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How can i test an observable that has pipe and map?

I'm assigning values to this variables inside ngOnInit:
this.simStatsList$ = this.sideMenuService.getSimStatsList();
this.currentStation$ = this.simStatsList$.pipe(
map(station => station.find((station: ISimStats) => station.stationName === this.authService.userStation)),
) as Observable<ISimStats>;
This is my test:
it('should select userStation as currentStation', () => {
component.currentStation$.subscribe((response) => {
expect(response).toEqual(
{ stationName: 'test', stats: { open: 0, down: 0, preflight: 0 } }
);
});
});
It passes but is not covering the map function from rxjs. Also im providing sideMenuService and AuthService as mocked values and this is my mock. I'm missing something but i don't know what is it.
export const mockSideMenuService = {
getSimStatsList: () =>
of([
{ stationName: 'test', stats: { open: 0, down: 0, preflight: 0 } },
{ stationName: 'test1', stats: { open: 1, down: 1, preflight: 1 } }
] as ISimStats[])
}
export const mockAuthService = {
userStation: 'test'
}
Could you help me to cover the whole code?

After #will alexander comment i did some change and it worked:
First, pass the function to the sideMenuService and recieve needed data as parameters:
side-menu.service.ts
getCurrentSimStats(
simStatsList$: Observable<ISimStats[]>,
currentStation: string): Observable<ISimStats> {
return simStatsList$.pipe(
map((station) => station.find((station: ISimStats) => station.stationName === currentStation))) as Observable<ISimStats>;
}
Then my component test coverage passed as 100% but the sideMenuService wasn't so i wrote this small test on service spec file:
side-menu.service.spec.ts
it('should getCurrentStation', () =>{
service.getCurrentSimStats(of(mockSideMenuService.mockSimStatsResponse), 'test').subscribe((res) => {
expect(res).toEqual(mockSideMenuService.mockCurrentSimStatsResponse);
});
})
After this, everything worked and tests are passing!

How to initialize variables referencing each other?

I'm using TypeScript with validate-value which uses ajv under the hood. I want to create validation schemas for filters similiar to MongoDB operators.
Each schema should have its own file but since it's possible to nest one filter into another I'm creating a circular reference before initializing the schemas. So I'm getting the error
ReferenceError: Cannot access 'filterSchema' before initialization
How to reproduce the problem with plain Node and JS:
package.json
{
"type": "module",
"scripts": {
"dev": "node main.js"
}
}
main.js
import { filterSchema } from "./filterSchemas/filterSchema.js";
console.log(filterSchema);
.filterSchemas/filterSchema.js
import { logicalOperatorSchema } from "./logicalOperatorSchema.js";
const filterSchema = {
type: "object",
oneOf: [logicalOperatorSchema],
};
export { filterSchema };
.filterSchemas/logicalOperatorSchema.js
import { notSchema } from "./notSchema.js";
const logicalOperatorSchema = {
type: "object",
oneOf: [notSchema],
};
export { logicalOperatorSchema };
.filterSchemas/notSchema.js
import { filterSchema } from "./filterSchema.js";
const notSchema = {
type: "object",
properties: {
$not: filterSchema,
},
required: ["$not"],
additionalProperties: false,
};
export { notSchema };
Do you have any suggestions how to solve this problem?
I also tried to put all schemas into a single file but that didn't solve the actual problem.
schemas.js
const notSchema = {
type: "object",
properties: {
$not: filterSchema,
},
required: ["$not"],
additionalProperties: false,
};
const logicalOperatorSchema = {
type: "object",
oneOf: [notSchema],
};
const filterSchema = {
type: "object",
oneOf: [logicalOperatorSchema],
};
export { filterSchema }
And I also do think that solving this problem solves the other one
const foo = {
x: bar
};
const bar = {
y: foo
};
console.log(foo);

You can do it like this, but it is not going to be useful.
var foo = {
x: bar
}
var bar = {
y: foo
}
foo.x = bar
bar.y = foo
console.log(foo)
console.log(foo.x.y.x.y)

Using XState, how can I access name of current state in an action?

I'm playing around learning XState and wanted to include an action in a machine that would just log the current state to console.
Defining a simple example machine like so, how would I go about this? Also note the questions in the comments in the code.
import { createMachine, interpret } from "xstate"
const sm = createMachine({
initial: 'foo',
states: {
foo: {
entry: 'logState', // Can I only reference an action by string?
// Or can I add arguments here somehow?
on: {
TOGGLE: {target: 'bar'}
}
},
bar: {
entry: 'logState',
on: {
TOGGLE: {target: 'foo'}
}
}
}
},
{
actions: {
logState(/* What arguments can go here? */) => {
// What do I do here?
}
}
});
I know that actions are called with context and event as arguments but I don't see a way to get the current state from either of those. Am I missing something here?

