cross-env
Version:
Run scripts that set and use environment variables across platforms
58 lines (57 loc) • 2.46 kB
JavaScript
import { isWindows } from "./is-windows.js";
const pathLikeEnvVarWhitelist = new Set(['PATH', 'NODE_PATH']);
/**
* This will transform UNIX-style list values to Windows-style.
* For example, the value of the $PATH variable "/usr/bin:/usr/local/bin:."
* will become "/usr/bin;/usr/local/bin;." on Windows.
* @param varValue Original value of the env variable
* @param varName Original name of the env variable
* @returns Converted value
*/
function replaceListDelimiters(varValue, varName = '') {
const targetSeparator = isWindows() ? ';' : ':';
if (!pathLikeEnvVarWhitelist.has(varName)) {
return varValue;
}
return varValue.replace(/(\\*):/g, (match, backslashes) => {
if (backslashes.length % 2) {
// Odd number of backslashes preceding it means it's escaped,
// remove 1 backslash and return the rest as-is
return match.substring(1);
}
return backslashes + targetSeparator;
});
}
/**
* This will attempt to resolve the value of any env variables that are inside
* this string. For example, it will transform this:
* cross-env FOO=$NODE_ENV BAR=\\$NODE_ENV echo $FOO $BAR
* Into this:
* FOO=development BAR=$NODE_ENV echo $FOO
* (Or whatever value the variable NODE_ENV has)
* Note that this function is only called with the right-side portion of the
* env var assignment, so in that example, this function would transform
* the string "$NODE_ENV" into "development"
* @param varValue Original value of the env variable
* @returns Converted value
*/
function resolveEnvVars(varValue) {
const envUnixRegex = /(\\*)(\$(\w+)|\${(\w+)})/g; // $my_var or ${my_var} or \$my_var
return varValue.replace(envUnixRegex, (_, escapeChars, varNameWithDollarSign, varName, altVarName) => {
// do not replace things preceded by a odd number of \
if (escapeChars.length % 2 === 1) {
return varNameWithDollarSign;
}
return (escapeChars.substring(0, escapeChars.length / 2) +
(process.env[varName || altVarName] || ''));
});
}
/**
* Converts an environment variable value to be appropriate for the current OS.
* @param originalValue Original value of the env variable
* @param originalName Original name of the env variable
* @returns Converted value
*/
export function varValueConvert(originalValue, originalName) {
return resolveEnvVars(replaceListDelimiters(originalValue, originalName));
}