Tukukkk

IntelliJ Idea 13 has a feature labeled Compare with Clipboard. This feature compares the current open file with a version that you have copied into your clipboard. It's a great, easy way to compare and merge two files easily. It can also be used to compare two arbitrary blocks of code. Can't figure out why one block works and another does not? Use this feature.

This option is present under View > Compare with Clipboard. I assigned an easy to remember keyboard shortcut to give me quick access to this feature.

Select 2 files in Project panel and press CTRL + D.

Yes you can (of course, if we are talking about text files). But probably you will need to create some project (just for opening there files).

Then your steps will be:

1) Add to created project file#1 and file#2.

2) Open file#1 in editor

3) Right click mouse in left menu (project files browser) on file#2 and find menu-item Compare File with Editor.

That's all. After p.3) a comparison windows will be opened.

In order to compare two files that both aren't in the project, the following works for me in IntelliJ IDEA Ultimate 14.1.7 on Windows:

1. Open the first file in the IDE (either by dragging from Windows Explorer into the window, or by File / Open).


2. In the view menu, choose "Compare With…"


3. In the "Select Path" dialog that appears, select the second file (either directly, or by dragging from Windows Explorer into the dialog).

It then opens up in the traditional file comparison pane. If you try to edit one of the files, it presents the usual "Are you sure you want to edit a file that's not in your project" dialog, which one can accept if that's what one is trying to do.

From the terminal, you can use the idea launcher directly like so:

# Windows

idea.exe diff path1 path2



# MacOS/Linux

idea diff path1 path2

At least for MacOS (I'm not certain of Windows), if you've created the Command-line Launcher via "Tools -> Create Command-line Launcher..." it's as simple as the following:

# Create some files to diff

echo "This is line 1" > file1.txt

echo "This is line 2" > file2.txt



# Diff with IntelliJ

idea diff file1.txt file2.txt

Note this works with other JetBrains applications as well; for example, using WebStorm or PyCharm:

# Diff with WebStorm

webstorm diff file1.txt file2.txt

# Diff with PyCharm

charm diff file1.txt file2.txt

Reference

In IntelliJ IDEA 2018.2, you can open an empty Differences Viewer and paste any text you want to compare in its left and right panels. The new Open Blank Diff Viewer action can be found in the Find Action dialog.

Since 2018.2, IntelliJ has officially supported it:

For windows: Ctrl + Shift + A, then type "Open Blank Diff Viewer"

For Mac: Cmd + Shift + A then type "Open Blank Diff Viewer"