Untangler

Multi-language refactoring tool implemented in Java, an experimental spin-off of MenderBot.

Commands

• untangler get functions: List function definitions in a file
• untangler get references: Show symbol and declarations and reference in a file
• untangler rename: Rename a symbol and all references to it a file
• untangler add comment: Add a comment at a given line
• untangler remove comment: Remove a comment at a given line

All commands output text by default but can output machine-readable formats with arguments -o json or -o yaml.

Arguments to each subcommand can be printed with untangler <COMMAND> --help.

Status

Prototype, not ready for production use.

Support by language

Action	Python	C / C++	Java	C#	js / ts
get functions	Beta	Beta	Beta	Beta	-
get references	Beta	Beta	Beta	Beta	-
rename	-	Beta	Beta	-	-
add comment	-	Beta	Beta	-	-
remove comment	-	Beta	Beta	-	-
extract variable	-	-	-	-	-
extract parameter	-	-	-	-	-
extract field	-	-	-	-	-

Requirements (build)

• Java 16+ (GraalVM JDK20 to build static exe (Homebrew tap)

GraalVM will allow us to ship untangler static executable that does not require Java to be installed for the end user.

Running

# Set your GraalVM JDK instalation if you're using it
export JAVA_HOME=...

./gradlew installDist

build/install/untangler/bin/untangler

For easy rebuilding and running with the un shortcut, use:

alias un="./gradlew installDist -q && build/install/untangler/bin/untangler"

un get functions -f src/test/resources/hello.c

Testing

Just the unit tests:

./gradlew test

Everything:

./gradlew spotlessApply check

Coverage report in open build/reports/jacoco/test/html/index.html

Vision

• Support each of the core 6 refactorings identified by Arlo Belshee
• Support the Menderbot target languages with reliable syntax tree manipulation
• Operate independent of a language server
• Be automation-friendly, commands should have an option to output json and indicate success with exit codes, for instance

Core 6 refactorings

• Rename
• Inline
• Extract Method
• Introduce Local Variable
• Introduce Parameter
• Introduce Field

Target languages

1. Python
2. C / C++
3. Java
4. C#
5. JavaScript / TypeScript

Building native binary

This build is slower, but the resulting static executable is fast and shippable!

# Your GraalVM JDK 20 instalation
export JAVA_HOME=...

./gradlew nativeCompile

# Run with:

build/native/nativeCompile/untangler

During development, you might alias this nun for native untangler.

alias nun="build/native/nativeCompile/untangler"

If you get a reflection error, META-INF may need to be updated. Check the Gradle native image docs for more info. So far what's been needed is for META-INF/native-image/reflect-config.json to list all the classes that we will serialize to Json. Try running GenerateReflectConfig to get new json (this should eventually be a build step).

Author

👤 Ray Myers

• YouTube: Craft vs Cruft
• Twitter: @lambdapocalypse
• GitHub: @raymyers
• LinkedIn: @cadrlife

Acknowledgements

• Antlr - the leading parser generator
• JavaParser - analyze and transform Java Code
• picocli - a mighty tiny command line interface

📝 License

Copyright © 2024 Ray Myers.

This project is Apache 2 licensed.