Teddy: Automatic Recommendation For Pythonic Idiom Usage

Purit Phan-udom, Naruedon Wattanakul, Tattiya Sakulniwat, Chaiyong Ragkhitwetsagul∗, Thanwadee Sunetnanta∗, Morakot Choetkiertikul∗, Faculty of Information and Communication Technology (ICT), Mahidol University

Raula Gaikovina Kula, Nara Institute of Science and Technology (NAIST)

Introduction

Pythonic code is idiomatic code that follows guiding principles and practices within the Python community. Offering performance and readability benefits, Pythonic code is claimed to be widely adopted by experienced Python developers, but can be a learning curve to novice programmers. To aid with Pythonic learning, we create an automated tool, called Teddy, that can help checking the Pythonic idiom usage. The tool offers a prevention mode with Just-In-Time analysis to recommend the use of Pythonic idiom during code review and a detection mode with historical analysis to run a thorough scan of idiomatic and non-idiomatic code. In this paper, we first describe our tool and an evaluation of its performance. Furthermore, we present a case study that demonstrates how to use Teddy in a real-life scenario on an Open Source project. An evaluation shows that Teddy has high precision for detecting Pythonic idiom and non-Pythonic code. Using interactive visualizations, we demonstrate how novice programmers can navigate and identify Pythonic idiom and non-Pythonic code in their projects.

Pythonic and Non-Pythonic Idiom Database

Pythonic Database Set

Type	Description
Pythonic dict comprehension	Declaration of dict variable and assignment of its elements in a single statement
Pythonic list comprehension	Declaration of list variable and assignment of its elements in a single statement
Pythonic enumerate	For-loop iteration using enumerate function
Pythonic if statement	Using implicit truthfulness for if conditional statement
Pythonic file reading statement	Using with open() ... as to open a file
Pythonic set	Using set variable type to create a unique collection
Pythonic tuple	Unpacking data for multiple assignment at once
Pythonic variable swapping	Using tuple to swap values between two or more variables
Pythonic string formatting	Concatenation of multiple string formatting statements, use of .format() with placeholder(s) in a static string
Pythonic code formatting	Proper use of indentation for code blocks and writing one statement per one line

Non-Pythonic Database Set

Type	Description
Non-Pythonic dict comprehension	Separate declaration and for-loop element assignment of a dict variable
Non-Pythonic list comprehension	Separate declaration and for-loop element assignment of a list variable
Non-Pythonic enumerate	for-loop iteration without the use of enumerate
Non-Pythonic if statement	direct comparison of variable with True, False, or None in the conditional statement
Non-Pythonic file reading statement	Opening a file without using with open() as ...
Non-Pythonic set	Using for-loop to create a unique collection of item
Non-Pythonic tuple	Explicitly assigning variables with elements in a collection
Non-Pythonic variable swapping	Using a temp variable to swap values of two variables
Non-Pythonic string formatting	Sequence of one string formatting commands per one line, using ‘+’ to concatenate static string and variable(s) together, or using ‘%’ as string variable placeholder
Non-Pythonic code formatting	Using ‘;’ to put more than one statement in a single line

The full database source codes can be accessed via this link.

Ground truth data that are used to evaluate the configuration of Siamese are in this link.

Case Study on Project Flask

Prevention Mode

github.com/MUICT-SERU/flask/pull/1

Detection Mode

https://muict-seru.github.io/icsme20-teddy-tooldemo/flask.html

More Details

The full detail of the project is in this GitHub repository.