删除.browserslistrc文件就好了

$ npm run dev

> bootstrap-vue@1.0.0 dev E:\aawork\1work\2019.2\bootstrap-vue
> webpack-dev-server --inline --progress --config build/webpack.dev.conf.js

13% building modules 33/37 modules 4 active ...rap-vue\src\components\HelloWorld.vue{ parser: "b 15% building modules 42/45 modules 3 active ...9.2\bootstrap-vue\src\assets\logo.png{ BrowserslistError: E:\aawork\1work\2019.2\bootstrap-vue contains both .browserslistrc and package.json with browsers
at E:\aawork\1work\2019.2\bootstrap-vue\node_modules\_browserslist@2.11.3@browserslist\node.js:192:15
at eachParent (E:\aawork\1work\2019.2\bootstrap-vue\node_modules\_browserslist@2.11.3@browserslist\node.js:43:18)
at Object.findConfig (E:\aawork\1work\2019.2\bootstrap-vue\node_modules\_browserslist@2.11.3@browserslist\node.js:172:20)
at Object.loadConfig (E:\aawork\1work\2019.2\bootstrap-vue\node_modules\_browserslist@2.11.3@browserslist\node.js:126:37)
at browserslist (E:\aawork\1work\2019.2\bootstrap-vue\node_modules\_browserslist@2.11.3@browserslist\index.js:194:22)
at Browsers.parse (E:\aawork\1work\2019.2\bootstrap-vue\node_modules\_autoprefixer@7.2.6@autoprefixer\lib\browsers.js:61:16)
at new Browsers (E:\aawork\1work\2019.2\bootstrap-vue\node_modules\_autoprefixer@7.2.6@autoprefixer\lib\browsers.js:52:30)
at loadPrefixes (E:\aawork\1work\2019.2\bootstrap-vue\node_modules\_autoprefixer@7.2.6@autoprefixer\lib\autoprefixer.js:70:24)
at plugin (E:\aawork\1work\2019.2\bootstrap-vue\node_modules\_autoprefixer@7.2.6@autoprefixer\lib\autoprefixer.js:81:24)
at LazyResult.run (E:\aawork\1work\2019.2\bootstrap-vue\node_modules\_postcss@6.0.23@postcss\lib\lazy-result.js:277:20)
at LazyResult.asyncTick (E:\aawork\1work\2019.2\bootstrap-vue\node_modules\_postcss@6.0.23@postcss\lib\lazy-result.js:192:32)
at LazyResult.asyncTick (E:\aawork\1work\2019.2\bootstrap-vue\node_modules\_postcss@6.0.23@postcss\lib\lazy-result.js:204:22)
at E:\aawork\1work\2019.2\bootstrap-vue\node_modules\_postcss@6.0.23@postcss\lib\lazy-result.js:197:27
at <anonymous>
name: 'BrowserslistError',
message: 'E:\\aawork\\1work\\2019.2\\bootstrap-vue contains both .browserslistrc and package.json with browsers',
browserslist: true } 15% building modules 43/45 modules 2 active ...9.2\bootstrap-vue\src\assets\logo.png{ BrowserslistError: E:\aawork\1work\2019.2\bootstrap-vue contains both .browserslistrc and package.json with browsers
at E:\aawork\1work\2019.2\bootstrap-vue\node_modules\_browserslist@2.11.3@browserslist\node.js:192:15
at eachParent (E:\aawork\1work\2019.2\bootstrap-vue\node_modules\_browserslist@2.11.3@browserslist\node.js:43:18)
at Object.findConfig (E:\aawork\1work\2019.2\bootstrap-vue\node_modules\_browserslist@2.11.3@browserslist\node.js:172:20)
at Object.loadConfig (E:\aawork\1work\2019.2\bootstrap-vue\node_modules\_browserslist@2.11.3@browserslist\node.js:126:37)
at browserslist (E:\aawork\1work\2019.2\bootstrap-vue\node_modules\_browserslist@2.11.3@browserslist\index.js:194:22)
at Browsers.parse (E:\aawork\1work\2019.2\bootstrap-vue\node_modules\_autoprefixer@7.2.6@autoprefixer\lib\browsers.js:61:16)
at new Browsers (E:\aawork\1work\2019.2\bootstrap-vue\node_modules\_autoprefixer@7.2.6@autoprefixer\lib\browsers.js:52:30)
at loadPrefixes (E:\aawork\1work\2019.2\bootstrap-vue\node_modules\_autoprefixer@7.2.6@autoprefixer\lib\autoprefixer.js:70:24)
at plugin (E:\aawork\1work\2019.2\bootstrap-vue\node_modules\_autoprefixer@7.2.6@autoprefixer\lib\autoprefixer.js:81:24)
at LazyResult.run (E:\aawork\1work\2019.2\bootstrap-vue\node_modules\_postcss@6.0.23@postcss\lib\lazy-result.js:277:20)
at LazyResult.asyncTick (E:\aawork\1work\2019.2\bootstrap-vue\node_modules\_postcss@6.0.23@postcss\lib\lazy-result.js:192:32)
at LazyResult.asyncTick (E:\aawork\1work\2019.2\bootstrap-vue\node_modules\_postcss@6.0.23@postcss\lib\lazy-result.js:204:22)
at E:\aawork\1work\2019.2\bootstrap-vue\node_modules\_postcss@6.0.23@postcss\lib\lazy-result.js:197:27
at <anonymous>
name: 'BrowserslistError',
message: 'E:\\aawork\\1work\\2019.2\\bootstrap-vue contains both .browserslistrc and package.json with browsers',
browserslist: true } 94% asset optimization ERROR Failed to compile with 2 errors16:23:19

