CONTRIBUTING.md

Contributing to Prettier

To get up and running, install the dependencies and run the full build:

yarn
yarn ci

You can also inspect the other available dev flows scripts:

yarn run

Linking the java-parser to the printer

If you want to use the main java-parser for the prettier-plugin-java (printer), you will need to link it by running these commands in the root folder:

cd packages/java-parser
yarn link
cd ../prettier-plugin-java
yarn link java-parser

To unlink the java-parser, run the following command inside packages/prettier-plugin-java.

yarn unlink java-parser

Testing your changes

java-parser

In this section, we suppose you are in the packages/java-parser folder.

When working on the parser, you can test the java-parser inside scripts/single-sample-runner.js. This is a simple way to check the impact of your changes on the built CST. You can then print the CST with this code:

console.log(
  JSON.stringify(
    resultingCST,
    (key, value) => (key !== "START_CHARS_HINT" ? value : undefined),
    2
  )
);

You can also run the parser tests with the following command:

yarn test

It will basically clone some java repositories and try to parse every java file.

prettier-java-plugin

In this section, we suppose you are in the packages/prettier-plugin-java folder.

If you would like to check the impact of your changes on a sample code, edit the scripts/single-printer-run/_input.java file and run

node scripts/update-test-output.js -single

The prettified code will be output in scripts/single-printer-run/_output.java.

It is also possible to prettify an entire repository by running the following command:

node scripts/update-test-ouput.js -repository relative/path/to/the/repository

It will then be output inside test-samples/repository-name.

To check the stability of the reformating, you can run several times Prettier with the -times flag (e.g. 5 times):

node scripts/update-test-output.js -single -times 5

If you run:

node scripts/update-test-ouput.js

It will simply update all the tests located in test/unit-test folder.

If you would like to run all the prettier-java-plugin tests, simple use the following command:

yarn test

Formatting

The prettier-java source code is (unsurprisingly) formatted using prettier. Make sure to properly format the source code before committing by running:

yarn run format:fix

Unit Testing

All Unit tests in this project are implemented with the Mocha testing framework and the Chai assertion library.