Fix 16bit func_id (paritytech#11985)

frame/contracts/src/chain_extension.rs

@@ -38,7 +38,7 @@
 //!
 //! However, only extensions implementing [`RegisteredChainExtension`] can be put into a tuple.
 //! This is because the [`RegisteredChainExtension::ID`] is used to decide which of those extensions
-//! should should be used when the contract calls a chain extensions. Extensions which are generally
+//! should be used when the contract calls a chain extensions. Extensions which are generally
 //! useful should claim their `ID` with [the registry](https://github.com/paritytech/chainextension-registry)
 //! so that no collisions with other vendors will occur.
 //!
@@ -215,7 +215,7 @@ where
  /// It returns the two least significant bytes of the `id` passed by a contract as the other
  /// two bytes represent the chain extension itself (the code which is calling this function).
  pub fn func_id(&self) -> u16 {
- (self.inner.id & 0x00FF) as u16
+ (self.inner.id & 0x0000FFFF) as u16
  }
 
  /// The chain extension id within the `id` passed by a contract.

frame/contracts/src/tests.rs

@@ -158,28 +158,28 @@ impl ChainExtension<Test> for TestExtension {
  let func_id = env.func_id();
  let id = env.ext_id() as u32 | func_id as u32;
  match func_id {
- 0 => {
+ 0x8000 => {
  let mut env = env.buf_in_buf_out();
  let input = env.read(8)?;
  env.write(&input, false, None)?;
  TEST_EXTENSION.with(|e| e.borrow_mut().last_seen_buffer = input);
  Ok(RetVal::Converging(id))
  },
- 1 => {
+ 0x8001 => {
  let env = env.only_in();
  TEST_EXTENSION.with(|e| {
  e.borrow_mut().last_seen_inputs =
  (env.val0(), env.val1(), env.val2(), env.val3())
  });
  Ok(RetVal::Converging(id))
  },
- 2 => {
+ 0x8002 => {
  let mut env = env.buf_in_buf_out();
  let weight = env.read(5)?[4].into();
  env.charge_weight(weight)?;
  Ok(RetVal::Converging(id))
  },
- 3 => Ok(RetVal::Diverging { flags: ReturnFlags::REVERT, data: vec![42, 99] }),
+ 0x8003 => Ok(RetVal::Diverging { flags: ReturnFlags::REVERT, data: vec![42, 99] }),
  _ => {
  panic!("Passed unknown id to test chain extension: {}", func_id);
  },
@@ -1646,36 +1646,37 @@ fn chain_extension_works() {
  ),);
  let addr = Contracts::contract_address(&ALICE, &hash, &[]);
 
- // 0 = read input buffer and pass it through as output
- let input: Vec<u8> = ExtensionInput { extension_id: 0, func_id: 0, extra: &[99] }.into();
+ // 0x8000 = read input buffer and pass it through as output
+ let input: Vec<u8> =
+ ExtensionInput { extension_id: 0, func_id: 0x8000, extra: &[99] }.into();
  let result =
  Contracts::bare_call(ALICE, addr.clone(), 0, GAS_LIMIT, None, input.clone(), false);
  assert_eq!(TestExtension::last_seen_buffer(), input);
  assert_eq!(result.result.unwrap().data, Bytes(input));
 
- // 1 = treat inputs as integer primitives and store the supplied integers
+ // 0x8001 = treat inputs as integer primitives and store the supplied integers
  Contracts::bare_call(
  ALICE,
  addr.clone(),
  0,
  GAS_LIMIT,
  None,
- ExtensionInput { extension_id: 0, func_id: 1, extra: &[] }.into(),
+ ExtensionInput { extension_id: 0, func_id: 0x8001, extra: &[] }.into(),
  false,
  )
  .result
  .unwrap();
  // those values passed in the fixture
  assert_eq!(TestExtension::last_seen_inputs(), (4, 4, 16, 12));
 
- // 2 = charge some extra weight (amount supplied in the fifth byte)
+ // 0x8002 = charge some extra weight (amount supplied in the fifth byte)
  let result = Contracts::bare_call(
  ALICE,
  addr.clone(),
  0,
  GAS_LIMIT,
  None,
- ExtensionInput { extension_id: 0, func_id: 2, extra: &[0] }.into(),
+ ExtensionInput { extension_id: 0, func_id: 0x8002, extra: &[0] }.into(),
  false,
  );
  assert_ok!(result.result);
@@ -1686,7 +1687,7 @@ fn chain_extension_works() {
  0,
  GAS_LIMIT,
  None,
- ExtensionInput { extension_id: 0, func_id: 2, extra: &[42] }.into(),
+ ExtensionInput { extension_id: 0, func_id: 0x8002, extra: &[42] }.into(),
  false,
  );
  assert_ok!(result.result);
@@ -1697,20 +1698,20 @@ fn chain_extension_works() {
  0,
  GAS_LIMIT,
  None,
- ExtensionInput { extension_id: 0, func_id: 2, extra: &[95] }.into(),
+ ExtensionInput { extension_id: 0, func_id: 0x8002, extra: &[95] }.into(),
  false,
  );
  assert_ok!(result.result);
  assert_eq!(result.gas_consumed, gas_consumed + 95);
 
- // 3 = diverging chain extension call that sets flags to 0x1 and returns a fixed buffer
+ // 0x8003 = diverging chain extension call that sets flags to 0x1 and returns a fixed buffer
  let result = Contracts::bare_call(
  ALICE,
  addr.clone(),
  0,
  GAS_LIMIT,
  None,
- ExtensionInput { extension_id: 0, func_id: 3, extra: &[] }.into(),
+ ExtensionInput { extension_id: 0, func_id: 0x8003, extra: &[] }.into(),
  false,
  )
  .result