Function resolveVariables

Extension/src/common.ts:383–460

(input: string | undefined, additionalEnvironment?: Record<string, string | string[]>, arrayResults?: string[])

// Pass in 'arrayResults' if a string[] result is possible and a delimited string result is undesirable.
// The string[] result will be copied into 'arrayResults'.
export function resolveVariables(input: string | undefined, additionalEnvironment?: Record<string, string | string[]>, arrayResults?: string[]): string {
    if (!input) {
        return "";
    }

    // jsonc parser may assign a non-string object to a string.
    // TODO: https://github.com/microsoft/vscode-cpptools/issues/9414
    if (!isString(input)) {
        const inputAny: any = input;
        input = inputAny.toString();
        return input ?? "";
    }

    // Replace environment and configuration variables.
    const regexp: () => RegExp = () => /\$\{((env|config|workspaceFolder)(\.|:))?(.*?)\}/g;
    let ret: string = input;
    const cycleCache = new Set<string>();
    while (!cycleCache.has(ret)) {
        cycleCache.add(ret);
        ret = ret.replace(regexp(), (match: string, ignored1: string | undefined, varType: string | undefined, ignored2: string | undefined, name: string) => {
            let newValue: string | undefined;
            switch (varType) {
                // Historically, if the variable didn't have anything before the "." or ":"
                // it was assumed to be an environment variable
                case undefined:
                case "env": {
                    if (additionalEnvironment) {
                        const v: string | string[] | undefined = additionalEnvironment[name];
                        if (isString(v)) {
                            newValue = v;
                        } else if (input === match && isArrayOfString(v)) {
                            if (arrayResults !== undefined) {
                                arrayResults.push(...v);
                                newValue = "";
                                break;
                            } else {
                                newValue = v.join(path.delimiter);
                            }
                        }
                    }
                    if (newValue === undefined) {
                        newValue = process.env[name];
                    }

                    // If the environment variable is not set, we return an empty string. Only do
                    // this for ${env:X} variables, not ${X} variables.
                    if (newValue === undefined && varType !== undefined) {
                        newValue = "";
                    }
                    break;
                }
                case "config": {
                    const config: vscode.WorkspaceConfiguration = vscode.workspace.getConfiguration();
                    if (config) {
                        newValue = config.get<string>(name);
                    }
                    break;
                }