Top-level await detection doesn't take into account dead code elimination

[fabiospampinato]

Trying to bundle the following code throws:

if ( false ) {
  await foo ();
}

But esbuild should realize that there's not actually any top-level await there, because the await is unreachable.

This detail not being supported makes it a bit more annoying to create a module that works in different environments but that top-level awaits in only one of them.

[evanw]

Interesting suggestion. I can't think of any negative consequences of doing this, so I think this sounds reasonable.

Edit: Well, I think it should probably still be respected for the purposes of making the file be considered an ES module. So that means no module or exports and also implying strict mode.

[fabiospampinato]

That was quick 😁 thank you!