Support --stopBuildOnErrors CLI Flag for @nx/js/typescript plugin

[Csszabi98]

Description

Typescript 5.6 introduced a new default behavior related to how typescript builds downstream projects when an upstream project build fails (Typescript 5.6 Allow --build with Intermediate Errors). The release also added a new CLI flag (--stopBuildOnErrors) which can be used together with --build, to replicate the default behavior from prior versions, which as the article describes is still useful in some cases (i.e.: for tightly coupled projects or CI environments).

Problem statement

Since NX encourages tsconfig project reference based setups, and these involve creating a dedicated tsconfig.spec.json, file for each project with tests, this flag can be extremely useful since if the tsconfig.lib.json based build fails, tsconfig.spec.json will start to produce a lot of error TS6305: Output file 'test-dependency.d.ts' has not been built from source file errors.

Proposed changes

Considering the default settings of @nx/js/typescript plugin in nx.json:

  "targetDefaults": {
    "@nx/js:tsc": {
      "cache": true,
      "dependsOn": ["^build"],
      "inputs": ["default", "^default"]
    }
  },

It would be ideal to shortcurcuit per package typecheck/build jobs as well by default, not just the cross package typecheck/build jobs, while keeping this configurable for anyone who wants a different behavior who is on Typescript 5.6+ (anyone below that version already gets the proposed behavior).

Thus I propose to add a new stopBuildOnErrors option for both the typecheck and the build options interface, while setting the default value to:

• true for typecheck
  • Downstream project type errors would just spiral out anyway, so it is most probably best to shortcurcuit the job by default
• true for build
  • This one is tricky, on one hand if a project is built using the tsc plugin, it wouldn't be ideal to not produce a build output when there are type only error, since during development it is desired to see instant feedback in typical workflows such as HMR and incremental builds, but on the other, there is no easy way to tell by the tsc output if emitting did happen or not (tsc still reports the errors to stio during the build when perfectly sound JS output is produced) , so it is hard to determine the exact result of the CLI execution. Due to this for simplicity I think it would be best to set this to true as well, since NX just invokes the tsc CLI, and this is as much as can be done through it at the moment.

The option should be ignored for projects running with <Typescript 5.6, since the CLI flag is not supported below that version.

Individual repositories could still build with errors while setting stopBuildOnErrors to false, and removing dependsOn from the plugin targetDefaults.

Additional considerations

The noEmitOnError tsconfig option could be used to drive this behavior (false by default), but that would add a lot of extra complexity involving tsconfig parsing and potential extends clause resolution, also separate build jobs for each tsconfig with a different value set, so it is probably overkill.