PHP (Phan) support for lsp-mode using phan/phan.

This is forked from emacs-lsp/lsp-php. (The way to determine the root Phan namespace is different)

1. Enhanced error detection from Phan
2. “Go To Definition” support.

Clone this repository, emacs-lsp/lsp-mode, and emacs-lsp/lsp-ui to suitable paths. Then add the following settings to your Emacs configuration.
(TODO: If you also wish to install lsp-php for other features such as autocomplete, are multiple language servers for the same language supported?)

(add-to-list 'load-path "/path/to/lsp-phan/")
;*******************************************************************************
; NOTE: This is incompatible with lsp-php
; lsp-mode does not support multiple clients per major mode, yet
; See https://github.com/emacs-lsp/lsp-mode/issues/105
;*******************************************************************************

; TODO: Make this more convenient. The below command should be fine
; "php" may need be replaced with a php 7.0 installation, preferably with php-ast installed.
; TODO: Document the individual settings that were added to lsp-phan with M-x customize
(defvar lsp-phan-language-server-command
  (list
	"php"
	"/path/to/phan_stable/phan"
	"--language-server-allow-missing-pcntl"
	"--allow-polyfill-parser"
	"--use-fallback-parser"
	"--memory-limit" "1G"
	"--language-server-enable-go-to-definition"
	"--project-root-directory" "/path/to/analyzed_project"
	"--language-server-on-stdin"))

; For php-language-server
(require 'flycheck)

; Can't be used at the same time as (require 'lsp-php), see above
(require 'lsp-phan)

(require 'php-mode)
(require 'lsp-mode)

(require 'lsp-ui)
(add-hook 'lsp-mode-hook 'lsp-ui-mode)
(add-hook 'php-mode-hook 'flycheck-mode)
(add-hook 'php-mode-hook 'lsp-mode)

(add-hook 'php-mode-hook #'lsp-phan-enable)

You will need to install phan/phan.

You will also need to set up the project with a .phan/config.php if you have not done so already.

Before installing php-language-server, make sure your ~/.config/composer/composer.json includes the lines below. The settings apply to all globally installed Composer packages, so proceed with caution. If you do not want to edit your global Composer configuration, see the section for local installation below.

{
    "minimum-stability": "dev",
    "prefer-stable": true
}

After editing your composer.json, you can install phan/phan.

composer global require phan/phan

• List Errors (C-c ! l)
• Go to definition (M .)

TODO: Make the configuration easier to work with and understand.
See the VS Code extension’s configuration settings.

This package is licensed under the GPLv3 license. For more information, see LICENSE.

It takes about 4-5 days for leetcode to update the contest ratings of participants. So you have to wait for a long time to know your rating changes. This application predicts accurate leetcode rating changes for all the contestants within a few minutes of completion of the contest.

This project consists of two types of user interfaces. You can either use browser extension or the website to get your rating changes.

You can install the extension from Chrome Web Store. It adds the rating changes on leetcode ranking pages itself.

You can also visit lcpredictor.onrender.com to get your rating changes.

This project is written in Node + MongoDB + Redis tech stack. We can divide it into three microservices.

It is the most important part of the project. It’s job is to fetch the data from leetcode and predict the contest ratings periodically.

Rating prediction is a cpu intensive task. Therefore a nodejs C++ addon is implemented for this task so that we can utilize threading with better performance using C++. For performance measurement we got these results :

It implements leetcode’s latest rating prediction algorithm. Rating predictions are very close to the original rating but the accuracy may not be 100% due to changes in contest rankings after the completion of contest (leetcode rejudges some submissons).

These are the results for the predictions of weekly-contest-242:

Job scheduling is required for processing jobs on desired time. Leetcode contests are weekly and biweekly. We can schedule them by scheduling a repeated job. But for making it more generic, job schedulers are implemented who schedules prediction and data update jobs. These job schedulers are scheduled as a repeated job. It is accomplished by using bull, a redis based queue for Node. A bull dashboard is also integrated using bull-board.

