Type 'WebStream<string>' is not assignable to type 'string'.

[thapecroth]

Got the following error when running

tsc --noEmit

node_modules/openpgp/openpgp.d.ts:10:85 - error TS2307: Cannot find module '@openpgp/web-stream-tools' or its corresponding type declarations.

10 import type { WebStream as GenericWebStream, NodeStream as GenericNodeStream } from '@openpgp/web-stream-tools';
                                                                                       ~~~~~~~~~~~~~~~~~~~~~~~~~~~

src/utils/utils.ts:11:3 - error TS2322: Type 'WebStream<string>' is not assignable to type 'string'.

On openpgp version 5.3.0

I believe this is cause by the fact that in the package.json, it listed as devdependency instead of dependency !?

[thapecroth]

Turn out I can just fixed it by install opengpp 5.3.1.

[srn271]

I get the same error when upgrading from 5.10 to >=5.2.0 && <= 5.5.0.

The error is probably due to the changes in this commit:
d89cc48

const encrypted: string = await openpgp.encrypt({
  message, // openpgp.Message<string>
  encryptionKeys, // openpgp.PublicKey[]
  signingKeys // openpgp.PrivateKey[]
})

[srn271]

Nevermind. Installing the latest version of @openpgp/web-stream-tools (0.0.11) into devDependencies fixes the issue.

Should be mentioned in the documentation or even in the release notes, as already addressed in #1502 (comment).

[rene-leanix]

Having to install an additional package like @openpgp/web-stream-tools to fix the typing isn't a great solution, of course, but it also doesn't seem to work any more either.

The reason it doesn't work is that @openpgp/web-stream-tools does not export the interface NodeStream (any more?), which is why TypeScript treats it as any, with the result that the conditional T extends NodeStream<infer X> is always evaluated as true, so the resulting type is NodeStream<string>, even if T is string. In other words, the return type of openpgp.encrypt<string>() is Promise<NodeStream<string>> and not Promise<string>.

This can be fixed by changing

export function encrypt<T extends MaybeStream<Data>>(options: EncryptOptions & { message: Message<T>, format?: 'armored' }): Promise<
  T extends WebStream<infer X> ? WebStream<string> :
  T extends NodeStream<infer X> ? NodeStream<string> :
  string
>;

to

export function encrypt<T extends MaybeStream<Data>>(options: EncryptOptions & { message: Message<T>, format?: 'armored' }): Promise<
  T extends ReadableStream<unknown> ? (
    T extends WebStream<unknown> ? WebStream<string> :
    T extends NodeStream<unknown> ? NodeStream<string> :
    string
  ) : string
>;

As this check is done in several places, it may be good to define a new generic type of it, e.g.:

type StreamOrSimple<MessageType, SimpleReturnType> = MessageType extends ReadableStream<unknown> ? (
  MessageType extends WebStream<unknown> ? WebStream<SimpleReturnType> :
  MessageType extends NodeStream<unknown> ? NodeStream<SimpleReturnType> :
  SimpleReturnType
) : SimpleReturnType;

export function encrypt<T extends MaybeStream<Data>>(options: EncryptOptions & { message: Message<T>, format?: 'armored' }): Promise<StreamOrSimple<T, string>>;
export function encrypt<T extends MaybeStream<Data>>(options: EncryptOptions & { message: Message<T>, format: 'binary' }): Promise<StreamOrSimple<T, Uint8Array>>;
export function encrypt<T extends MaybeStream<Data>>(options: EncryptOptions & { message: Message<T>, format: 'object' }): Promise<Message<T>>;

Should I create a PR along those lines, @larabr?

[larabr]

@rene-leanix please see this: #1720 (comment) , it should resolve TS issues with v5.

[rene-leanix]

@larabr, yes, installing @openpgp/web-stream-tools@0.0.11-patch-0 also fixes the issue, as it still contains a definition of NodeStream. Thanks! I missed that issue.

It should still be preferable to adjust the typing to avoid the need to install @openpgp/web-stream-tools.