tsify is slow

[JohnLouderback]

I'm wondering if I haven't made a glaring mistake, but tsify is taking around a minute and half to build our codebase's JS whereas with just Flow and Babel it would take around 7 seconds. I've also noticed that if I get any Typescript errors, I'll usually get around 6 repeated of the same error for the same line and column. Are there any caveats I should be aware of, or is tsify just slow?

[cartant]

In certain situations, tsify can be rather slow. This has a lot to do with the limited communication that's possible between Browserify and its plugins and transforms.

tsify works by compiling the TypeScript program, holding the results of the compilation in memory, and returning the compiled content to Browserify via a transform. If transform sees a file that was not part of the compilation, the cache miss will effect a re-compilation. And that can be slow.

tsify contains diagnostic logging that can be enabled using NODE_DEBUG (see https://github.com/TypeStrong/tsify/blob/master/CONTRIBUTING.md#debugging) and that will clearly show which files are causing cache misses, if they are occurring.

However, I'm not sure that's your problem. It's not clear to me what build system you are using, but looping through the results of that glob doesn't look right. Unless you are creating multiple bundles, I don't see why you need to repeatedly call browserify, etc. for each .ts and .js file.

Usually, you specify only the entry point file and Browserify will slurp up the dependent files using require - or import, for .ts files.

[HerringtonDarkholme]

Hi @cartant . I would suggest add a transpileOnly flag to tsify. Like https://github.com/TypeStrong/ts-loader#transpileonly-boolean-defaultfalse

[JohnLouderback]

@cartant I'm using Gulp. Our build process is configured to bundle multiple top level JS/TS files. Setting NODE_DEBUG=tsify appears to make no discernable difference. I don't see any further output.

[cartant]

Without knowing more about your setup, there's not much that can be said. Why are you globbing and bundling every file that matches the glob? That's looks very strange.

[cartant]

For the record, it's possible to use multiple top-level files, but you would normally add them and bundle once. You are bundling with each added, top-level file.

[cartant]

@HerringtonDarkholme Thanks. I'll bear that in mind. However, I don't have a great deal of time to allocate to this project, at the moment; I'll add it to the backlog.

[JohnLouderback]

@cartant The glob is because there top-level files are independent bundles. If there's any specific information about our build process you'd like to know, I'd be happy to share with you. Unfortunately, if I can't resolve the 7 second to 1.5 minute build time increase, TypeScript won't be an option for us. Any help would be extremely appreciated. Are minute and a half build times common for tsify?

[cartant]

The baseline to use to determine whether or not tsify is slow is tsc - the TypeScript command line compiler. For a one-off build, tsify is not going to be faster than that. If it is significantly slower, it's possible that there could an issue to address.