/**
 * For server-side CSS imports, we need to ignore the actual module content but
 * still trigger the hot-reloading diff mechanism. So here we put the content
 * inside a comment.
 */ import crypto from 'crypto';
const NextServerCSSLoader = function(content) {
    this.cacheable && this.cacheable();
    const options = this.getOptions();
    let isCSSModule = options.cssModules;
    // Only add the checksum during development.
    if (process.env.NODE_ENV !== 'production') {
        // This check is only for backwards compatibility.
        // TODO: Remove this in the next major version (next 14)
        if (isCSSModule === undefined) {
            this.emitWarning(Object.defineProperty(new Error("No 'cssModules' option was found for the next-flight-css-loader plugin."), "__NEXT_ERROR_CODE", {
                value: "E8",
                enumerable: false
            }));
            isCSSModule = this.resourcePath.match(/\.module\.(css|sass|scss)$/) !== null;
        }
        const checksum = crypto.createHash('sha1').update(typeof content === 'string' ? Buffer.from(content) : content).digest().toString('hex').substring(0, 12);
        if (isCSSModule) {
            return `\
${content}
module.exports.__checksum = ${JSON.stringify(checksum)}
`;
        }
        // Server CSS imports are always available for HMR, so we attach
        // `module.hot.accept()` to the generated module.
        const hmrCode = 'if (module.hot) { module.hot.accept() }';
        return `\
export default ${JSON.stringify(checksum)}
${hmrCode}
`;
    }
    return content;
};
export default NextServerCSSLoader;

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