deno fmt double format issue with single line for stmt with call expr with arrow function argument

[KnorpelSenf]

I would expect that for any code base the command deno fmt && deno fmt --check succeeds. However, this is not the case, as the following example illustrates.

$ cat file.ts # badly formatted file
const buttonCount = 10;

function foo() {
  for (let i = 0; i < buttonCount; i++) { range.text(i.toString(), (ctx) => ctx.reply(`${i} selected`));
  }
}
$ deno fmt --check file.ts

from /tmp/file.ts:
4 | -  for (let i = 0; i < buttonCount; i++) { range.text(i.toString(), (ctx) => ctx.reply(`${i} selected`));
4 | +  for (let i = 0; i < buttonCount; i++) {
5 | +    range.text(i.toString(), (ctx) =>
6 | +      ctx.reply(`${i} selected`));
7 | -
8 | -
9 | +

error: Found 1 not formatted file in 1 file
$ deno fmt file.ts 
/tmp/file.ts
Checked 1 file
$ deno fmt file.ts --check

from /tmp/fie.ts:
5 | -    range.text(i.toString(), (ctx) =>
6 | -      ctx.reply(`${i} selected`));
5 | +    range.text(i.toString(), (ctx) => ctx.reply(`${i} selected`));

error: Found 1 not formatted file in 1 file
$ deno fmt file.ts 
/tmp/file.ts
Checked 1 file
$ deno fmt file.ts --check
Checked 1 file

[ghost]

@dsherret @KnorpelSenf

When troubleshooting the following using the order of command, I do not receive the same errors that you are receiving. Seems to be working fine for me. I am running Windows 11 and executing via Powershell running the trunk version as it currently stands today. You are saying that you entered the commands in this order and had to run deno fmt twice?

cat file.ts
deno fmt --check file.ts
deno fmt file.ts
deno fmt --check file.ts

cat file.ts
const buttonCount = 10;

function foo() {
  for (let i = 0; i < buttonCount; i++) { range.text(i.toString(), (ctx) => ctx.reply(`${i} selected`));
  }
}

cargo run -- fmt --check .\file.ts
4 | -  for (let i = 0; i < buttonCount; i++) { range.text(i.toString(), (ctx) => ctx.reply(`${i} selected`));
4 | +  for (let i = 0; i < buttonCount; i++) {
5 | +    range.text(i.toString(), (ctx) =>
6 | +      ctx.reply(`${i} selected`));
6 | -}
8 | +}
9 | +

PS C:\Code\Deno\deno> cargo run -- fmt .\file.ts
    Finished dev [unoptimized + debuginfo] target(s) in 0.72s
     Running `target\debug\deno.exe fmt .\file.ts`
C:\Code\Deno\deno\file.ts
Checked 1 file

PS C:\Code\Deno\deno> cargo run -- fmt --check .\file.ts
    Finished dev [unoptimized + debuginfo] target(s) in 0.72s
     Running `target\debug\deno.exe fmt --check .\file.ts`
Checked 1 file

[0f-0b]

These commands work now because #14314 changed deno fmt to retry until the formatting is stable. The underlying issue remains unresolved and can still be observed when formatting the file in an editor with deno lsp.

[KnorpelSenf]

@0f-0b does that actually mean that deno fmt does one useless pass over all files? In most cases, this would mean that it makes twice as many passes as needed. Isn't that a fairly large performance overhead?

[lucacasonato]

deno fmt does not exhibit this behaviour anymore because we format until the result is stable. Upstream bug is tracked in dprint/dprint-plugin-typescript#670