Range formatting broken since v6

[uncaught]

Your Environment

• Prettier version: 3.8.1
• node version: [24.x.x]
• package manager: [npm@11, pnpm@10]
• IDE: [Webstorm, PhpStorm, CLI]

Describe the bug

Formatting with a range adds extra empty lines after the import statements. Jetbrains IDEs use this heavily, which breaks the developer experience.

To Reproduce

I have created a reproducer:

git clone git@github.com:uncaught/trivago-prettier-plugin-sort-imports.git
cd trivago-prettier-plugin-sort-imports
npm i
npm run prettier -- --range-start=0 --range-end=53 hello.js

Expected behavior

There should only be one empty line between the import and the following code.

Actual behavior

There are four empty lines between import and following code.

Screenshots, code sample, etc

See https://github.com/uncaught/trivago-prettier-plugin-sort-imports

Configuration File (cat .prettierrc, prettier.config.js, .prettier.js)

export default {
  plugins: ["@trivago/prettier-plugin-sort-imports"],
};

Contribute to @trivago/prettier-plugin-sort-imports

• I'm willing to fix this bug 🥇

[castral]

Just fyi this is easy to repro in the unit tests:

in test-setup/run_spec.mjs

    return prettier.format(
        src,
        Object.assign(
            {
                rangeStart: 0,
                rangeEnd: src.length - 1,
                filepath: filename,
            },
            options,
        ),
    );

It seems whenever the prettier plugin is set to parse any amount less than the full source input will cause it to insert extra new lines.

[pvds]

Same happens with prettier-plugin-sort-imports, there is some more relevant info in that issue.

Unfortunately I don't have time to fix this bug but I tried to do a short root cause and possible suggested fix

What broke / root cause

The plugin forces import spacing by inserting its own blank-line markers (effectively writing \n\n around the import block).
With full-file formatting, Prettier later normalizes whitespace so you still end up with one blank line.

With --range-start/--range-end (JetBrains uses this a lot), Prettier does not do the same global newline cleanup across the formatted/unformatted boundary. So the plugin’s \n\n gets merged with the existing newline(s) after imports and you get extra empty lines.

Fix (recommended)

Respect range formatting: only run the import-sorting + newline injection when the formatted range overlaps the import block.

Implementation sketch:

• find importsStart = min(import.start) and importsEnd = max(import.end)
• if options.rangeStart/rangeEnd are set and rangeEnd <= importsStart or rangeStart >= importsEnd, return original text (don’t touch imports)

This keeps “Optimize Imports” working (range includes imports) and stops “format selection” elsewhere from adding blank lines after imports.

Fallback fix

If you can’t skip in range mode, normalize newlines only at the join point (end of imports / start of rest of file) so it can’t create \n\n\n....