Open boenrobot opened 4 years ago
This is something very important to me also. Being able to "hook" code to different life cycle events of the typescript compiler especially in watch mode will make the compiler much-much flexible tool. I fancy a "pre-compile", "post-compile" hooks probably "change-detected" hook. In pre-compile I might opt to "git pull" some submodules, and in "post-compile" I might copy some additional files around .. all this out of the compiler scope but totally in-scope for my build/test/deploy cycles. To make everything efficient a "plugins" should be "loaded" in the tsc node runtime as compilation in watch mode will have huge penalties starting new external nodejs env just to run some simple tasks .. also waiting for this tasks to finish will be too much work compared to await-ing a call to "plugin" exported function. The perceived slowdown of the build process is something I'm willing to pay for the immense convenience this will bring to my workflow
Also as for "who will use this feature": take a look at tsc-watch a tool that solves the discussed problem with nearly 200K weekly downloads. And only god knows how many people a efficiently solving the problem with other tools. Think of the miens popularity of Maven and its plugins
Search Terms
Suggestion
Allow a ts file to react to actions performed by tsc while it is running in
--watch
mode. This can be done by having that file export specific members of specific known types that tsc will execute at the appropriate time.Use Cases
I would like to automatically regenerate an index.ts file before letting tsc proceed with its normal compilation that would include the now altered index.ts.
In one of my projects, I would also want to restart a server after compilation. Others may want to do other build related tasks, such as re-running a subset of tests after build for example.
Examples
Given a command line
tsc --build --watch --watchHook ./watcher.ts
and the following watcher.ts file:
I would like tsc to behave as described in the watcher.ts file. As with most TS settings, there should be an analog in the tsconfig.json file, where the path to the hooks file is relative to the tsconfig.json file.
Currently, in order to do these sorts of things, one has to use a separate builder like gulp, which is somewhat complex to use for projects that use project references.
Checklist
My suggestion meets these guidelines: