test: refactor EnumCoder tests (#938)

* test: refactor and increase verbosity of enum coder tests

* chore: changeset

* test: introduce test cases for native enums

* test: add feature test in abi coder for native enum

* test: remove abi coder test case for native enum as redundant

---------

Co-authored-by: danielbate <--global>

.changeset/gold-swans-hear.md

@@ -0,0 +1,2 @@
+---
+---

packages/abi-coder/src/abi-coder.test.ts

@@ -3,6 +3,7 @@ import { bn, toHex } from '@fuel-ts/math';
 
 import AbiCoder from './abi-coder';
 import type { DecodedValue } from './coders/abstract-coder';
+import type { JsonAbiFragmentType } from './json-abi';
 
 const B256 = '0xd5579c46dfcc7f18207013e65b44e4cb4e2c2298f4ac457ba8f82743f31e930b';
 

packages/abi-coder/src/coders/enum.test.ts

@@ -0,0 +1,109 @@
+/* eslint-disable @typescript-eslint/ban-ts-comment */
+import { bn } from '@fuel-ts/math';
+import { executionAsyncId } from 'async_hooks';
+
+import { U64_MAX } from '../../test/utils/constants';
+
+import type Coder from './abstract-coder';
+import ArrayCoder from './array';
+import BooleanCoder from './boolean';
+import EnumCoder from './enum';
+import NumberCoder from './number';
+import U64Coder from './u64';
+
+describe('EnumCoder', () => {
+  const coder = new EnumCoder('TestEnum', { a: new BooleanCoder(), b: new U64Coder() });
+
+  it('should encode an enum containing a boolean', () => {
+    const expected = new Uint8Array([0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 1]);
+    const actual = coder.encode({ a: true });
+
+    expect(actual).toStrictEqual(expected);
+  });
+
+  it('should decode an enum containing a boolean', () => {
+    const expectedValue = { a: true };
+    const expectedLength = 16;
+    const [actualValue, actualLength] = coder.decode(
+      new Uint8Array([0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 1]),
+      0
+    );
+
+    expect(actualValue).toStrictEqual(expectedValue);
+    expect(actualLength).toBe(expectedLength);
+  });
+
+  it('should encode an enum containing a u64', () => {
+    const expected = new Uint8Array([
+      0, 0, 0, 0, 0, 0, 0, 1, 255, 255, 255, 255, 255, 255, 255, 255,
+    ]);
+    const actual = coder.encode({ b: bn(U64_MAX) });
+
+    expect(actual).toStrictEqual(expected);
+  });
+
+  it('should decode an enum containing a u64', () => {
+    const expectedValue = { b: bn(U64_MAX) };
+    const expectedLength = 16;
+    const [actualValue, actualLength] = coder.decode(
+      new Uint8Array([0, 0, 0, 0, 0, 0, 0, 1, 255, 255, 255, 255, 255, 255, 255, 255]),
+      0
+    );
+
+    expect(actualValue).toStrictEqual(expectedValue);
+    expect(actualLength).toBe(expectedLength);
+  });
+
+  it('should throw an error when encoding if no enum key is provided', () => {
+    const invalidCoder = new EnumCoder('TestEnum', {});
+
+    expect(() => invalidCoder.encode({} as never)).toThrow('A field for the case must be provided');
+  });
+
+  it.skip('should encode a native enum', () => {
+    // TODO: complete encode native enum test case
+  });
+
+  it.skip('should decode a native enum', () => {
+    // TODO: complete decode native enum test case
+  });
+
+  it('should throw an error when decoded value accesses an invalid index', () => {
+    const input = new Uint8Array(Array.from(Array(3).keys()));
+    expect(() => {
+      coder.decode(input, 1);
+    }).toThrow('Invalid caseIndex');
+  });
+
+  it('should not throw given correctly typed inputs', () => {
+    expect(() => coder.encode({ a: true })).not.toThrow();
+    expect(() => coder.encode({ b: bn(1234) })).not.toThrow();
+  });
+
+  it('should throw when provided with extra inputs', () => {
+    expect(() =>
+      coder.encode(
+        // @ts-expect-error
+        { a: true, b: bn(1234), c: false }
+      )
+    ).toThrow('Only one field must be provided');
+  });
+
+  it('should throw type error with invalid input for coder', () => {
+    expect(() =>
+      coder.encode(
+        // @ts-expect-error
+        { b: true }
+      )
+    ).toThrow('Invalid u64');
+  });
+
+  it('should throw type error with invalid input key', () => {
+    expect(() =>
+      coder.encode(
+        // @ts-expect-error
+        { nope: 42 }
+      )
+    ).toThrow();
+  });
+});