'use strict';
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const os = require('os');
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const hasFlag = require('has-flag');
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const env = process.env;
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const support = level => {
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if (level === 0) {
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return false;
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}
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return {
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level,
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hasBasic: true,
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has256: level >= 2,
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has16m: level >= 3
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};
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};
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let supportLevel = (() => {
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if (hasFlag('no-color') ||
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hasFlag('no-colors') ||
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hasFlag('color=false')) {
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return 0;
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}
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if (hasFlag('color=16m') ||
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hasFlag('color=full') ||
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hasFlag('color=truecolor')) {
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return 3;
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}
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if (hasFlag('color=256')) {
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return 2;
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}
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if (hasFlag('color') ||
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hasFlag('colors') ||
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hasFlag('color=true') ||
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hasFlag('color=always')) {
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return 1;
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}
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if (process.stdout && !process.stdout.isTTY) {
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return 0;
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}
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if (process.platform === 'win32') {
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// Node.js 7.5.0 is the first version of Node.js to include a patch to
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// libuv that enables 256 color output on Windows. Anything earlier and it
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// won't work. However, here we target Node.js 8 at minimum as it is an LTS
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// release, and Node.js 7 is not. Windows 10 build 10586 is the first Windows
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// release that supports 256 colors.
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const osRelease = os.release().split('.');
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if (
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Number(process.versions.node.split('.')[0]) >= 8 &&
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Number(osRelease[0]) >= 10 &&
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Number(osRelease[2]) >= 10586
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) {
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return 2;
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}
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return 1;
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}
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if ('CI' in env) {
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if (['TRAVIS', 'CIRCLECI', 'APPVEYOR', 'GITLAB_CI'].some(sign => sign in env) || env.CI_NAME === 'codeship') {
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return 1;
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}
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return 0;
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}
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if ('TEAMCITY_VERSION' in env) {
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return /^(9\.(0*[1-9]\d*)\.|\d{2,}\.)/.test(env.TEAMCITY_VERSION) ? 1 : 0;
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}
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if ('TERM_PROGRAM' in env) {
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const version = parseInt((env.TERM_PROGRAM_VERSION || '').split('.')[0], 10);
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switch (env.TERM_PROGRAM) {
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case 'iTerm.app':
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return version >= 3 ? 3 : 2;
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case 'Hyper':
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return 3;
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case 'Apple_Terminal':
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return 2;
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// No default
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}
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}
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if (/-256(color)?$/i.test(env.TERM)) {
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return 2;
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}
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if (/^screen|^xterm|^vt100|^rxvt|color|ansi|cygwin|linux/i.test(env.TERM)) {
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return 1;
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}
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if ('COLORTERM' in env) {
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return 1;
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}
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if (env.TERM === 'dumb') {
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return 0;
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}
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return 0;
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})();
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if ('FORCE_COLOR' in env) {
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supportLevel = parseInt(env.FORCE_COLOR, 10) === 0 ? 0 : (supportLevel || 1);
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}
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module.exports = process && support(supportLevel);
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