Shebang and Modeline Detection

[thecoolwinter]

Description

Adds shebang and mode line detection to the CodeLanguage.detectLanguage function.

Shebangs are commonly used in scripting languages like python or ruby to allow the scripts to be run by the operating system by adding a "#! ..." line at the top of the file.

modelines are used by Emacs and Vim to configure editor functionality. Both have parameters for setting the file type.

CodeLanguage.detectLanguage can now detect both shebangs and modelines via the optional parameters prefixBuffer and suffixBuffer. It will check the prefix buffer for a valid shebang, and if found attempt to parse it. If no shebang is found, it will attempt to find and parse a valid modeline from either the prefix or suffix (Emacs modelines can be in the first or last 5 lines of the file).

Related Issues

• closes 🐞 Detect File Language Via shebang #46

Checklist

• I read and understood the contributing guide as well as the code of conduct
• The issues this PR addresses are related to each other
• My changes generate no new warnings
• My code builds and runs on my machine
• My changes are all related to the related issue above
• I documented my code

Screenshots

Once the changes are propagated to CodeEditTextView and CodeEdit, opened files can detect shebangs and modelines:

Python detection:

Vim modeline detecting javascript:

Node:

[bombardier200]

LGTM!