It is built using express framework. Ejs is used for writing templates. It contains a table for contests and ranking pages with predicted rating changes for all the contests. Pagination is added to ranking pages for better user experience and performace.

It is also implemented using express framework. It contains an endpoint for fetching users’ predicted rating changes which is used in the browser extension.

IP based rate limit is enforced for both the API and the website using express-rate-limit.

• Clone the repository

  git clone https://github.com/SysSn13/leetcode-rating-predictor

• Install the dependencies

  npm install

• Setup environment variables

  cp .env.example .env

  Fill in the required values in the .env file.

• Build the predict-addon (if you are using different node version)

  npm run buildAddon

• Start the project

  npm start

• Or start the development server by:

  npm run dev

DATABASE_URL: Connection string for mongodb.

# for web
WEB: Whether to run the website or not. (0 or 1)

RATE_LIMIT_WINDOW: Window size for rate limit in milliseconds (default: 10000).

RATE_LIMIT: Number of requests allowed in the window (default: 50).


# for api
API_DISABLED: Whether to disable the API or not. (0 or 1)

API_RATE_LIMIT_WINDOW: Window size for API rate limit in milliseconds (default: 10000).

API_RATE_LIMIT: Number of API requests allowed in the window (default: 20).


# for background
BACKGROUND: Whether to run the background or not. (0 or 1)

REDIS_URL: Connection string for redis.

THREAD_CNT: Number of threads for prediction.(default: 4)

# bull-board auth
BULLBOARD_USERNAME: username for bull-board login

BULLBOARD_PASS: password for bull-board login

SESSION_SECRET: secret to hash the session

Current only chrome browser is supported. It uses manifest V3. See this for getting started with extension development. Source code for the extension is in ./chrome-extension.

You can contribute by creating issues, feature/ pull requests. Any meaningful contributions you make are greatly appreciated.

For contributing in the source code, please follow these steps:

• Fork the Project
• Create your new Branch

  git checkout -b feature/AmazingFeature

• Commit your Changes

  git commit -m 'Add some AmazingFeature'
  

• Push to the Branch

  git push origin feature/AmazingFeature
  

• Open a Pull Request

Distributed under the MIT License. See LICENSE for more information.

Generic & Typesafe Vector/List implementation in C (~150 LOC).

Vector/List is fundamental data structure for just about anything. Almost all programming languages as a builtin or packaged into standard library except for C. Also, it includes Iterator for free which allows you to do pretty interesting stuff such as peek, next, done, etc.

Go to cvector.h for complete list of APIs.

It has a single header file called cvector.h. You can simply copy/paste in your source directory to get started. You can also install via clib (package manager for C).

With clib:

clib install robusgauli/cvector

#include "cvector.h"

int main() {
  // Define type that holds vector of int
  CVector(int) vector_int_t;

  // Declare variable of type `vector_int_t`
  vector_int_t vector_int;

  // Initialize
  cvector__init(&vector_int);

  // Push number to vector
  for (int i = 0; i < 100; i++) {
    cvector__add(&vector_int, i);
  }

  // Size of the vector
  size_t size = cvector__size(&vector_int);

  // Iterate over elements
  for (int i = 0; i < 100; i++) {
    int number = cvector__index(&vector_int, i);
    printf("Number is: %d\n", number);
  }
}

#include "cvector.h"

// Define zero type of int
CVector(int) vector_int_t;


// Define iterator type for iterator_int_t
CVector_iterator(vector_int_t) iterator_int_t;

int main() {

  // Declare variable of type `zero_int_t`
  vector_int_t vector_int;

  // Initialize
  cvector__init(&vector_int);

  // Push elements to vector
  for (int i = 0; i < 10; i++) {
    cvector__add(&vector_int, i*i);
  }

  // Declare varaible of type `iterator_int_t`
  iterator_int_t iterator_int;

