scalafiddle/scalafiddle-editor

Web user interface for ScalaFiddle

ScalaFiddle editor

This project provides an online editor for creating, sharing and embedding Scala fiddles (little Scala programs that can run in your browser).

Usage

For documentation on how to use the ScalaFiddle editor, see the Welcome.

Hosting your own ScalaFiddle editor

ScalaFiddle has been designed to be easy to host on your own. It's published as Docker images (scalafiddle/scalafiddle-editor, scalafiddle/scalafiddle-router and scalafiddle/scalafiddle-core) which provide an easy way to set up your own service.

Contributing

If you'd like to contribute to the ScalaFiddle project, for example to add a new library dependency, read the contribution guide for more instructions on how to set up a local dev env for ScalaFiddle editor and core.

scalafiddle-editor's Issues

println(null) does not work like Predef.println

println(null) causes this to be displayed in the right pane:

ERROR: instance is null

(in red), and then the execution stops.

I expect that the following be displayed instead:

null

as if I had called println("null")

That the behavior is different from Predef.println is annoying when one tries to explain some bad behavior of a snippet, as we cannot demonstrate the real issue.

Add OG, oembed and iframely support

Add metadata to support OpenGraph, oembed and iframely, so that when a link to a fiddle is pasted in, say, Facebook or Slack, it will be expanded in a meaningful way.

Update Github authentication mechanism

Hello there!

On February 7th, 2020 at 00:52 (UTC) your application (ScalaFiddle) used an access token (with the User-Agent AHC/2.0) as part of a query parameter to access an endpoint through the GitHub API.

https://api.github.com/user

Please use the Authorization HTTP header instead as using the access_token query parameter is deprecated.

Depending on your API usage, we'll be sending you this email reminder once every 3 days for each token and User-Agent used in API calls made on your behalf.
Just one URL that was accessed with a token and User-Agent combination will be listed in the email reminder, not all.

Visit https://developer.github.com/changes/2019-11-05-deprecated-passwords-and-authorizations-api/#authenticating-using-query-parameters for more information.

Suggestion: Add horizontal/vertical layout configuration and allow Info/Libraries panel collapse/expand on the editor

Allowing the user to customize the editor (not only the embedded version) it should be possible to use the editor even in smartphones.

Display list of user's fiddles

For logged in users, provide a way to see what fiddles they have done in the past.

Collaborative editing

Allow multiple users to share a collaborative editing session for a fiddle.

A command to display the generated JS code

Scala.jsFiddle had a command (hidden behind Ctrl+J) to show the generated .js code for the snippet. Could we have something similar in Scala Fiddle?

Make println work better

Allow printing Any and do pattern matching to support DOM elements.

Support for JS/CSS dependencies

Allow specifying separate JS/CSS library dependencies (like React, Bootstrap etc) and also allow providing JS deps in for Scala libs.

Show a proper Welcome doc when opening a new fiddle

Use the right panel to disaply a "Getting started" style welcome message when creating a new fiddle. It should contain basic instructions on how to create a fiddle and links to further documentation.

Source of this doc should be a static web page hosted in Github pages for easy updates. The URL needs to be specified in configuration (so that it can be overridden with an env var)

Automatic type checking

When code passes client-side syntax check, perform type checking on a server. Be mindful about CPU usage and use a sufficient delay after edits to perform the check.

Go to definition -functionality

Add functionality for "Go to definition" where user can point a method/type with cursor and the appropriate source code for the definition is shown in the result view.

ref: https://github.com/scala/scala/blob/4c2c4c17bedb0627f6caaa44b0ab4c58a8949b71/src/repl/scala/tools/nsc/interpreter/PresentationCompilation.scala#L95

Real-time syntax check

Use FastParse to do client-side syntax checking of the Scala code.

Put ScalaTags and ScalaDom in the 'Selected' libraries by default

It appears as if scalatags and scaladom are included by default, but there isn't any indication in the UI. It would be nice if they were just added to the 'Selected' section by default. If it its not possible to remove them as a dependency, can we just show them under 'Selected' but not allow them to be removed?

Worksheet Mode

The Scala Worksheet seems to be popular in both Eclipse and IntelliJ. Users may find it useful if ScalaFiddle supported this mode as well.

For example, this would allow learners to follow along with videos for Functional Programming Principles in Scala coursera course using just a web browser.

Add Scalajs-React to Web Section of Libraries

Popular React.js implementation in scala that I currently use and would find helpful to have in scalafiddle.
https://github.com/japgolly/scalajs-react

Reload library information automatically

When library definitions change, ScalaFiddle needs to be fully restarted. Add a scheduled task to fetch new library data periodically and if it has changed, update internally.

Router will also need to poll for new libs from the editor and pass it on to compiler servers.

Allow loading library JSON directly from Github.

Add line numbers in UI style for small screens

It is very cumbersome to use ScalaFiddle for small screens without line numbers visible (e.g. it is difficult to jump to errors or have a view of error lines).

Handle up, down, left & right (iOS external keyboards)

It would be great if the editor handle the non standard keys event.key => UIKeyInputUpArrow, UIKeyInputDownArrow, UIKeyInputLeftArrow and UIKeyInputRightArrow, these events are the ones triggered when you use a external keyboard in iOS 11 and press Up, Down, Left & Right.

