feat: log out which files changed on HMR or watch change

[HasanAlrimawi]

This PR addresses issue #25504

Changes
When using --watch or --watch-hmr with deno serve, and when using deno run --watch then on any file specified changed, logs will be shown indicating what files changed in a numbered manner.

PS: deno run --watch-hmr already shows if the script being executed was changed.

Screenshot to show the change:

[HasanAlrimawi]

@marvinhagemeister
Can you give it a look if you have time please?

[marvinhagemeister]

Thanks for tackling this. The output already looks better than what we have today.

I noticed that when you change a single file and the HMR is applied successfully (like changing the body of a function), then the output looks like this:

HMR Replaced changed module file:///Users/marvinh/dev/test/deno-hmr/a.ts

I like that it's compact and only takes up one line. The output logged by the changes in this PR always take up at least 3 lines.

HMR File change detected! Restarting!
Files Changed:
1: "/Users/marvinh/dev/test/deno-hmr/main.ts"

How do you feel about making it more compact? Maybe something like this:

# For single file updates
HMR Restarting! File change detected: "/Users/marvinh/dev/test/deno-hmr/main.ts"

# For multiple file updates
HMR Restarting! File changes detected:
- "/Users/marvinh/dev/test/deno-hmr/main.ts"
- "/Users/marvinh/dev/test/deno-hmr/b.ts"

[bartlomieju]

I'm not really convinced that one can receive "multiple file change". We're restarting on every change and these changes are received one-by-one. I'd encourage to keep single line output and if multifile change happens only use the first one.

[HasanAlrimawi]

@marvinhagemeister
Could you please take a look at the recent changes?

[bartlomieju]

@HasanAlrimawi thanks for the PR, we'll land it for Deno 2.1.

While you're looking into watcher code, could you change the output to make messages after HMR or Watcher be printed in gray?

[bartlomieju]

Thanks!