  // Initialize iterator with vector of int
  cvector_iterator__init(&iterator_int, &vector_int);

  // Peek the current element
  int number = cvector_iterator__peek(&iterator_int);
  printf("The peeked number is: %d\n", number);

  // Iterate using iterator
  for (;;) {
    if (cvector_iterator__done(&iterator_int)) {
      break;
    }

    int number = cvector_iterator__next(&iterator_int);
    printf("Got number: %d\n", number);
  }
}

#include "cvector.h"

typedef struct Node_t {
  int x;
  int y;
} Node_t;

int main() {
  // Define vector type of `Node_t`
  CVector(Node_t) vector_node_t;

  // Declare variable of type `vector_node_t`
  vector_node_t vector_node;

  // Initialize vector
  cvector__init(&vector_node);

  // Push to vector
  for (int i = 0; i < 100; i++) {
    Node_t node = ((Node_t){.x = i, .y = i*i});
    cvector__add(&vector_node, node);
  }

  // Define iterator of type `vector_node_t`
  CVector_iterator(vector_node_t) iterator_node_t;

  // Declare variable of type `iterator_node_t`
  iterator_node_t iterator_node;

  // Initialize iterator
  cvector_iterator__init(&iterator_node, &vector_node);

  // Iterate
  for(;;) {
    if (cvector_iterator__done(&iterator_node)) {
      break;
    }

    Node_t node = cvector_iterator__next(&iterator_node);
    printf("Node: x -> %d & y -> %d\n", node.x, node.y);
  }
}

#include <cvector.h>

int main() {
  CVector(int) vector_int_t;
  vector_int_t vector_int;

  cvector__init(&vector_int);

  cvector__add(&vector_int, 12);
  cvector__add(&vector_int, 13);
  cvector__add(&vector_int, 14);
  cvector__add(&vector_int, 15);

  // First
  {
    // Get the first element
    int number = cvector__first(&vector_int);
    printf("First element: %d\n", number);
  }

  // Last
  {
    // Get the last element by reference
    int* number = cvector__last_ref(&vector_int);
    printf("Last element: %d\n", *number);
  }

  // Pop
  {
    size_t size_before = cvector__size(&vector_int);

    printf("Size of vector before pop: %ld\n", size_before);

    // Pop element from the vector
    int number = cvector__pop(&vector_int);

    printf("Popped element: %d\n", number);

    size_t size_after = cvector__size(&vector_int);
    printf("Size of vector after pop: %ld\n", size_after);
  }

  // Set value at index
  {
    if(cvector__set_at_index(&vector_int, 0, 56) == -1) {
      fprintf(stderr, "Failed to set the value '56' at index '0'");
    }
  }
}

Copyright © 2020-20121 Robus, LLC. This source code is licensed under the MIT license found in the [LICENSE.txt] The documentation to the project is licensed under the CC BY-SA 4.0 license.

Made with ♥ by Robus Gauli ([@robusgauli]

Generic & Typesafe Vector/List implementation in C (~150 LOC).

Vector/List is fundamental data structure for just about anything. Almost all programming languages as a builtin or packaged into standard library except for C. Also, it includes Iterator for free which allows you to do pretty interesting stuff such as peek, next, done, etc.

Go to cvector.h for complete list of APIs.

It has a single header file called cvector.h. You can simply copy/paste in your source directory to get started. You can also install via clib (package manager for C).

