#getFlowTransformRules

A helper function that generates module.rules configuration for handling Flow type annotations in JavaScript files. The rules use @callstack/repack/flow-loader to remove Flow types from the code before other processing.

#Parameters

interface GetFlowTransformRulesOptions {
  include?: string[];
  exclude?: string[];
  all?: boolean;
  ignoreUninitializedFields?: boolean;
  removeEmptyImports?: boolean;
}

#options

• Required: false

Configuration options for Flow transformations

#options.include

• Type: string[]
• Default: predefined set of React Native libraries that use Flow

Array of module names to include for Flow transformation.

{
  include: [
    // Include specific package
    "react-native",
    "react-native-vector-icons",
    // Include all packages from a scope
    "@react-native",
  ];
}

#options.exclude

• Type: string[]
• Default: []

Array of module names to exclude from Flow transformation.

{
  exclude: [
    // Exclude specific package
    "react-native-vector-icons",
    // Exclude all packages from a scope
    "@react-native-community",
  ];
}

#options.all

• Type: boolean
• Default: true

Whether to bypass looking for @flow pragma comment before parsing

#options.ignoreUninitializedFields

• Type: boolean

Whether to remove uninitialized class fields completely rather than only removing the type (defaults to false)

#options.removeEmptyImports

• Type: boolean
• Default: true

Whether to remove empty import statements which were only used for importing flow types (defaults to true)

#Example

const Repack = require("@callstack/repack");

module.exports = {
  module: {
    rules: [
      ...Repack.getFlowTransformRules({
        include: ["react-native", "@react-native"],
        all: true,
        ignoreUninitializedFields: false,
        removeEmptyImports: true,
      }),
    ],
  },
};