export function parseError()

in ui/src/parseError.ts [13:91]
55 lines of code
21 McCabe index (conditional complexity)

export function parseError(error: any): IParsedError {
    let errorType: string = '';
    let message: string = '';
    let stack: string | undefined;
    let stepName: string | undefined;

    if (typeof (error) === 'object' && error !== null) {
        if (error.constructor !== Object) {
            errorType = error.constructor.name;
        }

        stack = getCallstack(error);
        errorType = getCode(error, errorType);

        // See https://github.com/Microsoft/vscode-azureappservice/issues/419 for an example error that requires these 'unpack's
        error = unpackErrorFromField(error, 'value');
        error = unpackErrorFromField(error, '_value');
        error = unpackErrorFromField(error, 'error');
        error = unpackErrorFromField(error, 'error');
        if (Array.isArray(error.errors) && error.errors.length) {
            error = error.errors[0];
        }

        errorType = getCode(error, errorType);
        message = getMessage(error, message);

        if (!errorType || !message || /error.*deserializing.*response.*body/i.test(message)) {
            error = unpackErrorFromField(error, 'response');
            error = unpackErrorFromField(error, 'body');

            errorType = getCode(error, errorType);
            message = getMessage(error, message);
        }

        // Azure errors have a JSON object in the message
        let parsedMessage: any = parseIfJson(error.message);
        // For some reason, the message is sometimes serialized twice and we need to parse it again
        parsedMessage = parseIfJson(parsedMessage);
        // Extract out the "internal" error if it exists
        if (parsedMessage && parsedMessage.error) {
            parsedMessage = parsedMessage.error;
        }

        errorType = getCode(parsedMessage, errorType);
        message = getMessage(parsedMessage, message);

        message ||= convertCodeToError(errorType) || JSON.stringify(error);

        if ('stepName' in error && typeof error.stepName === 'string') {
            stepName = error.stepName;
        }
    } else if (error !== undefined && error !== null && error.toString && error.toString().trim() !== '') {
        errorType = typeof (error);
        message = error.toString();
    }

    message = unpackErrorsInMessage(message);

    [message, errorType] = parseIfFileSystemError(message, errorType);

    errorType ||= typeof (error);
    message ||= localize('unknownError', 'Unknown Error');

    message = parseIfHtml(message);

    // Azure storage SDK errors are presented in XML
    // https://github.com/Azure/azure-sdk-for-js/issues/6927
    message = parseIfXml(message);

    return {
        errorType: errorType,
        message: message,
        stack: stack,
        stepName,
        // NOTE: Intentionally not using 'error instanceof UserCancelledError' because that doesn't work if multiple versions of the UI package are used in one extension
        // See https://github.com/Microsoft/vscode-azuretools/issues/51 for more info
        isUserCancelledError: errorType === 'UserCancelledError'
    };
}