转载自：
Maple13 的 blog 的文章ERESOLVE unable to resolve dependency tree

报错现象

npm ERR! code ERESOLVE
npm ERR! ERESOLVE unable to resolve dependency tree
npm ERR!
npm ERR! While resolving: ant-design-pro@4.1.0
npm ERR! Found: react@16.14.0
npm ERR! node_modules/react
npm ERR!   react@"^16.8.6" from the root project
npm ERR!
npm ERR! Could not resolve dependency:
npm ERR! peer react@"^15.0.0" from react-fittext@1.0.0
npm ERR! node_modules/react-fittext
npm ERR!   react-fittext@"^1.0.0" from the root project
npm ERR!
npm ERR! Fix the upstream dependency conflict, or retry
npm ERR! this command with --force, or --legacy-peer-deps
npm ERR! to accept an incorrect (and potentially broken) dependency resolution.
npm ERR!
npm ERR! See C:\Users\issuser\AppData\Local\npm-cache\eresolve-report.txt for a full report.

npm ERR! A complete log of this run can be found in:
npm ERR!     C:\Users\issuser\AppData\Local\npm-cache\_logs\2021-06-10T07_34_08_028Z-debug.log

出现原因

升级 npm 至 v7.6.2 后, 运行 npm i 安装依赖，报错 ERESOLVE unable to resolve dependency tree

环境

• node: 16.3.0
• npm: 7.6.2
• React项目

错误原因

等依赖项中存在无法解决的冲突，npm@7 现在尝试安装它们，而npm@6没有。

解决方案

使用 npm i --legacy-peer-deps

参考

[BUG] ERESOLVE无法解析依赖关系树（postcss-load-config，svelte-preprocess）
npm 7 is now generally available!