error in ./src/App.vue

Module build failed: BrowserslistError: E:\aawork\1work\2019.2\bootstrap-vue contains both .browserslistrc and package.json with browsers
at E:\aawork\1work\2019.2\bootstrap-vue\node_modules\_browserslist@2.11.3@browserslist\node.js:192:15
at eachParent (E:\aawork\1work\2019.2\bootstrap-vue\node_modules\_browserslist@2.11.3@browserslist\node.js:43:18)
at Object.findConfig (E:\aawork\1work\2019.2\bootstrap-vue\node_modules\_browserslist@2.11.3@browserslist\node.js:172:20)
at Object.loadConfig (E:\aawork\1work\2019.2\bootstrap-vue\node_modules\_browserslist@2.11.3@browserslist\node.js:126:37)
at browserslist (E:\aawork\1work\2019.2\bootstrap-vue\node_modules\_browserslist@2.11.3@browserslist\index.js:194:22)
at Browsers.parse (E:\aawork\1work\2019.2\bootstrap-vue\node_modules\_autoprefixer@7.2.6@autoprefixer\lib\browsers.js:61:16)
at new Browsers (E:\aawork\1work\2019.2\bootstrap-vue\node_modules\_autoprefixer@7.2.6@autoprefixer\lib\browsers.js:52:30)
at loadPrefixes (E:\aawork\1work\2019.2\bootstrap-vue\node_modules\_autoprefixer@7.2.6@autoprefixer\lib\autoprefixer.js:70:24)
at plugin (E:\aawork\1work\2019.2\bootstrap-vue\node_modules\_autoprefixer@7.2.6@autoprefixer\lib\autoprefixer.js:81:24)
at LazyResult.run (E:\aawork\1work\2019.2\bootstrap-vue\node_modules\_postcss@6.0.23@postcss\lib\lazy-result.js:277:20)
at LazyResult.asyncTick (E:\aawork\1work\2019.2\bootstrap-vue\node_modules\_postcss@6.0.23@postcss\lib\lazy-result.js:192:32)
at LazyResult.asyncTick (E:\aawork\1work\2019.2\bootstrap-vue\node_modules\_postcss@6.0.23@postcss\lib\lazy-result.js:204:22)
at E:\aawork\1work\2019.2\bootstrap-vue\node_modules\_postcss@6.0.23@postcss\lib\lazy-result.js:197:27
at <anonymous>