With clib:

clib install robusgauli/cvector

#include "cvector.h"

int main() {
  // Define type that holds vector of int
  CVector(int) vector_int_t;

  // Declare variable of type `vector_int_t`
  vector_int_t vector_int;

  // Initialize
  cvector__init(&vector_int);

  // Push number to vector
  for (int i = 0; i < 100; i++) {
    cvector__add(&vector_int, i);
  }

  // Size of the vector
  size_t size = cvector__size(&vector_int);

  // Iterate over elements
  for (int i = 0; i < 100; i++) {
    int number = cvector__index(&vector_int, i);
    printf("Number is: %d\n", number);
  }
}

#include "cvector.h"

// Define zero type of int
CVector(int) vector_int_t;


// Define iterator type for iterator_int_t
CVector_iterator(vector_int_t) iterator_int_t;

int main() {

  // Declare variable of type `zero_int_t`
  vector_int_t vector_int;

  // Initialize
  cvector__init(&vector_int);

  // Push elements to vector
  for (int i = 0; i < 10; i++) {
    cvector__add(&vector_int, i*i);
  }

  // Declare varaible of type `iterator_int_t`
  iterator_int_t iterator_int;

  // Initialize iterator with vector of int
  cvector_iterator__init(&iterator_int, &vector_int);

  // Peek the current element
  int number = cvector_iterator__peek(&iterator_int);
  printf("The peeked number is: %d\n", number);

  // Iterate using iterator
  for (;;) {
    if (cvector_iterator__done(&iterator_int)) {
      break;
    }

    int number = cvector_iterator__next(&iterator_int);
    printf("Got number: %d\n", number);
  }
}

#include "cvector.h"

typedef struct Node_t {
  int x;
  int y;
} Node_t;

int main() {
  // Define vector type of `Node_t`
  CVector(Node_t) vector_node_t;

  // Declare variable of type `vector_node_t`
  vector_node_t vector_node;

  // Initialize vector
  cvector__init(&vector_node);

  // Push to vector
  for (int i = 0; i < 100; i++) {
    Node_t node = ((Node_t){.x = i, .y = i*i});
    cvector__add(&vector_node, node);
  }

  // Define iterator of type `vector_node_t`
  CVector_iterator(vector_node_t) iterator_node_t;

  // Declare variable of type `iterator_node_t`
  iterator_node_t iterator_node;

  // Initialize iterator
  cvector_iterator__init(&iterator_node, &vector_node);

  // Iterate
  for(;;) {
    if (cvector_iterator__done(&iterator_node)) {
      break;
    }

    Node_t node = cvector_iterator__next(&iterator_node);
    printf("Node: x -> %d & y -> %d\n", node.x, node.y);
  }
}

#include <cvector.h>

int main() {
  CVector(int) vector_int_t;
  vector_int_t vector_int;

  cvector__init(&vector_int);

  cvector__add(&vector_int, 12);
  cvector__add(&vector_int, 13);
  cvector__add(&vector_int, 14);
  cvector__add(&vector_int, 15);

  // First
  {
    // Get the first element
    int number = cvector__first(&vector_int);
    printf("First element: %d\n", number);
  }

  // Last
  {
    // Get the last element by reference
    int* number = cvector__last_ref(&vector_int);
    printf("Last element: %d\n", *number);
  }

  // Pop
  {
    size_t size_before = cvector__size(&vector_int);

    printf("Size of vector before pop: %ld\n", size_before);

    // Pop element from the vector
    int number = cvector__pop(&vector_int);

    printf("Popped element: %d\n", number);

    size_t size_after = cvector__size(&vector_int);
    printf("Size of vector after pop: %ld\n", size_after);
  }

  // Set value at index
  {
    if(cvector__set_at_index(&vector_int, 0, 56) == -1) {
      fprintf(stderr, "Failed to set the value '56' at index '0'");
    }
  }
}

Copyright © 2020-20121 Robus, LLC. This source code is licensed under the MIT license found in the [LICENSE.txt] The documentation to the project is licensed under the CC BY-SA 4.0 license.

Made with ♥ by Robus Gauli ([@robusgauli]

The wishlists resource allows customers to create a collection of products that they wish they had the money to purchase. A customer might have multiple wishlists so they might want to name them for easy identification.

