diff --git a/packages/react-scripts/template/README.md b/packages/react-scripts/template/README.md index 5290f7f2fff..4224a851669 100644 --- a/packages/react-scripts/template/README.md +++ b/packages/react-scripts/template/README.md @@ -65,6 +65,7 @@ You can find the most recent version of this guide [here](https://github.com/fac - [Troubleshooting](#troubleshooting) - [`npm test` hangs on macOS Sierra](#npm-test-hangs-on-macos-sierra) - [`npm run build` silently fails](#npm-run-build-silently-fails) + - [`npm run build` fails on Heroku](#npm-run-build-fails-on-heroku) - [Something Missing?](#something-missing) ## Updating to New Releases @@ -1176,7 +1177,21 @@ GitHub Pages doesn't support routers that use the HTML5 `pushState` history API ### Heroku Use the [Heroku Buildpack for Create React App](https://github.com/mars/create-react-app-buildpack).
-You can find instructions in [Deploying React with Zero Configuration](https://blog.heroku.com/deploying-react-with-zero-configuration). +You can find instructions in [Deploying React with Zero Configuration](https://blog.heroku.com/deploying-react-with-zero-configuration). + +#### Resolving "Module not found: Error: Cannot resolve 'file' or 'directory'" + +Sometimes `npm run build` works locally but fails during deploy via Heroku with an error like this: + +``` +remote: Failed to create a production build. Reason: +remote: Module not found: Error: Cannot resolve 'file' or 'directory' +MyDirectory in /tmp/build_1234/src +``` + +This means you need to ensure that the lettercase of the file or directory you `import` matches the one you see on your filesystem or on GitHub. + +This is important because Linux (the operating system used by Heroku) is case sensitive. So `MyDirectory` and `mydirectory` are two distinct directories and thus, even though the project builds locally, the difference in case breaks the `import` statements on Heroku remotes. ### Modulus @@ -1270,6 +1285,11 @@ There are also reports that *uninstalling* Watchman fixes the issue. So if nothi It is reported that `npm run build` can fail on machines with no swap space, which is common in cloud environments. If [the symptoms are matching](https://github.com/facebookincubator/create-react-app/issues/1133#issuecomment-264612171), consider adding some swap space to the machine you’re building on, or build the project locally. +### `npm run build` fails on Heroku + +This may be a problem with case sensitive filenames. +Please refer to [this section](#resolving-module-not-found-error-cannot-resolve-file-or-directory). + ## Something Missing? If you have ideas for more “How To” recipes that should be on this page, [let us know](https://github.com/facebookincubator/create-react-app/issues) or [contribute some!](https://github.com/facebookincubator/create-react-app/edit/master/packages/react-scripts/template/README.md)