Webpack doesn't notify NativeScript CLI when there is a compilation error. So, NativeScript CLI build the app, install it on device and start it. In most cases the application crashes runtime as the webpack compilcation is not successful. Most probably there would be a red/yellow message in the console printed during the compilation. The users don't see the error message as there is too much log outputed in the console. They don't understand the exact reason why their app crashes runtime.
Webpack has a mechanism to skip the emitting phase whenever there are errors while compiling. This can be achieved using optimization.noEmitOnErrors property as it is described here. This PR adds noEmitOnErrors property in all webpack.config files:
The default value is based on noEmitOnError property from tsconfig.json for angular and typescript projects
The default value is true for javascript and vue projects.
Also this PR fixes the following problems:
Check for syntactic errors when running webpack compilation in ts projects
Currently ts-loader is started in transpileOnly mode and webpack plugin (ForkTsCheckerWebpackPlugin) runs TypeScript type checker on a separate process in order to report for compilation errors. By default the plugin only checks for semantic errors and adds them to compilation.errors as can be seen here. On the other side, webpack relies on compilation.errors array when deciding if should skip emitting phase. However, ts-loader used in transpileOnly mode still reports syntactic errors but adds them to compilation.warnings. This is a problem, as actually the compilation is not stopped when there is a syntactic error. Setting checkSyntacticErrors: true will ensure that ForkTsCheckerWebpackPlugin will check for both syntactic and semantic errors and after that will be added to compilation.errors.
Respect noEmitOnError from tsconfig.json when compiling ts projects
The hmr generates new hot-update files on every change and the hash of the next hmr update is written inside hot-update.json file. Although webpack doesn't emit any files, hmr hash is still generated. The hash is generated per compilation no matter if files will be emitted or not. This way, the first successful compilation after fixing the compilation error generates a hash that is not the same as the one expected in the latest emitted hot-update.json file. As a result, the hmr chain is broken and the changes are not applied.
[ ] There is an issue for the bug/feature this PR is for. To avoid wasting your time, it's best to open a suggestion issue first and wait for approval before working on it.
Webpack doesn't notify NativeScript CLI when there is a compilation error. So, NativeScript CLI build the app, install it on device and start it. In most cases the application crashes runtime as the webpack compilcation is not successful. Most probably there would be a red/yellow message in the console printed during the compilation. The users don't see the error message as there is too much log outputed in the console. They don't understand the exact reason why their app crashes runtime.
Webpack has a mechanism to skip the emitting phase whenever there are errors while compiling. This can be achieved using
optimization.noEmitOnErrorsproperty as it is described here. This PR addsnoEmitOnErrorsproperty in all webpack.config files:noEmitOnErrorproperty fromtsconfig.jsonforangularandtypescriptprojectstrueforjavascriptandvueprojects.Also this PR fixes the following problems:
Currently
ts-loaderis started intranspileOnlymode and webpack plugin (ForkTsCheckerWebpackPlugin) runs TypeScript type checker on a separate process in order to report for compilation errors. By default the plugin only checks for semantic errors and adds them tocompilation.errorsas can be seen here. On the other side, webpack relies on compilation.errors array when deciding if should skip emitting phase. However,ts-loaderused intranspileOnlymode still reports syntactic errors but adds them tocompilation.warnings. This is a problem, as actually the compilation is not stopped when there is a syntactic error. SettingcheckSyntacticErrors: truewill ensure thatForkTsCheckerWebpackPluginwill check for both syntactic and semantic errors and after that will be added tocompilation.errors.noEmitOnErrorfromtsconfig.jsonwhen compilingtsprojectsThe problem is in
ForkTsCheckerWebpackPluginand in the way it is integrated with webpack hooks - https://github.com/TypeStrong/fork-ts-checker-webpack-plugin/pull/337.The
hmrgenerates new hot-update files on every change and the hash of the next hmr update is written inside hot-update.json file. Although webpack doesn't emit any files, hmr hash is still generated. The hash is generated per compilation no matter if files will be emitted or not. This way, the first successful compilation after fixing the compilation error generates a hash that is not the same as the one expected in the latest emitted hot-update.json file. As a result, the hmr chain is broken and the changes are not applied.Rel to: https://github.com/NativeScript/nativescript-cli/issues/3785
PR Checklist
What is the current behavior?
What is the new behavior?
Fixes/Implements/Closes #[Issue Number].