(urls below do not currently work since we have revoked the ibm cloud membership)

• App         – https://nyu-wishlist-service-f20.us-south.cf.appdomain.cloud
• Dev          – https://nyu-wishlist-service-f20-dev.us-south.cf.appdomain.cloud
• Swagger docs prod – http://nyu-wishlist-service-f20.us-south.cf.appdomain.cloud/apidocs/index.html
• Swagger docs dev   – http://nyu-wishlist-service-f20-dev.us-south.cf.appdomain.cloud/apidocs/index.html

The easiest way to use this lab is with Vagrant and VirtualBox. if you don’t have these software, then the first step is to download and install them.

Download VirtualBox

Download Vagrant

Then all you have to do is to clone this repo and invoke vagrant:

git clone https://github.com/wishlists/wishlists
cd wishlists
vagrant up
vagrant ssh
cd /vagrant

You can run the code to test it out in your browser with the following command:

honcho start

When you are done, you can use Ctrl+C to stop the server and then exit and shut down the vm.

GET /wishlists – Return all the wishlists

GET /wishlists/{wishlist_id} – Return the wishlists with the given id

POST /wishlists – Create a new wishlist record in the database

PUT /wishlists/{wishlist_id} – Update a wishlist record in the database

DELETE /wishlists/{wishlist_id} – Delete a wishlist record in the database

GET /wishlists?name=wishlist_1 – Query the database by the name of the wishlist

GET /wishlists?user_id=1 – Query the database by the user id of the wishlist

PUT /wishlists/{wishlist_id}/disabled – It disables the target wishlist

PUT /wishlists/{wishlist_id}/enabled – It enables the target wishlist

POST /wishlists/{wishlist_id}/items – Add item into target wishlist

GET /wishlists/{wishlist_id}/items/{item_id} – Get item by its id from target wishlist

PUT /wishlists/{wishlist_id} – Updates an existing wishlist

DELETE /wishlists/{wishlist_id}/items/{item_id} – Delete item by its id from target wishlist

You can now run behave and nosetests to run the BDD and TDD tests respectively.

Run the tests using nose

    $ nosetests

Nose is configured via the included setup.cfg file to automatically include the flags --with-spec --spec-color so that red-green-refactor is meaningful. If you are in a command shell that supports colors, passing tests will be green while failing tests will be red.

Nose is also configured to automatically run the coverage tool and you should see a percentage of coverage report at the end of your tests. If you want to see what lines of code were not tested use:

    $ coverage report -m

This is particularly useful because it reports the line numbers for the code that is not covered so that you can write more test cases to get higher code coverage.

You can also manually run nosetests with coverage (but setup.cfg does this already)

    $ nosetests --with-coverage --cover-package=service

Run the tests using behave

    $ behave

Behave is configured in features directory.

vagrant up
vagrant ssh
cd /vagrant
pylint --rcfile=pylint.conf service/*.py
pylint --rcfile=pylint.conf tests/*.py

Creates an IAM role for use as an ECS task execution role.

module "ecs_task_execution_role" {
  source = "dod-iac/ecs-task-execution-role/aws"

  allow_create_log_groups    = true
  cloudwatch_log_group_names = ["*"]
  name = format("app-%s-task-execution-role-%s", var.application, var.environment)

  tags  = {
    Application = var.application
    Environment = var.environment
    Automation  = "Terraform"
  }
}

Creates an IAM role for use as an ECS task execution role that writes to a specific list of encrypted CloudWatch log groups.

module "cloudwatch_kms_key" {
  source = "dod-iac/cloudwatch-kms-key/aws"

  name = format("alias/app-%s-cloudwatch-logs-%s", var.application, var.environment)

  tags  = {
    Application = var.application
    Environment = var.environment
    Automation  = "Terraform"
  }
}

resource "aws_cloudwatch_log_group" "main" {
  name              = format("/aws/ecs/app-%s-%s", var.application, var.environment)
  retention_in_days = 1 # expire logs after 1 day
  kms_key_id        = module.cloudwatch_kms_key.aws_kms_key_arn

  tags  = {
    Application = var.application
    Environment = var.environment
    Automation  = "Terraform"
  }
}

module "ecs_task_execution_role" {
  source = "dod-iac/ecs-task-execution-role/aws"

  cloudwatch_log_group_names = [module.cloudwatch_log_group.name]
  name = format("app-%s-task-execution-role-%s", var.application, var.environment)

  tags  = {
    Application = var.application
    Environment = var.environment
    Automation  = "Terraform"
  }
}

