TypeScript error on update method: TS2349: Cannot invoke an expression whose type lacks a call signature. Type 'typeof "/immutability-helper/index"' has no compatible call signatures.

[ajalgaonkar]

I am currently getting the following issue:
TS2349: Cannot invoke an expression whose type lacks a call signature. Type 'typeof "~/node_modules/immutability-helper/index"' has no compatible call signatures.

This issue does not happen on the 2.6.4 version but as soon as the solution pulled in the 2.6.5 version i started getting this issue.
For now I have made the version constant at 2.6.4, but wanted to notify you about this issue.

Thanks.

[andreiglingeanu]

Thanks. Could you please post a code snippet so that we can reproduce the problem?

[chitswe]

@ajalgaonkar You need to change import statement. Use import update from "immutability-helper"; instead of import * as update from "immutability-helper". Because typescript type declaration file has been changed in 2.6.5.

[andreiglingeanu]

I believe yes, we did this change. I think it's better to just have a default export & everyone should be using import update from "immutability-helper";

[DavidHall]

I have hit the same problem with the typescript definition change in 2.6.5, and although changing my import from import * as update from "immutability-helper" to import update from "immutability-helper" does resolve the compiler error, I now hit run time errors.

The run time error I see is:

TypeError: immutability_helper_1.default is not a function

And that is just from a standard call like:

const newData = update(myData, {
    x: {y: {z: {$set: 7}}},
    a: {b: {$push: [9]}}
});

It could be that the problem is somewhere in my webpack setup, with that not correctly identifying the default export as a function.

One work around that I found is to call the newContext() function to create a new function that does work:

import { newContext } from "immutability-helper";
const update = newContext();

[chitswe]

@DavidHall I also have the same problem like you with new version. I thought it could be the problem with webpack configuration. So I didn't report it here.

[andreiglingeanu]

Oh, this sounds bad, I guess it's because we have declared the update function as a default ES6 export in typings & in the actual source code we have a common JS export module.exports = newContext().

I guess we'll need the typings to fix the library code to get it working, at least because the README says that an ES6 default import is a valid way of consuming the lib: import update from 'immutability-helper';

[vvolodin]

any workaround for this? having runtime errors too. importing {newContext} does not compile for me.

update: my solution to this was using the older * as syntax and casting it to any after importing...

[atfzl]

@andreiglingeanu instead of:

module.exports = newContext();
module.exports.newContext = newContext;

we should change it to:

module.exports = newContext();
module.exports.default = newContext();
module.exports.newContext = newContext;

It is working after adding default export here.

[andreiglingeanu]

It seems like that is the way to go, a bit hacky though...

I opened a PR for that, please try it

[ob-ivan]

For those who are like me:

find src -name '*.tsx' | xargs sed -i 's/import \* as update from "immutability-helper";/import update from "immutability-helper";/'

[bhagyas]

Issue continues to exist on 2.7.0. Downgrading the dependency version to 2.6.4 seems to work.