jscodeshift codemod to add angular import statement

angular-import-codemod.js

module.exports = function (file, api) {
    const j = api.jscodeshift;
    const ast = j(file.source);
    const body = ast.find(j.Program).get('body');

    // Find each angular.<method>() usage
    var angularUsages = ast.find(j.MemberExpression, isAngularExpression);

    if (angularUsages.length === 0) {
        return null;
    }

    // import angular from 'angular'
    const angularImport = ast.find(j.ImportDeclaration, isAngularImport);

    if (angularImport.length) {
        return null;
    }

    ast // remove 'use strict'
        .find(j.ExpressionStatement, isUseStrictExpression)
        .forEach((ast) => j(ast).remove());

    body.get(0).insertBefore(getImport(j));

    // Restore opening comments/position
    body.value[0].comments = body.value[1].comments;
    delete body.value[1].comments;

    return ast.toSource({
        arrowParensAlways: true,
        quote: 'single',
    });
};

function isUseStrictExpression(node) {
    return (
        node.type === 'ExpressionStatement' &&
        node.expression &&
        node.expression.value === 'use strict'
    );
}

function isAngularExpression(node) {
    return (
        node.type === 'MemberExpression' &&
        node.object.name === 'angular'
    );
}

function isAngularImport(node) {
    return (
        node.type === 'ImportDeclaration' &&
        node.source.value === 'angular'
    );
}

function getImport(j) {
    return j.importDeclaration([j.importDefaultSpecifier(j.identifier('angular'))], j.literal('angular'));
}