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How to add 'await' at node using jscodeshift?

I recently have spotted jscodeshift and leveraging it for refactoring.
But I can't find a way to add await before the node that I am seeking.
// AS-IS
userEvent.click(a);
await userEvent.click(b);
// TO-BE
await userEvent.click(a);
await userEvent.click(b);
This is how I query userEvent.click
const getFunctionCall = (obj:string, prop:string) => {
return source.find(j.CallExpression, {
callee: {
type: 'MemberExpression',
object: {
name: obj
},
property: {
name:prop
}
}
})
}
const clicks = getFunctionCall('userEvent', 'click');
clicks.forEach(i=> {
if (i.parentPath.value.type !== 'AwaitExpression') {
// code goes here
}
})
How can I add await before userEvent and let the rest code stay same in this case?
I checked out the document to find out how to build a statement or expression, but it wasn't understandable for me as I've just started to use this. I would appreciate if you can introduce any good materials for this library.
Thanks in advance!

It is simple, you need to wrap the existing CallExpression inside an await expression like this:
// Press ctrl+space for code completion
export default function transformer(file, api) {
const j = api.jscodeshift;
const root = j(file.source);
const body = root.get().value.program.body;
root.find(j.CallExpression, {
callee: {
object: {
name: "userEvent"
},
property: {
name: "click"
}
}
}).filter(path => {
return path.value.arguments[0].name === "a" ;
}).replaceWith(path => {
return j.awaitExpression(path.value)
});
return root.toSource();
}

Exported function to pass arguments and a constant to another function

I don't really know how to describe this, but I'll try explain it.
I want to be able to call func1() and func2(), but going through handler() in a module.
I want it in a way where calling module.exported1("foo") will call handler(func1, "foo"), in turn calling func1("foo"). The issue I'm having is that if I export 'exported1' as handler(func1), I can't pass any arguments exported1 was called with (As far as I know). Is there a workaround for this?
NOTE: It is a module, and I need it to be exported without the user needing to provide func1 and func2 to handler().
function func1(args) {
...
}
function func2(args) {
...
}
function handler(func, args) {
return func()
}
module.exports = {
exported1 = handler(func1, ...),
exported2 = handler(func2, ...)
}

Not sure I get why to use this pattern, but I am sure there is more to the code and guess you could do the following:
function func1(args) {
console.info(`func1 ${args}`);
}
function func2(args) {
console.info(`func2 ${args}`);
}
function handler(func, args) {
return func(args);
}
module.exports = {
exported1: (args) => {
return handler(func1, (args));
},
exported2: (args) => {
return handler(func2, (args));
},
};

You just need to export the function:
module.exports = {
exported = handler
}
Or, just:
exports.exported = handler
Now, after import, you can call with parameters:
exported(func1,...)
exported(func2,...)
After reading your edited question, I think you want to do something like this but I'm not pretty sure:
function handler(func) {
// you can replace it with function(args) { instead of arrow function
return (args) => {
return func(args)
}
}
module.exports = {
exported1 = handler(func1),
exported2 = handler(func2)
}
exported1(args)

Need a custom assignment implementaion

I am working with some state management application where I have a data structure as follows
const mainObject = {
firstLevel: {
secondLevel: {
thirdLevel: {
actualProperty: 'Secret'
}
}
},
firstLevelUntouched:{
secondLevelUntouched:{
thirdLevelUntouched:{
untouchedProperty:'I don`t want to change'
}
}
}
};
I want to change the actualProperty to a new value which out a deepClone
I did it with the following code
const modified = {
...mainObject,
...{
firstLevel: {
...mainObject.firstLevel,
...{
secondLevel: {
...mainObject.firstLevel.secondLevel,
thirdLevel: {
...mainObject.firstLevel.secondLevel.thirdLevel,
actualProperty: 'New secret'
}
}
}
}
}
}
But its looks like Bulky Code. So I need to write a function like
modified = myCustomAssignment(mainObject, ['firstLevel', 'secondLevel', 'thirdLevel', 'actualProperty'], 'New secret')
Can anyone help me on this?

You could use a simple traversal function for this that just traverses the passed properties until it arrives as the final one, then sets that to the new value.
function myCustomAssignment(mainObject, propertyList, newValue) {
const lastProp = propertyList.pop();
const propertyTree = propertyList.reduce((obj, prop) => obj[prop], mainObject);
propertyTree[lastProp] = newValue;
}
You could even add propertyList = propertyList.split('.') to the top of this function so the list can be passed in as an easy-to-read string, like myCustomAssignment(mainObject, 'firstLevel.secondLevel.thirdLevel.actualProperty', 'new value') if you wanted that.

export function mutateState(mainObject: object, propertyList: string[], newValue: any) {
const lastProp = propertyList.pop();
const newState: object = { ...mainObject };
const propertyTree =
propertyList
.reduce((obj, prop) => {
obj[prop] = { ...newState[prop], ...obj[prop] };
return obj[prop];
}, newState);
propertyTree[lastProp] = newValue;
return newState as unknown;
}
This fixed my issue. thanks all..

javascript create dynamic class by object

Task: I want to create a dynamic class by a given JSON Object in ES6.
After a lot of reading in the MDN web docs and much stackoverflow questions i'm totally confused how to get this work.
JSON Object
{
constructor: {
name: "someName",
},
getter: {
function1: () => "someOutput",
function2: () => false,
}
}
While I tried to solve the problem I figured out how to create dynamic getter methods by using "Proxy" or "defineProperty" but how i should handle the constructor?? :(
I hope someone can help me with a hint or an example.
Thanks in advance

You can add constructor to your class created by Proxy using Proxy's "construct" handler method:
const jsonObj = {
constructor: {
name: "someName",
},
getter: {
function1: () => "someOutput",
function2: () => false,
}
}
function baseClass(obj) {
for(i in obj){
this[i] = obj[i]
}
}
const handler = {
construct(target, args) {
return new target(jsonObj.constructor);
}
};
const NewClass = new Proxy(baseClass, handler);

Usage of Javascript syntax : method(param1,param2,(something)=>{//some code},param4);

This method syntax seems to be little strange.
Here is the method declaration. Some normal javascript method implementation.
sendHttpRequest: function (aUri, aUploadData, aContentType, aExisting, aSetupChannelFunc, aFailureFunc, aUseStreamLoader = true) {
//method implementation
}
This is the actual usage. There what does mean by using ()=>{//some statements} as a parameter?
function someFunction(){
this.calendar.sendHttpRequest(requestUri, queryXml, MIME_TEXT_XML, null, (channel) => {
//some statements
return this;
}, () => {
if (this.setA && this.setB) {
//some statements
}
}, false);
//someFunction's statements
}