Kotlin adoption on the Android open source community

This repository contains the implementation used for the post Kotlin adoption on Android open source community published on Medium.

Datasets

creations_scrapper fetchs the number of Github repositories created every month from 2016-02-15 (Kotlin 1.0 release date) to 2019-01-15, creating four distinct categories:

Category	Scope	Main Language	Github Query
Android + Kotlin	Only Android projects	Kotlin	android language:kotlin
Android + Java	Only Android projects	Java	android language:java
Not Android + Kotlin	Not Android projects	Kotlin	NOT android language:kotlin
Not Android + Java	Not Android projects	Java	NOT android language:java

Thus, Android repositories are those which contain the android word in their title, description or readme file. Alike, not Android repositories are those which does not contain the android word in their title, description or readme. This is a very coarse way of filtering them, but it's also a pretty convenient one. Suggestions are welcome.

migrations_scrapper fetchs those active Github Android repositories which have been and have not been migrated to Kotlin.

For getting the migrated repositories, it retrieves those Java repositories which were created before Kotlin 1.0 was released and now their main language is Kotlin (I was not able to find what percentage it represents, I'd guess 50%?). The Github query used is: android language:kotlin created:<2016-02-15 pushed:>2019-01-01.

In like manner, to get those which have not been (yet?) migrated, the script retrieves those Java repositories which were created before Kotlin was released and their main language is still Java. The Github query used is: android language:java created:<2016-02-15 pushed:>2019-01-01.

The main limitation of this approach is that all the Java repositories which were created after Kotlin was released and migrate to Kotlin after that point are ignored. And also that early native Kotlin repositories would be considered as migrations.

Data analysis

This clumsy study aims to evaluate the adoption of the Kotlin programming language on the Android open source community. To do so, it addresses several points by which descriptive and comparative analyses will put into perspective the question. Both creations_DEA and migrations_DEA address these points:

1. Compare the ratio of Android repositories created in Kotlin vs Java in a monthly bases and check if it shows an increasing/decreasing trend.
2. Compare the previous rate with the not Android community one.
3. Evaluate if the public support from Google had any inpact in the previous rate.
4. Determine how many active Android repositories have been migrated from Java to Kotlin.
5. Check if the repositories migrated show any common attributes (popularity and size).