What is a .editorconfig?

The .editorconfig file is a meta file that basically provides rules that your particular IDE or editor should follow.
Including Sublime, Atom, IntelliJ, etc.

what rules can you specify in the .editorconfig file?

There is a complete list of properties hat you can read yourself, but the more common options are:

• indent_style
• indent_size
• insert_final_newline
• trim_trailing_whitespace

My favorite, of course, being the first, and second options. You are able to specify something like

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[*]
indent_style = space
indent_size = 2

Depending on where the .editorconfig file is, dictates which directories are affected. Here is my .editorconfig file that exists within my ~/workspace directory (where i house ALL projects)

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root = true

[*]
indent_style = space
indent_size = 2
end_of_line = lf
charset = utf-8
trim_trailing_whitespace = true
insert_final_newline = true

[*.md]
trim_trailing_whitespace = false

[*.java]
indent_style = space
indent_size = 4
continuation_indent_size = 0

IntelliJ 14 and .editorconfig

With the release of IntelliJ 14, came with it the capability to actually READ this .editorconfig file.. Unfortunately that also came with some baggage. IntelliJ was reading my ~/workspace/.editorconfig config file while i was editing ~/workspace/java-project. Without that [*.java] piece, IntelliJ was defaulting all Java files to 2 spaced. Note the place, too! After some debugging, I noticed that if you put anything before the [*], it will be overridden by the [*] so if you are going to specify an extension, make sure you put this bit after the [*].

After some quick google-fu, I had also found that IntelliJ actually can look for another attribute. continuation_indent_size. Now THIS property is extremely important if you are doing something in java like method chaining

Before that method, I was getting results like:

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object
    .method()
    .anotherMethod()

When in fact i wanted:

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object
.method()
.anotherMethod()

root = true

Within the .editorconfig file, there is also an option called root. It defaults to false, but when it’s set to true, then this .editorconfig will apply recursively.

In my example, my workspace looks like:

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$ ls -a $WORKSPACE
.
..
.editorconfig
some-project/
some-other-project/
yet-another-project/

With root being true, it will apply to all projects. If you wanted, you could of course override a specific project by putting an .editorconfig file in the specific project directory.

All-in-all….

I think this .editorconfig file is an amazing tool, and can help you, as a programmer, keep your code universal, and same format all the way around.