TL;DR

The released @taplo/lib contains a 35.6MB index.js, which is too big.

The cause seems to be the config debug: process.env["RELEASE"] !== "true" is not working as expected in CI.

Details

My friend and I want to use @taplo/lib in our projects, but 35.6MB is too big. So, I did some simple tests to try to find out why.

Compile taplo-wasm directly with Cargo

Since @taplo/lib includes the compiled wasm of taplo-wasm, I use Cargo to compile the crate directly to see the file size of the wasm. Here are the results:

$ ls target/wasm32-unknown-unknown/debug -alh
-rwxrwxr-x   2 duskmoon duskmoon  30M Aug 27 03:14 taplo_wasm.wasm

$ ls target/wasm32-unknown-unknown/release/ -alh
-rwxrwxr-x   2 duskmoon duskmoon 5.6M Aug 27 03:18 taplo_wasm.wasm

If the wasm is compiled in release mode, it should be about 6MB instead of 35.6MB. So I assume the configuration is incorrect.

Compile @taplo/lib with modified config

I modified rollup.config.mjs to set debug to false. This ensures the code is built in release mode. And here is the output:

$ ls dist -alh
total 6.6M
drwxrwxr-x 2 duskmoon duskmoon 4.0K Aug 27 03:14 .
drwxrwxr-x 4 duskmoon duskmoon 4.0K Aug 27 03:17 ..
-rw-rw-r-- 1 duskmoon duskmoon 4.8K Aug 27 03:18 index.d.ts
-rw-rw-r-- 1 duskmoon duskmoon 6.5M Aug 27 03:18 index.js

The output index.js is only 6.5MB.

The CI config

In the releases.yaml, the step to build and publish is:

      - name: Publish to NPM
        uses: nick-fields/retry@v3
        if: github.event_name == 'push'
        with:
          max_attempts: 3
          retry_wait_seconds: 300
          timeout_minutes: 60
          command: cd js/lib && yarn install && yarn publish
        env:
          NODE_AUTH_TOKEN: ${{ secrets.NPM_TOKEN }}

We might need to add RELEASE: true to the env section to use the release mode.