Fmt removes underscores from number literals

[CodeSandwich]

Component

Forge

Have you ensured that all of these are up to date?

• Foundry
• Foundryup

What version of Foundry are you on?

forge 0.2.0 (01325bc 2022-08-03T00:04:34.894101923Z)

What command(s) is the bug in?

forge fmt

Operating System

Linux

Describe the bug

After running forge fmt all underscores are erased from number literals. E.g.

uint256 million = 1_000_000;

is formatted into

uint256 million = 1000000;

which degrades readability.

[mattsse]

cc @rkrasiuk @jpopesculian

[rkrasiuk]

this behavior was intentional and waiting for fmt config. now, we can introduce it as an option to either preserve, force or remove underscores

[onbjerg]

@rkrasiuk feel free to ping me or open an issue in the book if you add more config stuff so we can ensure that part is updated, still need to write formatter chapter other than that