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• The PR title follows our guidelines: https://github.com/NativeScript/NativeScript/blob/master/tools/notes/CONTRIBUTING.md#commit-messages.
• 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.
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• All existing tests are passing: https://github.com/NativeScript/NativeScript/blob/master/tools/notes/DevelopmentWorkflow.md#running-unit-tests-application.
• Tests for the changes are included - https://github.com/NativeScript/NativeScript/blob/master/tools/notes/WritingUnitTests.md.

What is the current behavior?

When there's a compilation error, webpack may emit files (depending on how it's configured), however the CLI is never notified of these files, so they are not synced to the device. This is generally the right behavior however there are cases where this isn't ideal, most notably with HMR. When there's a compilation error, a new hash is assigned to the compilation, and files are written but never synced. After fixing the error, yet another hash is generated, however the app will not be able to apply hmr because it must first apply the "errored" hash, and then the fixed one - it works like a sequential chain, and if we don't emit the errored chain links, we break HMR.

What is the new behavior?

The CLI is notified regardless of errors in the compilation. This may crash the app - however that's expected in some cases. In other cases this should fix HMR breakage after a single error during development.

References:

• When the application has errors HMR slows down more and more nativescript-vue/nativescript-vue#1013