@quintoandar/farewell-immutablejs

Farewell ImmutableJS

Codemods to migrate Immutable.js to ES6.

Never heard of codemods? Here is a quick summary from facebook/codemod:

codemod is a tool/library to assist you with large-scale codebase refactors that can be partially automated but still require human oversight and occasional intervention.

How to use

# installing globally
npm install -g @quintoandar/farewell-immutablejs
@quintoandar/farewell-immutablejs

# or using npx
npx @quintoandar/farewell-immutablejs

Use the --help flag or refer to the help file.

Features

Drop immutable import

- import { fromJS } from 'immutable';

Remove .fromJS()

- const a = fromJS({ value: 1 });
+ const a = { value: 1 };

Remove .toJS()

- const js = state.toJS();
+ const js = state;

Replace .get()

// without default value
- const a = state.get('value');
+ const a = state?.value;

// with default value
- const a = state.get('value', 10);
+ const a = state?.value ?? 10;

// recursive gets are ignored
// for cases like this, run twice
{
- value: state.get('a').get('b'),
+ value: state.get('a')?.b,
}

Replace .getIn()

// without default value
- const a = state.getIn(['b', 'c']);
+ const a = state?.b?.c;

// with default value
- const a = state.getIn(['b', 'c'], 10);
+ const a = state?.b?.c ?? 10;

Replace .set()

// with a literal key
- state.set('a', 10);
+ state.a = 10;

// with a variable key
- state.set(key, 10);
+ state[key] = 10;

Replace .setIn()

- state.setIn(['a', 'b', c, 'd'], 10);
+ state.a.b.c.d = 10;

Replace .merge()

- const newState = state.merge({ a: 10 });
+ const newState = { ...state, a: 10 };

Unsupported methods

The methods below have either small cost-benefit to implement a codemod or are too difficult to implement given name collisions.

• contains
• includes
• some
• find
• withMutations
• removeIn
• sortBy
• remove
• first
• last
• add
• mergeIn
• mergeDeep
• update
• updateIn
• map
• filter
• reduce