Formatting fails for entire file when a line contains only whitespace between two comments

[glitcher255]

Per Ryan's suggestion here I am reposting this. This bug still occurs in typescript-go version 0.20260427.1

💻 Code

  const x = "wont format"
//
 
//

• Notice the white space in line 3 between the two comments
• Attempt to format (in VS code by shift + alt + F)
• Notice how line 1 will not indent, this affects the entire file

This bug is difficult to reproduce if you have the "files.trimTrailingWhitespace" option enabled, as it will remove the whitespace in line 3 on save allowing formatting to work again as intended

This affects both TypeScript and JavaScript files

🕗 Version & Regression Information

• This changed between versions 4.5.5 and 6.0.3 (incl dev.20260416 nightly) incl (tsgo 0.20260427.1)
• This is the behavior in every version I tried, and I reviewed the FAQ for entries about formatting and indentation

⏯ Playground Link

https://www.typescriptlang.org/play/?ts=6.0.3#code/AQYw9gdgzgLsAewC8wBEB3ScBmYBOAtgIYyoBQA9BWcJRUA

🙁 Actual behavior

The formatting for the entire file fails silently. No lines are formatted or indented.

🙂 Expected behavior

The formatter should indent code correctly (const x in line 1)

Additional information about the issue

Issue does not affect /* */ only // comments