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error An unexpected error occurred: "G:\\yarnConfig\\yarn_cache\\v6\\npm-serialize-javascript-5.0.1-7886ec848049a462467a97d3d918ebb2aaf934f4-integrity\\node_modules\\serialize-javascript\\.yarn-metadata.json: Unexpected end of JSON input".
info If you think this is a bug, please open a bug report with the information provided in "H:\\react\\react\\code\\code\\yarn-error.log".
info Visit https://yarnpkg.com/en/docs/cli/add for documentation about this command.
试试切换淘宝源或者，cnpm，npm切换淘宝源 或者npx切换淘宝源 https://segmentfault.com/q/1010000021786171/a-1020000021787532