Run all terratest tests using the terratest script. If using aws-vault, you could use aws-vault exec $AWS_PROFILE -- terratest. The AWS_DEFAULT_REGION environment variable is required by the tests. Use TT_SKIP_DESTROY=1 to not destroy the infrastructure created during the tests. Use TT_VERBOSE=1 to log all tests as they are run. The go test command can be executed directly, too.

Terraform 0.13. Pin module version to ~> 1.0.0 . Submit pull-requests to main branch.

Terraform 0.11 and 0.12 are not supported.

This project constitutes a work of the United States Government and is not subject to domestic copyright protection under 17 USC § 105. However, because the project utilizes code licensed from contributors and other third parties, it therefore is licensed under the MIT License. See LICENSE file for more information.

No modules.

Make a live CD Debian with dwagent (https://www.dwservice.net/)

sudo apt install debootstrap xorriso live-build syslinux squashfs-tools isolinux grub-efi-amd64-bin

cp config.dist config

Change livework and os_version to your needs.

sudo ./make_iso.sh

If no error, you should get dwlive-debian-amd64.iso.
Now, you can copy the iso on a usb stick.

«IT support» = the person helping
«client» = the person who needs help

Sign up on https://www.dwservice.net/
Go to Agents. Add new Agent.
Send the code (like 123-456-789) and the dwlive’s iso to your client
Wait your client enter the code.
Afer that, you have access to his computer.

If you whant to fix de Gnu/Linux, you can run it with display.
This is how to do.
Mount the OS partition :

mount /dev/sda1 /media/ # change sda1 to your conf

or for lvm

vgscan
vgchange -ay ubuntu-vg # change ubuntu-vg to your conf
mount /dev/ubuntu-vg/ubuntu-lv /media/

Start X server :

./1_startx.sh

Now on https://www.dwservice.net/, you can select a screen.
Go to the screen tab, and

2_run_os.sh

After login, you can do :

export DISPLAY=:1
mate-session& # or cinamon-session or kde-session or...

Copy dwlive on a usb stick.
Boot the computer on the usb stick.
Valide questions about the key board. If you didn’t know the answer, just press enter.
At the question «Please choose an operation», select 1.
Then enter the code given by your IT support (like 123-456-789).

mongomove is a utility tool that facilitates the migration of databases from one MongoDB server to another. It’s especially handy for transferring data between remote servers and local development environments.

go install github.com/bounoable/mongomove/cmd/mongomove@latest

go get github.com/bounoable/mongomove

Move databases from one server to another:

mongomove -source mongodb://127.0.0.1:27017 -target mongodb://127.0.0.1:27018

Migrate databases that start with a specific prefix:

mongomove -source mongodb://127.0.0.1:27017 -target mongodb://127.0.0.1:27018 -prefix my_

To bypass the confirmation prompt:

mongomove -source mongodb://127.0.0.1:27017 -target mongodb://127.0.0.1:27018 -confirm

Specify the number of documents to process in a single batch (default is 100):

mongomove -source mongodb://127.0.0.1:27017 -target mongodb://127.0.0.1:27018 -b 500

Set the number of concurrent database imports. By default, mongomove uses the number of CPUs available:

mongomove -source mongodb://127.0.0.1:27017 -target mongodb://127.0.0.1:27018 -p 2

Prevent the creation of indexes during import:

mongomove -source mongodb://127.0.0.1:27017 -target mongodb://127.0.0.1:27018 -indexes false

For a more detailed output:

mongomove -source mongodb://127.0.0.1:27017 -target mongodb://127.0.0.1:27018 -v

MIT.

