node/test/parallel/test-repl-envvars.js

'use strict';

// Flags: --expose-internals

require('../common');
const stream = require('stream');
const { describe, test } = require('node:test');
const REPL = require('internal/repl');
const assert = require('assert');
const inspect = require('util').inspect;
const { REPL_MODE_SLOPPY, REPL_MODE_STRICT } = require('repl');

const tests = [
  {
    env: {},
    expected: { terminal: true, useColors: false }
  },
  {
    env: { NODE_DISABLE_COLORS: '1' },
    expected: { terminal: true, useColors: false }
  },
  {
    env: { NODE_DISABLE_COLORS: '1', FORCE_COLOR: '1' },
    expected: { terminal: true, useColors: true }
  },
  {
    env: { NODE_NO_READLINE: '1' },
    expected: { terminal: false, useColors: false }
  },
  {
    env: { TERM: 'dumb' },
    expected: { terminal: true, useColors: false }
  },
  {
    env: { TERM: 'dumb', FORCE_COLOR: '1' },
    expected: { terminal: true, useColors: true }
  },
  {
    env: { NODE_NO_READLINE: '1', NODE_DISABLE_COLORS: '1' },
    expected: { terminal: false, useColors: false }
  },
  {
    env: { NODE_NO_READLINE: '0' },
    expected: { terminal: true, useColors: false }
  },
  {
    env: { NODE_REPL_MODE: 'sloppy' },
    expected: { terminal: true, useColors: false, replMode: REPL_MODE_SLOPPY }
  },
  {
    env: { NODE_REPL_MODE: 'strict' },
    expected: { terminal: true, useColors: false, replMode: REPL_MODE_STRICT }
  },
];

function run(test) {
  const env = test.env;
  const expected = test.expected;

  const opts = {
    terminal: true,
    input: new stream.Readable({ read() {} }),
    output: new stream.Writable({ write() {} })
  };

  Object.assign(process.env, env);

  return new Promise((resolve) => {
    REPL.createInternalRepl(process.env, opts, function(err, repl) {
      assert.ifError(err);

      assert.strictEqual(repl.terminal, expected.terminal,
                         `Expected ${inspect(expected)} with ${inspect(env)}`);
      assert.strictEqual(repl.useColors, expected.useColors,
                         `Expected ${inspect(expected)} with ${inspect(env)}`);
      assert.strictEqual(repl.replMode, expected.replMode || REPL_MODE_SLOPPY,
                         `Expected ${inspect(expected)} with ${inspect(env)}`);
      for (const key of Object.keys(env)) {
        delete process.env[key];
      }
      repl.close();
      resolve();
    });
  });
}

describe('REPL environment variables', { concurrency: 1 }, () => {
  tests.forEach((testCase) => test(inspect(testCase.env), () => run(testCase)));
});