Remove unused classes

[flunderpero]

We use custom generator code to generate Typescript classes from a Protobuf definition. We keep all classes in a single, rather big module. A class looks roughly like this:

class MyEntity {
    // Some static constants
    static string HTTP_METHOD = "GET"

    // Properties
    public name: string

    // Static entry point for deserialization
    static _from_pb() { ... }

    to_pb() { ... }
}

When bundling the code for the web-app, all classes are preserved in the output whether they are used or not.

We build like this:

await esbuild(
{
        entryPoints: ["index.ts"],
        outdir: "out",
        format: "esm",
        tsconfig: "./tsconfig.json"),
        sourcemap: "external",
        minifyIdentifiers: false,
        minifySyntax: true,
        minifyWhitespace: true,
        bundle: true,
        keepNames: true,
        target: "es2017",
})

Edit: I just checked: Some classes are removed from the output, but I cannot see any pattern.

[flunderpero]

If I remove the static "constants" (HTTP_METHOD) then the unused classes are removed from output.

[flunderpero]

I tried to generate the Typescript code like this static HTTP_METHOD = <const>"GET" but it did not change anything. I know that esbuild only works on JS and ignores Typescript's syntax.

Is there a chance to make this work?

[flunderpero]

But even after I "fix" the static constants there are still unused classes in the resulting bundle.

[evanw]

I believe this is a duplicate of #175. Closing as a duplicate.