For my Google Summer of Code (GSoC) 2018 project, I wanted to make a feature for the command window of GNU Octave, that could suggest possible corrections of typographic errors to its users. Read more about it here. Such a feature can be found at many other places as well, some common examples are, The Google search, The Linux terminal, The GCC compiler, etc.
GNU Octave uses Mercurial as their version control system and because my project had to be integrated with Octave, hosting the code for my project on GitHub would have been a lot of extra work.
Therefore, the project has been hosted on Bitbucket, and just like GNU Octave, uses Mercurial as the version control system. You can read about the progress of the project here and the public repository that contains the code for this feature can be seen here. The final patch that will be merged with the main line of development of GNU Octave can be found as a file named final_work.diff in this repository, the google drive link for the patch is this.
The feature has been integrated into my clone of GNU Octave and to experience the feature first hand, currently, one has to build my clone of GNU Octave from the Bitbucket source repository linked above. The dependencies for building from source depend on the configuration of your system, details can be found here. Instructions for building the source can be found here. Hopefully, later on, the project will be merged with the main line of development and then, a simple download and installation of GNU Octave shall be enough to experience this feature.