ScalaFiddle.scala:-5: ERROR: Linker used concurrently

ScalaFiddle.scala:-5: ERROR: Linker used concurrently

Macosx 10.11.5
Chrome Version 53.0.2785.89 (64-bit)

Foldable.traverse_ from cats on ScalaFiddle returns "undefined"

This is the fiddle:
https://scalafiddle.io/sf/CjQOb84/0

Code:

import cats.implicits._
import cats.Foldable

def parseInt(s: String): Option[Int] = {
  val x = Either.catchOnly[NumberFormatException](s.toInt).toOption
  x foreach println
  x
}

println(Foldable[List].traverse_(List("1", "2"))(parseInt).get)

Result:

1
2
undefined

Expected:

1
2
Some(3)

I am new to this Scala world, so please let me know if you recommend me posting the bug at Cats or at Scala.js

ScalaFiddle.scala:-5: ERROR: Library com.thoughtworks.binding %%% binding % 10.0.1 is not allowed

I choose Binding.scala 10.0.1 in "All versions", and I got an error

ScalaFiddle.scala:-5: ERROR: Library com.thoughtworks.binding %%% binding % 10.0.1 is not allowed

See https://scalafiddle.io/sf/dGkVqlV/9

Add latest tag for embedded scala fiddles

When embedding a scala fiddle, one has to specify the version of the fiddle. It would be nice to have a "latest" tag so one doesn't have to change the embedded link all the time when updating the fiddle.

Add link to scalafiddle's github page onScalafiddle.io

It would be awesome if there was a obvious link over to this github page on the scalafiddle.io site. I know its not necessarily hard to find the github page, but it would be nice if there was a 'fork me on github' type link somewhere obvious.

fix in Chrome

I cannot type anything in the editor when I use chrome (it works ok in Firefox)

Automatic code formatting

Use scalafmt either on the client or server side to provide automatic formatting of source code.

Support Dotty

Allow user to select Dotty as the Scala compiler

Losing code when accidentally closing the tab

One thing that trips me up with scalafiddle over and over, is that there’s no alert dialog when you try to exit the site. E.g. when I try to scroll to the left in the editor sometimes my browser will think I want to go ‘back’ and will leave all my changes gone for good. Same happens when I click on the scalafiddle logo by accident when I wanted to click the ‘Run’ button

We could persist current code in localstorage or implement an alert dialog before leaving the site.

Add ability (or improve docs for) adding a custom scala.js library

Apologies if I missed how to do this ... new to scalafiddle.

'Sign in with GitHub' not working

A server error occurred: Unexpected exception[SQLTransientConnectionException: postgre.db - Connection is not available, request timed out after 1000ms.]

My old scala-js-fiddle gist links result in 404

http://www.scala-js-fiddle.com/gist/11b36945bd5393042c11
http://www.scala-js-fiddle.com/gist/5dd062ed369a354a3c33
http://www.scala-js-fiddle.com/gist/68ccf07a8cdb5f537d9f

Implement responsive design

The site is not usable with mobile style devices. This could be fixed either by applying CSS media queries for appropriate sizes, or making the whole design fluid.

Applying a CSS-framework such as bootstrap (it's honestly been a while since I did UI styling so I don't know what's hip these days) would go a long way.

Provide search functionality

Search for fiddles with:

• name
• dependencies
• full-text source code

Add support for Google JS API library

Hi @ochrons,

this might not be the typical use case for Scalafiddle, but we wrote a Scala library that wraps the Google Apps Script API.
We are using an old forked version of Li Haoyi's Scalafiddle to compile standalone scripts like this to JS and run it in Google.
If you think that is a good show-case for Scalafiddle, I could prepare a PR that adds our library to the available libraries.

Support Scala 2.12

Allow user to select Scala 2.12 version

Service issue? "No suitable compiler available"

Currently, any edits to an existing fiddle cause "No suitable compiler available"

Example: https://scalafiddle.io/sf/9Xs6tIU/6 (compare to the previous https://scalafiddle.io/sf/9Xs6tIU/5)

Show type information

Add functionality to show the type information for a selected expression.

ref: https://github.com/scala/scala/blob/4c2c4c17bedb0627f6caaa44b0ab4c58a8949b71/src/repl/scala/tools/nsc/interpreter/PresentationCompilation.scala#L95

Improve smart reuse of compiler instances

Extract dep info in the router and select the best compiler based on past data on compilations with same libraries.

Use different compiler instances (when available) for auto-complete and compilation.

Direct a returning user to the same compiler as before when possible.

Document how to setup a custom ScalaFiddle service

How to set it up using Docker etc.

Add support for Karasiq/scalajs-bootstrap and lihaoyi/autowire

I didn't find any other place where to leave comments to you so I made an issue about my proposal.

Proposal 1: Add https://github.com/Karasiq/scalajs-bootstrap scalajs-bootstrap library to available libraries.
It is simple and light wrapper on top of bootstrap.

Proposal 2: Add https://github.com/lihaoyi/autowire autowire library to available libraries.
It is simple and typesafe RPC between client and server.

Add OutWatch to libraries

Please add OutWatch, the FRP UI framework to the list of usable libraries.

Options - Show Template - not clickable

The checkbox label is not clickable. Add the id and for attributes to link them together.

<!-- before -->
<input value="on" type="checkbox">
<label>Show template</label>

<!-- after -->
<input value="on" type="checkbox" id="show-template">
<label for="show-template">Show template</label>

Document development setup

Provide a doc explaining how to set up a dev env for ScalaFiddle, how to run it locally and how to make modifications to the code.