• Any OS (Windows/OS X/Linux)
• Java 8 — not higher!
• Apache Ant (a build tool)

NB! Only use ant command when compiling Tracer, any flags (like verbose) will later result in “Unable to access jarfile” error.

git clone http://vcs.etrap.eu/tracer-framework/tracer.git

cd tracer

ant

java -Xmx600m -Deu.etrap.medusa.config.ClassConfig=conf/tracer_config.xml -jar tracer.jar > FILENAME.OUT

• Your data must be a single .txt file in tracer/data/corpora/*some-folder*
• Check and update tracer/conf/tracer_config.xml before running

• Download & installation
• Troubleshooting
• Data format
• Configuration
• Output

• Java 8 — not higher!
• Scala
• Sbt ( a build tool for JVM languages)
• Apache Spark
  • Comes with Java 11
  • Depends on Hadoop, which has native libraries that aren’t supported in OS X → won’t run on a Mac

NB! Build Passim with sbt before installing Apache Spark. Spark comes with Java 11, which results in build conflicts when you are compiling Passim with sbt.

git clone https://github.com/dasmiq/passim.git

cd passim

build/sbt package

This should produce a runnable .jar in target/scala_*/passim*.jar.

passim "{input.json,directory-of-json-files,some*.json.bz2}" output

GitHub repo

This project was bootstrapped with React Native CLI.

To see how you can run this app for iOS or Android please see the Running your React Native application section from the React Native Documentation. For this sample, we’ll ignore those details.

1. npm uninstall @react-native-community/eslint-config – React Native 0.63.4 (at the moment of this writing) comes with a predefined eslint config, but we’ll remove that package because we’ll create our own config.

2. npm uninstall eslint – React Native 0.63.4 (at the moment of this writing) doesn’t come with the latest eslint version, so we’ll simply uninstall it and then install it again to pull the latest version.

3. npm install eslint --save-dev – install the latest eslint package version.

4. npx eslint --init – set up a configuration file for eslint. This command will ask you a few questions via CLI. Here’s a list of them, and the answers we’ll need to choose (✔ and ❯ symbols indicate the selected answers):

# question 1:
? How would you like to use ESLint? …
  To check syntax only
  To check syntax and find problems
❯ To check syntax, find problems, and enforce code style

# question 2:
? What type of modules does your project use? …
❯ JavaScript modules (import/export)
  CommonJS (require/exports)
  None of these

# question 3:
? Which framework does your project use? …
❯ React
  Vue.js
  None of these

# question 4 (select "No", because we won't add TypeScript support for this project):
? Does your project use TypeScript? › No / Yes

# question 5:
? Where does your code run? …
  Browser
✔ Node

# question 6:
? How would you like to define a style for your project? …
❯ Use a popular style guide
  Answer questions about your style
  Inspect your JavaScript file(s)

# question 7 (we'll rely on Airbnb's JavaScript style guide here):
? Which style guide do you want to follow? …
❯ Airbnb: https://github.com/airbnb/javascript
  Standard: https://github.com/standard/standard
  Google: https://github.com/google/eslint-config-google

# question 8:
? What format do you want your config file to be in? …
  JavaScript
  YAML
❯ JSON

# the final prompt here is where eslint will ask you if you want to install all the necessary dependencies. Select "Yes" and hit enter:
Checking peerDependencies of eslint-config-airbnb@latest
The config that you have selected requires the following dependencies:

eslint-plugin-react@^7.21.5 eslint-config-airbnb@latest eslint@^5.16.0 || ^6.8.0 || ^7.2.0 eslint-plugin-import@^2.22.1 eslint-plugin-jsx-a11y@^6.4.1 eslint-plugin-react-hooks@^4 || ^3 || ^2.3.0 || ^1.7.0

? Would you like to install them now with npm? › No / Yes

As a result, you’ll end up having a .eslintrc.json file in the root of your project, which looks like so (we’ll modify it a little bit later on):

{
    "env": {
        "es2021": true,
        "node": true,
    },
    "extends": [
        "plugin:react/recommended",
        "airbnb"
    ],
    "parserOptions": {
        "ecmaFeatures": {
            "jsx": true
        },
        "ecmaVersion": 12,
        "sourceType": "module"
    },
    "plugins": [
        "react"
    ],
    "rules": {
    }
}

NOTE: React Native comes (at the moment of this writing) with a .eslintrc.js config, and if that’s still the case for you, then simply remove it, since we’ll use the JSON format of that config.

