julia-syntax-lowering

Development

Develop and test JuliaSyntax and JuliaLowering in Julia's source tree. Use when modifying JuliaSyntax/ or JuliaLowering/, running package or targeted tests, or checking JuliaLowering execution.

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Source SKILL.md: https://github.com/JuliaLang/julia/blob/HEAD/doc/src/devdocs/agents/skills/julia-syntax-lowering/SKILL.md

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JuliaSyntax & JuliaLowering development

Use this when modifying JuliaSyntax/ or JuliaLowering/ source, tests, or package metadata.

Testing JuliaSyntax

Run package tests from the repository root:

julia --project=JuliaSyntax -e 'using Pkg; Pkg.test()'

JuliaSyntax is not tied only to the in-tree Julia runtime; if a change may be version-sensitive, test it with the relevant installed Julia version(s).

Testing JuliaLowering

Prefer the in-tree Julia runtime because compatibility with the Julia runtime may matter:

./usr/bin/julia --project=JuliaLowering -e 'using Pkg; Pkg.test()'

If ./usr/bin/julia is unavailable, note that limitation and use an available julia executable only for preliminary validation.

In this repository, JuliaLowering/Project.toml points its JuliaSyntax dependency at the sibling JuliaSyntax checkout (path = "../JuliaSyntax"). Therefore, JuliaSyntax changes can affect JuliaLowering. When a JuliaSyntax change may affect lowering behavior or syntax data consumed by JuliaLowering, run the JuliaLowering test command as well.

Targeted JuliaLowering tests

For targeted JuliaLowering test execution, include JuliaLowering/test/utils.jl before the test file, matching JuliaLowering/test/runtests.jl:

./usr/bin/julia --project=JuliaLowering -e 'cd("JuliaLowering/test") do; include("utils.jl"); include("scopes.jl"); end'

For _ir.jl fixtures, call test_ir_cases after loading utils.jl:

./usr/bin/julia --project=JuliaLowering -e 'cd("JuliaLowering/test") do; include("utils.jl"); test_ir_cases("scopes_ir.jl"); end'

Trying JuliaLowering execution

For quick execution checks, run with the in-tree Julia runtime and the JuliaLowering project:

./usr/bin/julia --project=JuliaLowering

Then either evaluate code explicitly through JuliaLowering:

using JuliaLowering
JuliaLowering.include_string(Main, "1 + 2")

or activate JuliaLowering as the process lowerer, then evaluate subsequent code normally:

using JuliaLowering
JuliaLowering.activate!()

1 + 2

Use include("path/to/file.jl") after activation when checking a file. When using JuliaLowering.activate!() from -e, make the code under test a separate top-level statement after activation, or put it in include(...).