Formatting difference between VS Code and JuliaFormatter

Tooling VS Code
1

Hi,

I noticed that when using JuliaFormatter v2.1.6 with VS Code and a local project environment (Project.toml), there is a difference in how spaces are handled in indexing expressions, even without a .JuliaFormatter.toml file. I think the spaces are just an example.

Minimal example:

  • Create a folder with Project.toml containing:
[deps]
JuliaFormatter = "98e50ef6-434e-11e9-1051-2b60c6c9e899"
[compat]
JuliaFormatter = "2.1.6"

  • Instantiate the environment.

  • Create test.jl:

data = rand(2, 2, 2)
getindex(data,:,:,1) # here, no spaces around ":"
  • Save in VS Code with Julia extension → VS Code automatically adds spaces:
getindex(data, :, :, 1)
  • Format the file using the Julia formatter
julia --project=. -e 'using JuliaFormatter; format(".", verbose=true)'

CLI formatting removes the extra spaces and produces:

getindex(data,:,:,1)

Setup:

  • Julia: 1.10.3 (also tried in other Julia 1.10 version, no 1.11 available right now)
  • JuliaFormatter: 2.1.6 (from Project.toml)
  • VS Code Julia extension: latest stable
  • Only a Project.toml, Manifest.toml and test.jl exist in the folder
  • VS Code is using the local project environment

It seems the VS Code extension applies its own formatting on save, independently of JuliaFormatter CLI behavior or .JuliaFormatter.toml options. This leads to differences in spacing between VS Code format-on-save and CLI formatting.

Is there any way to discipline this? I have tried using a .JuliaFormatter.toml file, didn’t work.

I also posted this as an issue here.

2

See here for the reason of the bug: Formatting difference between VS Code and JuliaFormatter · Issue #3864 · julia-vscode/julia-vscode · GitHub

Using JuliaFormatter v1 fixes this issue until VS code upgrades to JuliaFormatter v2.