GitHub · Pull requests · Diffs · Checked October 28, 2026

GitHub: a pull request shows every line of a file changed

Every time you press return you insert an invisible character called a line ending, and different operating systems handle line endings differently. When you collaborate with Git and GitHub, Git might produce unexpected results if, for example, you work on Windows and a collaborator has made a change in macOS; configuring Git to handle line endings avoids problems in your diffs (GitHub's configuring Git to handle line endings, checked October 28, 2026).

Why every line looks changed

Other line endings: each line of a text file ends with a line ending, so a file saved with the line endings of another operating system differs on every line, though the text you see is the same.
After a new setting: after you set core.autocrlf or commit a .gitattributes file, Git automatically changes line endings to match the new configuration, and Git may report changes to files that you have not modified.
Text or binary: Git automatically determines whether files in a repository are text or binary files; GitHub recommends marking binary files explicitly in .gitattributes, so that they are not corrupted.

What the settings do

core.autocrlf: changes how Git handles line endings on your machine. On Windows, pass true: line endings in files you check out are correct for Windows, and they are converted to Unix style when you commit. On macOS and Linux, pass input.
.gitattributes: a file in the root of the repository, committed like any other file, that sets how Git reads line endings for the files it matches. It overrides core.autocrlf for all contributors, whatever their Git settings.
Its settings: text=auto lets Git handle the files in whatever way it thinks is best; text eol=crlf always converts line endings to CRLF on checkout, and text eol=lf to LF; binary tells Git that the files are not text and not to change them, and is an alias for -text -diff.

What to do

Set it for everyone: commit a .gitattributes file with, for example, * text=auto as the default, the text files that must keep CRLF or LF, and the binary files.
Renormalize the repository: first add and commit any outstanding changes, then run git add --renormalize . to update all files on the current branch to the new configuration, check the rewritten files with git status, and commit them, as in GitHub's steps, with a message of their own.
A diff not shown at all: for a file whose changes GitHub does not show, or whitespace hidden in the review, see file diff not shown.

In IntelliJ IDEA: line endings are set aside, with a notice when they are the only change

How the GitHub support built into IntelliJ IDEA shows a file whose line endings changed, in its source (checked October 31, 2026; IntelliJ IDEA: DiffContentFactoryImpl.java, SimpleDiffViewer.java, TextDiffViewerUtil.java, DiffNotifications.kt, DiffBundle.properties):

Listed as changed: the file list is GitHub's, so a file GitHub reports as changed is in it (how the list and the diffs are made: a file diff is not shown).
Compared without line endings: when the diff reads a version as text, it converts its line endings to one form and keeps the kind it found aside. A file whose only change is its line endings therefore shows no changed lines in the side-by-side diff, with the notice Contents have differences only in line separators (Contents have differences only in line separators and encoding when the encoding changed too).

GitHub pull requests in IntelliJ IDEA

Pull Request Inbox for GitHub, a plugin by Lesstep for JetBrains IDEs 2024.1 or later, shows a pull request's reviews, checks and conversations next to the diff, and merges it with the methods the target branch allows. It lists the files GitHub reports as changed and opens each in the IDE's diff, with the file read at the merge base and at the head commit; it does not read .gitattributes, so a file whose line endings changed is listed like any other. The review inbox, diffs and conversations are free; approving, commenting, resolving and merging are Pro (US$1.50 a month, with a 30-day trial).

GitHub is a trademark of GitHub, Inc.; IntelliJ IDEA is a trademark of JetBrains s.r.o. This page is not affiliated with or endorsed by GitHub, Inc. or JetBrains.