hex strings into array during compile
time was also added. (somewhat similar to _hex_literal_).

---------

Co-authored-by: command-bot <>
Co-authored-by: Koute <koute@users.noreply.github.com>

substrate/primitives/keyring/src/sr25519.rs

@@ -17,14 +17,13 @@
 
 //! Support code for the runtime. A set of test accounts.
 
-use lazy_static::lazy_static;
 pub use sp_core::sr25519;
 use sp_core::{
+	hex2array,
 	sr25519::{Pair, Public, Signature},
 	ByteArray, Pair as PairT, H256,
 };
 use sp_runtime::AccountId32;
-use std::{collections::HashMap, ops::Deref};
 
 /// Set of test accounts.
 #[derive(Debug, Clone, Copy, PartialEq, Eq, Hash, strum::Display, strum::EnumIter)]
@@ -93,7 +92,7 @@ impl Keyring {
 	}
 
 	pub fn public(self) -> Public {
-		self.pair().public()
+		Public::from(self)
 	}
 
 	pub fn to_seed(self) -> String {
@@ -165,13 +164,6 @@ impl std::str::FromStr for Keyring {
 	}
 }
 
-lazy_static! {
-	static ref PRIVATE_KEYS: HashMap<Keyring, Pair> =
-		Keyring::iter().map(|i| (i, i.pair())).collect();
-	static ref PUBLIC_KEYS: HashMap<Keyring, Public> =
-		PRIVATE_KEYS.iter().map(|(&name, pair)| (name, pair.public())).collect();
-}
-
 impl From<Keyring> for AccountId32 {
 	fn from(k: Keyring) -> Self {
 		k.to_account_id()
@@ -180,7 +172,7 @@ impl From<Keyring> for AccountId32 {
 
 impl From<Keyring> for Public {
 	fn from(k: Keyring) -> Self {
-		*(*PUBLIC_KEYS).get(&k).unwrap()
+		Public::from_raw(k.into())
 	}
 }
 
@@ -192,38 +184,42 @@ impl From<Keyring> for Pair {
 
 impl From<Keyring> for [u8; 32] {
 	fn from(k: Keyring) -> Self {
-		*(*PUBLIC_KEYS).get(&k).unwrap().as_array_ref()
+		match k {
+			Keyring::Alice =>
+				hex2array!("d43593c715fdd31c61141abd04a99fd6822c8558854ccde39a5684e7a56da27d"),
+			Keyring::Bob =>
+				hex2array!("8eaf04151687736326c9fea17e25fc5287613693c912909cb226aa4794f26a48"),
+			Keyring::Charlie =>
+				hex2array!("90b5ab205c6974c9ea841be688864633dc9ca8a357843eeacf2314649965fe22"),
+			Keyring::Dave =>
+				hex2array!("306721211d5404bd9da88e0204360a1a9ab8b87c66c1bc2fcdd37f3c2222cc20"),
+			Keyring::Eve =>
+				hex2array!("e659a7a1628cdd93febc04a4e0646ea20e9f5f0ce097d9a05290d4a9e054df4e"),
+			Keyring::Ferdie =>
+				hex2array!("1cbd2d43530a44705ad088af313e18f80b53ef16b36177cd4b77b846f2a5f07c"),
+			Keyring::AliceStash =>
+				hex2array!("be5ddb1579b72e84524fc29e78609e3caf42e85aa118ebfe0b0ad404b5bdd25f"),
+			Keyring::BobStash =>
+				hex2array!("fe65717dad0447d715f660a0a58411de509b42e6efb8375f562f58a554d5860e"),
+			Keyring::CharlieStash =>
+				hex2array!("1e07379407fecc4b89eb7dbd287c2c781cfb1907a96947a3eb18e4f8e7198625"),
+			Keyring::DaveStash =>
+				hex2array!("e860f1b1c7227f7c22602f53f15af80747814dffd839719731ee3bba6edc126c"),
+			Keyring::EveStash =>
+				hex2array!("8ac59e11963af19174d0b94d5d78041c233f55d2e19324665bafdfb62925af2d"),
+			Keyring::FerdieStash =>
+				hex2array!("101191192fc877c24d725b337120fa3edc63d227bbc92705db1e2cb65f56981a"),
+			Keyring::One =>
+				hex2array!("ac859f8a216eeb1b320b4c76d118da3d7407fa523484d0a980126d3b4d0d220a"),
+			Keyring::Two =>
+				hex2array!("1254f7017f0b8347ce7ab14f96d818802e7e9e0c0d1b7c9acb3c726b080e7a03"),
+		}
 	}
 }
 
 impl From<Keyring> for H256 {
 	fn from(k: Keyring) -> Self {
-		(*PUBLIC_KEYS).get(&k).unwrap().as_array_ref().into()
-	}
-}
-
-impl From<Keyring> for &'static [u8; 32] {
-	fn from(k: Keyring) -> Self {
-		(*PUBLIC_KEYS).get(&k).unwrap().as_array_ref()
-	}
-}
-
-impl AsRef<[u8; 32]> for Keyring {
-	fn as_ref(&self) -> &[u8; 32] {
-		(*PUBLIC_KEYS).get(self).unwrap().as_array_ref()
-	}
-}
-
-impl AsRef<Public> for Keyring {
-	fn as_ref(&self) -> &Public {
-		(*PUBLIC_KEYS).get(self).unwrap()
-	}
-}
-
-impl Deref for Keyring {
-	type Target = [u8; 32];
-	fn deref(&self) -> &[u8; 32] {
-		(*PUBLIC_KEYS).get(self).unwrap().as_array_ref()
+		k.into()
 	}
 }
 
@@ -250,4 +246,8 @@ mod tests {
 			&Keyring::Bob.public(),
 		));
 	}
+	#[test]
+	fn verify_static_public_keys() {
+		assert!(Keyring::iter().all(|k| { k.pair().public().as_ref() == <[u8; 32]>::from(k) }));
+	}
 }