feat(keyring-utils): add isScopeEqual + isScopeEqualToAny

packages/keyring-utils/src/scopes.test.ts

@@ -0,0 +1,58 @@
+import { isScopeEqual, isScopeEqualToAny } from './scopes';
+
+const ETH_EOA = 'eip155:0';
+const ETH_MAINNET = 'eip155:1';
+const ETH_TESTNET = 'eip155:11155111';
+const BTC_MAINNET = 'bip122:000000000019d6689c085ae165831e93';
+const BTC_TESTNET = 'bip122:000000000933ea01ad0ee984209779ba';
+
+describe('isScopeEqual', () => {
+  it('returns true when both scopes are equal', () => {
+    expect(isScopeEqual(ETH_MAINNET, ETH_MAINNET)).toBe(true);
+    expect(isScopeEqual(ETH_TESTNET, ETH_TESTNET)).toBe(true);
+    expect(isScopeEqual(BTC_MAINNET, BTC_MAINNET)).toBe(true);
+    expect(isScopeEqual(BTC_TESTNET, BTC_TESTNET)).toBe(true);
+  });
+
+  it('returns false when both scopes are not equal', () => {
+    expect(isScopeEqual(ETH_MAINNET, ETH_TESTNET)).toBe(false);
+    expect(isScopeEqual(ETH_TESTNET, ETH_MAINNET)).toBe(false);
+    expect(isScopeEqual(BTC_MAINNET, BTC_TESTNET)).toBe(false);
+    expect(isScopeEqual(BTC_TESTNET, BTC_MAINNET)).toBe(false);
+  });
+
+  it('supports EVM EOA scopes', () => {
+    expect(isScopeEqual(ETH_MAINNET, ETH_EOA)).toBe(true);
+    expect(isScopeEqual(ETH_TESTNET, ETH_EOA)).toBe(true);
+    expect(isScopeEqual(ETH_EOA, ETH_MAINNET)).toBe(true);
+    expect(isScopeEqual(ETH_EOA, ETH_TESTNET)).toBe(true);
+
+    expect(isScopeEqual(ETH_EOA, BTC_MAINNET)).toBe(false);
+    expect(isScopeEqual(BTC_MAINNET, ETH_EOA)).toBe(false);
+  });
+});
+
+describe('isScopeEqualToAny', () => {
+  it('returns true when both scopes are equal', () => {
+    expect(isScopeEqualToAny(ETH_MAINNET, [ETH_TESTNET, ETH_MAINNET])).toBe(
+      true,
+    );
+    expect(isScopeEqualToAny(BTC_MAINNET, [BTC_MAINNET, BTC_TESTNET])).toBe(
+      true,
+    );
+  });
+
+  it('returns false when both scopes are not equal', () => {
+    expect(isScopeEqualToAny(ETH_MAINNET, [ETH_TESTNET])).toBe(false);
+    expect(isScopeEqualToAny(ETH_MAINNET, [])).toBe(false);
+    expect(isScopeEqualToAny(BTC_MAINNET, [ETH_MAINNET])).toBe(false);
+  });
+
+  it('supports EVM EOA scopes', () => {
+    expect(isScopeEqualToAny(ETH_EOA, [ETH_TESTNET, ETH_MAINNET])).toBe(true);
+    expect(isScopeEqualToAny(ETH_MAINNET, [ETH_TESTNET, ETH_EOA])).toBe(true);
+
+    expect(isScopeEqualToAny(BTC_MAINNET, [ETH_TESTNET, ETH_EOA])).toBe(false);
+    expect(isScopeEqualToAny(ETH_EOA, [BTC_MAINNET, BTC_TESTNET])).toBe(false);
+  });
+});

packages/keyring-utils/src/scopes.ts

@@ -0,0 +1,50 @@
+import type { CaipChainId } from '@metamask/utils';
+import { KnownCaipNamespace } from '@metamask/utils';
+
+// We do not uses the `EthScope` from `@metamask/keyring-api` here, to avoid pulling it
+// as a dependency.
+export const ETH_SCOPE_EOA = `${KnownCaipNamespace.Eip155}:0`;
+
+// We use a string prefix when comparing EOAs to avoid unecessary splits.
+const ETH_SCOPE_PREFIX = `${KnownCaipNamespace.Eip155}:`;
+
+/**
+ * Check if scope is compatible with a list of scopes. It also supports the special
+ * case of `eip155:0` for EVM EOA chain ID which is compatible with any EVM chain
+ * ID (`eip155:*`).
+ *
+ * @param scope - The scope (CAIP-2 chain ID) to check.
+ * @param other - Another scope to compare to.
+ * @returns True if both scope are compatible, false otherwise.
+ */
+export function isScopeEqual(scope: CaipChainId, other: CaipChainId): boolean {
+  const isScopeEoa = scope === ETH_SCOPE_EOA;
+  const isOtherEoa = other === ETH_SCOPE_EOA;
+
+  // Special case for EOA scopes (we check on both sides);
+  if (isScopeEoa) {
+    return other.startsWith(ETH_SCOPE_PREFIX);
+  }
+  if (isOtherEoa) {
+    return scope.startsWith(ETH_SCOPE_PREFIX);
+  }
+
+  // Normal case, if both scope stricly matches, then they are compatible.
+  return scope === other;
+}
+
+/**
+ * Check if scope is compatible with a list of scopes. It also supports the special
+ * case of `eip155:0` for EVM EOA chain ID which is compatible with any EVM chain
+ * ID (`eip155:*`).
+ *
+ * @param scope - The scope (CAIP-2 chain ID) to check.
+ * @param scopes - The list of scopes to check against.
+ * @returns True if the scope is compatible within the list of scopes.
+ */
+export function isScopeEqualToAny(
+  scope: CaipChainId,
+  scopes: CaipChainId[],
+): boolean {
+  return scopes.some((other) => isScopeEqual(scope, other));
+}