♻️ refactor(config.ts): Addition of UnitTest environment and unittest for commands/config.ts#getConfig (#330)

* feat(jest.config.ts): update jest preset for TS ESM support and ignore patterns
feat(package.json): add test:unit script with NODE_OPTIONS for ESM
refactor(src/commands/config.ts): improve dotenv usage with dynamic paths
feat(src/commands/config.ts): allow custom config and env paths in getConfig
refactor(src/commands/config.ts): streamline environment variable access

feat(test/unit): add unit tests for config handling and utility functions

- Implement unit tests for `getConfig` function to ensure correct behavior
  in various scenarios including default values, global config, and local
  env file precedence.
- Add utility function `prepareFile` for creating temporary files during
  tests, facilitating testing of file-based configurations.

* feat(e2e.yml): add unit-test job to GitHub Actions for running unit tests on pull requests

* ci(test.yml): add GitHub Actions workflow for unit and e2e tests on pull requests

* refactor(config.ts): streamline environment variable access using process.env directly
test(config.test.ts): add setup and teardown for environment variables in tests to ensure test isolation

* feat(package.json): add `test:all` script to run all tests in Docker
refactor(package.json): consolidate Docker build steps into `test:docker-build` script for DRY principle
fix(package.json): ensure `test:unit:docker` and `test:e2e:docker` scripts use the same Docker image and remove container after run
chore(test/Dockerfile): remove default CMD to allow dynamic test script execution in Docker

* refactor(config.test.ts): anonymize API keys in tests for better security practices

* feat(config.test.ts): add tests for OCO_ANTHROPIC_API_KEY configuration

* refactor(config.ts): streamline path imports and remove unused DotenvParseOutput

- Simplify path module imports by removing default import and using named imports for `pathJoin` and `pathResolve`.
- Remove unused `DotenvParseOutput` import to clean up the code.

* refactor(config.test.ts): simplify API key mock values for clarity in tests

* test(config.test.ts): remove tests for default config values and redundant cases

- Removed tests that checked for default config values when no config or env files are present, as these scenarios are now handled differently.
- Eliminated tests for empty global config and local env files to streamline testing focus on actual config loading logic.
- Removed test for prioritizing local env over global config due to changes in config loading strategy, simplifying the configuration management.

src/commands/config.ts

@@ -4,15 +4,13 @@ import * as dotenv from 'dotenv';
 import { existsSync, readFileSync, writeFileSync } from 'fs';
 import { parse as iniParse, stringify as iniStringify } from 'ini';
 import { homedir } from 'os';
-import { join as pathJoin } from 'path';
+import { join as pathJoin, resolve as pathResolve } from 'path';
 
 import { intro, outro } from '@clack/prompts';
 
 import { COMMANDS } from '../CommandsEnum';
 import { getI18nLocal } from '../i18n';
 
-dotenv.config();
-
 export enum CONFIG_KEYS {
   OCO_OPENAI_API_KEY = 'OCO_OPENAI_API_KEY',
   OCO_ANTHROPIC_API_KEY = 'OCO_ANTHROPIC_API_KEY',
@@ -248,9 +246,17 @@ export type ConfigType = {
   [key in CONFIG_KEYS]?: any;
 };
 
-const configPath = pathJoin(homedir(), '.opencommit');
+const defaultConfigPath = pathJoin(homedir(), '.opencommit');
+const defaultEnvPath = pathResolve(process.cwd(), '.env');
 
-export const getConfig = (): ConfigType | null => {
+export const getConfig = ({
+  configPath = defaultConfigPath,
+  envPath = defaultEnvPath
+}: {
+  configPath?: string
+  envPath?: string
+} = {}): ConfigType | null => {
+  dotenv.config({ path: envPath });
   const configFromEnv = {
     OCO_OPENAI_API_KEY: process.env.OCO_OPENAI_API_KEY,
     OCO_ANTHROPIC_API_KEY: process.env.OCO_ANTHROPIC_API_KEY,
@@ -306,7 +312,7 @@ export const getConfig = (): ConfigType | null => {
   return config;
 };
 
-export const setConfig = (keyValues: [key: string, value: string][]) => {
+export const setConfig = (keyValues: [key: string, value: string][], configPath: string = defaultConfigPath) => {
   const config = getConfig() || {};
 
   for (const [configKey, configValue] of keyValues) {