babel-plugin-typescript-to-proptypes/src/addToFunctionOrVar.ts

Generate React PropTypes from TypeScript prop interfaces.

import { types as t } from '@babel/core';
import { convertToPropTypes } from './convertBabelToPropTypes';
import { extractGenericTypeNames } from './extractGenericTypeNames';
import { createPropTypesObject, mergePropTypes } from './propTypes';
import { ConvertState, Path, PropTypeDeclaration } from './types';

function findStaticProperty(
	path: Path<t.Node>,
	funcName: string,
	name: string,
): t.AssignmentExpression | undefined {
	const expr = path.getAllNextSiblings().find(
		(sibPath) =>
			t.isExpressionStatement(sibPath.node) &&
			t.isAssignmentExpression(sibPath.node.expression, { operator: '=' }) &&
			t.isMemberExpression(sibPath.node.expression.left) &&
			t.isObjectExpression(sibPath.node.expression.right) &&
			t.isIdentifier(sibPath.node.expression.left.object, {
				name: funcName,
			}) &&
			t.isIdentifier(sibPath.node.expression.left.property, { name }),
	);

	// @ts-expect-error Allow unknown access
	return expr?.node.expression as t.AssignmentExpression;
}

export function addToFunctionOrVar(
	path: Path<t.FunctionDeclaration | t.VariableDeclaration>,
	name: string,
	propsType: PropTypeDeclaration,
	state: ConvertState,
) {
	const rootPath =
		t.isExportNamedDeclaration(path.parent) || t.isExportDefaultDeclaration(path.parent)
			? path.parentPath
			: path;
	const defaultProps = findStaticProperty(rootPath, name, 'defaultProps');
	const defaultPropsKeyList: string[] = [];

	if (
		defaultProps &&
		t.isAssignmentExpression(defaultProps) &&
		t.isObjectExpression(defaultProps.right)
	) {
		defaultProps.right.properties.forEach((prop) => {
			if (t.isProperty(prop) && t.isIdentifier(prop.key)) {
				defaultPropsKeyList.push(prop.key.name);
			}
		});
	}

	const typeNames = extractGenericTypeNames(propsType);
	const propTypesList = convertToPropTypes(
		state.componentTypes,
		typeNames,
		state,
		defaultPropsKeyList,
	);

	if (typeNames.length === 0 || propTypesList.length === 0) {
		return;
	}

	const propTypes = findStaticProperty(rootPath, name, 'propTypes');

	if (propTypes) {
		propTypes.right = mergePropTypes(propTypes.right, propTypesList, state)!;
	} else {
		rootPath.insertAfter(
			t.expressionStatement(
				t.assignmentExpression(
					'=',
					t.memberExpression(t.identifier(name), t.identifier('propTypes')),
					createPropTypesObject(propTypesList, state),
				),
			),
		);
	}
}