6. React Hooks are pretty popular at this point and most likely every new React Native project will make use of them, so let’s add the recommended ESLint rules for hooks. For that, update the extends section of your .eslintrc.json file like so:

{
    //...
    "extends": [
        "plugin:react/recommended",
        "airbnb",
        "airbnb/hooks"
    ],
    //...
}

7. npm install --save-dev eslint-plugin-react-native – add support for React Native specific ESLint rules. After installing this package, update the plugins section of your .eslintrc.json file like so:

{
    //...
    "plugins": [
        "react",
        "react-native"
    ],
    //...
}

8. Create a .eslintignore file in the root on your project to tell ESLint to ignore specific files and directories, and then add the following contents:

node_modules/

In our case, we simply want to ignore the node_modules folder from being linted.

9. Last step here, is to configure your code editor to lint the code for you. If you’re a VS Code user, simply install the ESLint VS Code extension. The only ESLint configuration you need to add to your VS Code settings is the following:

{
    "editor.codeActionsOnSave": {
        "source.fixAll.eslint": true
    }
}

NOTE: You may want to add these VS Code settings as Workspace settings instead of User settings, meaning that they will only apply to this specific project and not to any project you’ll open in VS Code. Read more on the VS Code Documentation page.

1. npm install --save-dev --save-exact prettier – add the prettier package as a dev dependency to your project. We’ll also install and use the Prettier VS Code extension later on, which already comes with Prettier package bundled in, but in general it’s a good practice to add the npm package to your project directly as well, just in case some people won’t use VS Code as their code editor of choice.

2. npm install --save-dev eslint-config-prettier – we’ll use Prettier for code formatting concerns, and ESLint for code-quality concerns, so we need to turns off all ESLint rules that are unnecessary or might conflict with Prettier. Once the package has been installed, we need to update the extends section of your .eslintrc.json file like so:

{
    //...
    "extends": [
        "plugin:react/recommended",
        "airbnb",
        "airbnb/hooks",
        "prettier",
        "prettier/react"
    ],
    //...
}

3. Create a .prettierrc.json configuration file in the root of your project with the following options:

{
    "arrowParens": "always",
    "bracketSpacing": true,
    "jsxBracketSameLine": false,
    "jsxSingleQuote": false,
    "quoteProps": "as-needed",
    "singleQuote": true,
    "semi": true,
    "printWidth": 100,
    "useTabs": false,
    "tabWidth": 2,
    "trailingComma": "es5"
}

For more Prettier configuration options and an explanation of what each option does, see Prettier Documentation.

NOTE: React Native comes (at the moment of this writing) with a .prettierrc config already, and if that’s still the case for you, then you can still use that config file instead of creating a new .prettierrc.json one. They both use the JSON format for specifying configuration options.

4. Last step here, is to configure your code editor to format your code using Prettier. If you’re a VS Code user, simply install the Prettier VS Code extension. After the extension has been installed, add the following settings to your VS Code JSON config:

{
    "editor.defaultFormatter": "esbenp.prettier-vscode",
    "editor.formatOnSave": true
}

If you’re planning to have your React Native components written in .js files (which how this sample React Native project does), then you’ll need to update the react/jsx-filename-extension ESLint rule for React to allow JSX in .js files. The final version of your .eslintrc.json file should look like this.

You can enable/disable/modify any ESLint rules within the rules section of your .eslintrc.json file.