@ ./node_modules/_vue-style-loader@3.1.2@vue-style-loader!./node_modules/_css-loader@0.28.11@css-loader?{"sourceMap":true}!./node_modules/_vue-loader@13.7.3@vue-loader/lib/style-compiler?{"vue":true,"id":"data-v-7ba5bd90","scoped":false,"hasInlineConfig":false}!./node_modules/_vue-loader@13.7.3@vue-loader/lib/selector.js?type=styles&index=0!./src/App.vue 4:14-354 13:3-17:5 14:22-362
@ ./src/App.vue
@ ./src/main.js
@ multi ./node_modules/_webpack-dev-server@2.11.3@webpack-dev-server/client?http://localhost:8093 webpack/hot/dev-server ./src/main.js

error in ./src/components/HelloWorld.vue

Module build failed: BrowserslistError: E:\aawork\1work\2019.2\bootstrap-vue contains both .browserslistrc and package.json with browsers
at E:\aawork\1work\2019.2\bootstrap-vue\node_modules\_browserslist@2.11.3@browserslist\node.js:192:15
at eachParent (E:\aawork\1work\2019.2\bootstrap-vue\node_modules\_browserslist@2.11.3@browserslist\node.js:43:18)
at Object.findConfig (E:\aawork\1work\2019.2\bootstrap-vue\node_modules\_browserslist@2.11.3@browserslist\node.js:172:20)
at Object.loadConfig (E:\aawork\1work\2019.2\bootstrap-vue\node_modules\_browserslist@2.11.3@browserslist\node.js:126:37)
at browserslist (E:\aawork\1work\2019.2\bootstrap-vue\node_modules\_browserslist@2.11.3@browserslist\index.js:194:22)
at Browsers.parse (E:\aawork\1work\2019.2\bootstrap-vue\node_modules\_autoprefixer@7.2.6@autoprefixer\lib\browsers.js:61:16)
at new Browsers (E:\aawork\1work\2019.2\bootstrap-vue\node_modules\_autoprefixer@7.2.6@autoprefixer\lib\browsers.js:52:30)
at loadPrefixes (E:\aawork\1work\2019.2\bootstrap-vue\node_modules\_autoprefixer@7.2.6@autoprefixer\lib\autoprefixer.js:70:24)
at plugin (E:\aawork\1work\2019.2\bootstrap-vue\node_modules\_autoprefixer@7.2.6@autoprefixer\lib\autoprefixer.js:81:24)
at LazyResult.run (E:\aawork\1work\2019.2\bootstrap-vue\node_modules\_postcss@6.0.23@postcss\lib\lazy-result.js:277:20)
at LazyResult.asyncTick (E:\aawork\1work\2019.2\bootstrap-vue\node_modules\_postcss@6.0.23@postcss\lib\lazy-result.js:192:32)
at LazyResult.asyncTick (E:\aawork\1work\2019.2\bootstrap-vue\node_modules\_postcss@6.0.23@postcss\lib\lazy-result.js:204:22)
at E:\aawork\1work\2019.2\bootstrap-vue\node_modules\_postcss@6.0.23@postcss\lib\lazy-result.js:197:27
at <anonymous>

@ ./node_modules/_vue-style-loader@3.1.2@vue-style-loader!./node_modules/_css-loader@0.28.11@css-loader?{"sourceMap":true}!./node_modules/_vue-loader@13.7.3@vue-loader/lib/style-compiler?{"vue":true,"id":"data-v-469af010","scoped":true,"hasInlineConfig":false}!./node_modules/_vue-loader@13.7.3@vue-loader/lib/selector.js?type=styles&index=0!./src/components/HelloWorld.vue 4:14-369 13:3-17:5 14:22-377
@ ./src/components/HelloWorld.vue
@ ./src/router/index.js
@ ./src/main.js
@ multi ./node_modules/_webpack-dev-server@2.11.3@webpack-dev-server/client?http://localhost:8093 webpack/hot/dev-server ./src/main.js