fix: make $inspect logs come from the callsite

[Rich-Harris]

Closes #16998. This is the least invasive version of the solution — by (effectively) doing this...

-$inspect(stuff)
+$inspect(stuff).with((...args) => console.log(...args));

-$inspect(stuff).with(console.trace);
+$inspect(stuff).with((...args) => console.trace(...args));

...we make the log come from the $inspect(...) callsite rather than the module containing the inspect helper — instead of this...

...we get this:

We could go further. If we updated the inspect function thusly...

untrack(() => {
-  inspector(initial ? 'init' : 'update', ...snap);
+ inspector(...snap);
+ if (!initial) console.log(get_stack('UpdatedAt'));
});

...then we would get this result:

(The label has to end with the string Error or it doesn't get formatted/sourcemapped correctly, hence UpdatedAtError.)

You could certainly make a case for that being the default. I also wonder if we should get rid of the init tag during SSR, or replace it with $inspect or something.

Thoughts?

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🦋 Changeset detected

Latest commit: e6242e6

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[github-actions]

Playground

pnpm add https://pkg.pr.new/svelte@17001

[paoloricciuti]

A couple of maybe silly comments but this looks very noice.

[pngwn]

I like it very much!!

I can already sense my frustrations melting away.

[pngwn]

I also like the update at error thing. That would be very useful imo! Although people might complain and want a way to 'quieten' it.

[Rich-Harris]

Perhaps the stack trace thing is the default but if you use with(...) you don't get that?

[pngwn]

Yeah, I think that makes sense and is a nice switch to give users control.

[svelte-docs-bot]

Preview: https://svelte-dev-git-preview-svelte-17001-svelte.vercel.app/