---
{
    "title": "Format Code",
    "language": "en"
}
---

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# Format Code
To automatically format the code, clang-format is a good choice.

## Code Style
Doris Code Style is based on Google's, makes a few changes. The customized .clang-format
file is in the root dir of Doris.
Now, .clang-format file only works on clang-format-8.0.1+.

## Preparing
You should install clang-format, or you can use clang-format plugins which support by IDEs or Editors.

### Install clang-format
Ubuntu: `apt-get install clang-format` 

Mac: `brew install clang-format`

The current release is 10.0, you can specify old version, e.g.
 
 `apt-get install clang-format-9`

Centos 7: 

The version of clang-format installed by yum is too old. Compiling clang from source
is recommended.

### Clang-format plugins
Clion IDE supports the plugin "ClangFormat", you can search in `File->Setting->Plugins`
 and download it.
But the version is not match with clang-format. Judging from the options supported, 
the version is lower than clang-format-9.0.

## Usage

### CMD
`clang-format --style=file -i $File$` 

`-style=file` Clang-format will try to find the .clang-format file located in the closest parent directory of the input file. When the standard input is used, the search is started from the current directory.

`--lines = m:n` Format a range of lines. Multiple ranges can be formatted by specifying several -lines arguments.

`-i`input file

Note: filter out the files which should not be formatted, when batch clang-formatting files. 
 
 A example of how to filter \*.h/\*.cpp and exclude some dirs:
 
 Centos

`find . -type f -not \( -wholename ./env/* \) -regextype posix-egrep -regex
 ".*\.(cpp|h)" | xargs clang-format -i -style=file`
 
 Mac
 
 `find -E . -type f -not \( -wholename ./env/* \) -regex ".*\.(cpp|h)" | xargs clang-format -i --style=file`

### Using clang-format in IDEs or Editors
#### Clion
If using the plugin 'ClangFormat' in Clion, choose `Reformat Code` or press the keyboard 
shortcut.
#### VS Code
VS Code needs install the extension 'Clang-Format', and specify the executable path of 
clang-format in settings.

Open the vs code configuration page and search `clang_format`, fill the box as follows.

```
"clang_format_path":  "$clang-format path$",
"clang_format_style": "file"
```
Then, right click the file and choose `Format Document`.