For a simple use case like yours, you could try recording the state on transition.
let currentState;
const service = interpret(machine).onTransition(state => {
if (state.value != currentState) {
// TODO: terminate timer if any and start a new one
currentState = state.value;
}
});
Then use the value in your actions.
See more here: https://github.com/statelyai/xstate/discussions/1294

Actions receive three arguments - context, event and meta. meta have property state, which is current state.
import { createMachine } from "xstate";
let metaDemo = createMachine(
{
id: "meta-demo",
initial: "ping",
states: {
ping: {
entry: ["logStateValues"],
after: { TIMEOUT: "pong" },
},
pong: {
entry: ["logStateValues"],
after: { TIMEOUT: "ping" },
},
},
},
{
delays: {
TIMEOUT: 3000,
},
actions: {
logStateValues(ctx, event, meta) {
if (meta.state.matches("ping")) {
console.log("It's PING!");
} else if (meta.state.matches("pong")) {
console.log("And now it's PONG");
} else {
console.log(
`This is not supposed to happen. State is: ${meta.state
.toStrings()
.join(".")}`
);
}
},
},
}
);

config error : Invalid value undefined for HardhatConfig.networks.paths.url

this is my hardhat.config.js file code :
require("#nomiclabs/hardhat-waffle");
// This is a sample Hardhat task. To learn how to create your own go to
// https://hardhat.org/guides/create-task.html
task("accounts", "Prints the list of accounts", async (taskArgs, hre) => {
const accounts = await hre.ethers.getSigners();
for (const account of accounts) {
console.log(account.address);
}
});
// You need to export an object to set up your config
// Go to https://hardhat.org/config/ to learn more
/**
* #type import('hardhat/config').HardhatUserConfig
*/
module.exports = {
solidity: "0.8.4",
networks : {
hardhat :{
chainId: 1337,
},
paths :{
artifacts: "./src/artifacts",
},
},
};
and when i compile this using npx hardhat compile
it shows following error :
Error HH8: There's one or more errors in your config file:
Invalid value undefined for HardhatConfig.networks.paths.url - Expected a value of type
string.
To learn more about Hardhat's configuration, please go to https://hardhat.org/config
for your reference i am following this tutorial for building this web3 project : "https://blog.suhailkakar.com/setup-and-build-your-first-web-3-application"

You have to close the network's bracket after the hardhat chain Id :)
Please replace your module.exports object with this
module.exports = {
solidity: "0.8.4",
networks:{
hardhat:{
chainId: 1337,
}
},
paths:{
artifacts: "./src/artifacts"
}
};
P.S: Thanks for pointing this out, I have also updated my article

Required dotenv before using process.env values in hardhat.config.js
require("#nomicfoundation/hardhat-toolbox")
require("dotenv").config()
const RINKEBY_RPC_URL = process.env.RINKEBY_RPC_URL
const PRIVATE_KEY = process.env.PRIVATE_KEY
const PRIVATE_KEY_USER1 = process.env.PRIVATE_KEY_USER1
/** #type import('hardhat/config').HardhatUserConfig */
module.exports = {
defaultNetwork: "hardhat",
solidity: {
compilers: [
{ version: "0.8.8" },
{ version: "0.6.6" },
{ version: "0.8.16" },
],
},
networks: {
rinkeby: {
url: RINKEBY_RPC_URL,
accounts: [PRIVATE_KEY, PRIVATE_KEY_USER1],
chainId: 4,
},
},
}

How to overcome jest "Cannot access before initialization" problem?

settings.js
export default {
web: {
a: 1
},
mobile: {
b: 2
}
};
getSetting.js
import settings from "./settings";
export const getSetting = platform => {
return settings[platform];
};
getSettings.test.js
import { getSetting } from "./getSetting";
const TEST_SETTINGS = { c: 3 };
jest.mock("./settings", () => {
return {
test: TEST_SETTINGS
};
});
test("getSetting", () => {
expect(getSetting("test")).toEqual(TEST_SETTINGS);
});
Error
ReferenceError: Cannot access 'TEST_SETTINGS' before initialization
I believe this has something to do with hoisting. Is there a way to overcome this issue? Does jest provide any other means to achieve this?
I don't want to do this. This is not good when the mock data is large and used in multiple tests.
jest.mock("./settings", () => {
return {
test: { c: 3 }
};
});
expect(getSetting("test")).toEqual({ c: 3 });

jest.mock is automatically hoisted, this results in evaluating mocked module before TEST_SETTINGS is declared.
Also, this results in ./settings being mocked with test named export, while it's expected to have default export.
It shouldn't use temporary variable, the value is available when it's being imported:
import settings from "./settings";
jest.mock("./settings", () => {
return { default: {
test: { c: 3 }
} };
});
...
expect(getSetting("test")).toBe(settings.test);

Or, use Dynamic Imports import().
E.g.
const TEST_SETTINGS = { c: 3 };
jest.mock('./settings', () => {
return {
test: TEST_SETTINGS,
};
});
test('getSetting', async () => {
const { getSetting } = await import('./getSetting');
expect(getSetting('test')).toEqual(TEST_SETTINGS);
});
test result:
PASS examples/61843762/getSettings.test.js
✓ getSetting (4 ms)
Test Suites: 1 passed, 1 total
Tests: 1 passed, 1 total
Snapshots: 0 total
Time: 3.25 s, estimated 4 s
jestjs version: "jest": "^26.6.3"