IntelliJ/Rust are fast becoming buddies

Sublime Text 3 is my go to editor – I like the syntax highlighting, intuitive multi-caret support, and speed of grepping through my project or jumping to a file based on fuzzy filename matching. But it’s good to try new dev environments and the more I write Rust the more I want to leverage the type system to be more productive on large projects. And while I’m at it I want to support the Rust commercial ecosystem – I’m going to give the IntelliJ IDE (by JetBrains) a fair shake. It doesn’t hurt that IntelliJ is also a respected IDE for Java/Scala and Ruby (among many other supported platforms).

IntelliJ CE has been my exclusive Rust dev environment. And over the past few months it has gotten better and better. While still considered a work in progress it has helped me gain productivity. The plugin manager frequently alerts me of releases in the Rust plugin and the plugin repository reports upwards of 40k downloads – so more than a few Rustaceans are using the plugin! But at the same time I haven’t seen much advocacy or critiques.

In this post I want to go over everyday usage and hopefully convince you to give Intellij and the Rust plugin a try.

Setup

You’ll want to get the IntelliJ CE (community edition, aka, the free-to-use one). Go to the jetbrains download page. Once you have the base IDE installed you can add the Rust plugin from inside IntelliJ CE (IntelliJ > Preferences > Plugins > Browse Repositores, search for Rust, click install. Or: follow the IntelliJ rust’s instructions (click “install” for the pop up with actual instructions).

You will also need to clone down the entire Rust compiler project from github:

git clone https://github.com/rust-lang/rust.git

put that somewhere sane. I do all my coding from inside of ~/code/.

Then you need to go to IntelliJ IDEA > Preferences > Languages & Frameworks > Rust and set Standard Lib to something like /Users/xavierlange/code/rust/rust/src (note this is the rust/src folder inside of the cloned rust compiler project).

What about Racer?

You may have read about Rust’s racer project for a common IDE engine, enabling a variety of introspection and code creation behaviors common to Rust. The Intellij Rust plugin won’t be using that. The Idea folks have forged their own path, in their own words from the FAQ:

We would be able to leverage IntelliJ Platform infrastructure
for incremental analysis and indexing. With our own analysis
we can provide more flexible quick fixes, intentions and
typing assistance.

OK, that’s fine. If they are offering a more seamless experience with less config then that keeps me closer to what I like about Sublime Text. I’m not a gear head when it comes to IDEs – less config is better for me.

Key combos + helpful pointers for IntelliJ

  • cmd-b and click on any type, in your crate or in the stdlib: jump to the definition.
  • cmd-[ or cmd-]: goes backwards or forwards in your ‘jump’ history. Great so you can get back to your code.
  • cmd-shift-o: grep filenames in your project, hit enter to open file. Not as fuzzy as Sublime Text, won’t tolerate misspellings.
  • alt-shift and click: add another caret to the editor. Hit esc to leave multi-caret mode. Strictly less powerful than Sublime Text because you cannot click and drag carets across multiple lines. But can be handy.
  • ctrl-r: run your test suite. You’ll have to configure your run configurations but there’s an easy cargo target. Just set the command to test and make sure you click single instance only. I highly recommend you click Show backtrace on panic which sets the environmental variable RUST_BACKTRACE=1. Super handy.
  • ctrl-shift-r: run the current test based on your cursor (but make sure you select the ‘Cargo Test’ target when you’re done! it won’t switch back automatically)
  • cmd-shift-r: grep through all the code in your project
  • cmd-1/cmd-4: toggle project drawer/toggle run drawer
  • cmd-alt-l: basic rust reformatting (no rustfmt yet). won’t insert newlines.

Those keyboard shortcuts are the MVPs.

The integration with compiler errors is great. I run Rust nightly and the plugin has no problem highlighting errors so you can click and jump to definition. Handy when working through a backlog of compiler errors – which is very common when writing Rust!

Git integration is very workable; there’s also built in terminal if you want to skip the wizard-y interface.

Warts

  • Multi-caret is less useful than Sublime Text. Click and drag is key and IntelliJ requires you to click for each caret.
  • Cannot derive types in situations: loops, iterators, closures. Means you can’t jump to definition.
  • Sometimes cannot cross crate boundaries. I use a single git repo with two root modules: the library module and my test suite. The rust plugin cannot jump from the test suite to the library.
  • cmd-1, cmd-2, etc are reserved for opening the variety of drawers. I prefer jumping to tabs.
  • Can get lost in the preference. For example, Rust plugin related entries are found in at least two spots.
  • Plugin cannot jump to code based on backtrace
  • Noticeable impact on laptop’s battery life. Almost halved.

In any case

I’m impressed with the open development of the plugin. I highly recommend looking at the tickets to get a feel for the developers priorities.

The usual suspects of code completion, attractive rendering, and mostly-zippy interactions are great. The darcula theme is reminiscent of Sublime Text: easy on the eyes and attractive. As with most kitchen sink IDEs, you are best served on a fast machine. I recommend giving the Rust plugin a try.

The official project page has way more information

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