My Google Summer of Code project with Submitty is to revamp the count static analysis tool. count tool is used in Submitty to verify that the student submissions contains specific language features. The existing count tool did not support some new python features and was not working correctly for C/C++ programs.

The new count tool implementation is based on tree-sitter and uses an Abstract Syntax Tree generated from tree-sitter. Implementation of this new tool is carried out in the AnalysisToolsTS repository.

Initially there was an implementation of count tool with basic functionality using tree-sitter Javascript bindings. I first tried to integrate this implementation to the Submitty autograding commands. Unfortunately this was not working due to system call filtering which was preventing a nodeJS program from running in autograding.

Next I tried to implement count tool using the tree-sitter C-API. I first verified that it was possible to use the C-API implementation with Submitty autograding without running into runtime limits or system call filtering. I initially added support for counting C, C++ and Python. Later I added support for Java.

While working on this project I got to work with C, C++, bash and python. I wrote few github actions which does C++ static analysis of the source code, Shell checks and run tests.

Documentation for the new command is added to the website.

I also got the chance to work with docker container. Submitty autograding can be run in a docker container. The dockerfiles relevant to these docker containers had to be updated to the include the new count command. To keep the size of the docker images minimal it was decided only to include the binaries in docker images. Therefore I created a new github action in the AnalysisToolsTS repo which builds binaries from the source code when a new release is made. These binaries were then used in the docker images.

Main Pull requests in AnalysisToolsTS:

• [Feature:Autograding] tree-sitter c-api
• [Feature:Autograding] Add Java counting
• [Feature:Developer] Build binaries on release

Other contributions

While working on the count command, I also worked on autograding features and bugfixes in Submitty main repository.

BugFixes

• [Bugfix:Autograding] Success, information messages not shown
• [Bugfix:Autograding] Random input-output build
• [Bugfix:InstructorUI] Peer graders grading themselves
• [Bugfix:TAGrading] Nav buttons not entirely clickable
• [Bugfix:TAGrading] Fix broken Home link in TA grading
• [Bugfix:TAGrading] Fix turning off random order
• [Bugfix:Submission] Fix bad breadcrumb link for peer grading
• [Bugfix:CourseMaterials] Restrict course material for no section

Features

• [Feature:Autograding] Tolerance check in diff validator
• [Feature:Autograding] Environment variables in config.json
• [Feature:Autograding] Autograding command json file
• [Feature:Autograding] Add comment counting

I also got the chance to review Pull requests. This was my first experience with reviewing pull requests

Acknowledgement:

I am grateful for the guidance and advices received from my mentors Barbara Cutler and William Allen. I always got quick responses on my queries and I got the resources and advices I needed to work with. I am also grateful for the RPI students and fellow GSOC-contributors who worked on Submitty during the summer. I had a wonderful time working on this project and gained valuable experience.