From 543a59f8e13b2d55773798e426b9c231cdee1275 Mon Sep 17 00:00:00 2001
From: Damon Bayer <xum8@cdc.gov>
Date: Tue, 12 May 2026 15:35:45 -0500
Subject: [PATCH 1/2] add julia

---
 Dockerfile | 15 +++++++++++++++
 bin/_info  |  6 ++++++
 2 files changed, 21 insertions(+)

diff --git a/Dockerfile b/Dockerfile
index be5a049..d0425a4 100644
--- a/Dockerfile
+++ b/Dockerfile
@@ -202,6 +202,21 @@ RUN : \
     && rm /tmp/dart.zip \
     && :
 
+ARG JULIA=1.12.6
+ARG JULIA_SHA256=bbabf3bef19421a9dbd24a767d807606ab85e444323b5a1c73ffe293fa3d079a
+ENV \
+    PATH=/opt/julia/bin:$PATH \
+    JULIA_DEPOT_PATH=/pc/julia_depot
+RUN : \
+    && echo 'lang: julia' \
+    && julia_minor="${JULIA%.*}" \
+    && curl --silent --location --output /tmp/julia.tgz "https://julialang-s3.julialang.org/bin/linux/x64/${julia_minor}/julia-${JULIA}-linux-x86_64.tar.gz" \
+    && echo "${JULIA_SHA256}  /tmp/julia.tgz" | sha256sum --check \
+    && mkdir /opt/julia \
+    && tar --strip-components=1 --directory /opt/julia -xf /tmp/julia.tgz \
+    && rm /tmp/julia.tgz \
+    && :
+
 ENV \
     PATH=/opt/r/bin/:$PATH \
     RENV_CONFIG_CACHE_ENABLED=false \
diff --git a/bin/_info b/bin/_info
index 1bb5d50..a426512 100755
--- a/bin/_info
+++ b/bin/_info
@@ -89,6 +89,12 @@ def main() -> int:
         _call('go', 'version')
     print()
 
+    print('## julia')
+    print()
+    with _console():
+        _call('julia', '--version')
+    print()
+
     print('## lua')
     print()
     with _console():

From 9ec5dbd56e2c8b6a05f846083d5e19241ed18697 Mon Sep 17 00:00:00 2001
From: Damon Bayer <xum8@cdc.gov>
Date: Mon, 18 May 2026 11:59:30 -0500
Subject: [PATCH 2/2] Update test

---
 bin/test | 36 ++++++++++++++++++++++++++++++++++++
 1 file changed, 36 insertions(+)

diff --git a/bin/test b/bin/test
index 3d79362..fd49ff5 100755
--- a/bin/test
+++ b/bin/test
@@ -292,6 +292,40 @@ def test_can_run_dart_hook(tag: str, pc: str, podman: bool) -> None:
         _build_and_run(tag, tmpdir, pc, podman=podman)
 
 
+JULIA_HOOK = '''\
+repos:
+-   repo: local
+    hooks:
+    -   id: julia-format
+        name: julia-format
+        language: julia
+        entry: formatter.jl
+        additional_dependencies: [JuliaFormatter@2]
+        files: ^t\\.jl$
+        types: [julia]
+'''
+
+JULIA_FORMATTER = '''\
+using JuliaFormatter
+
+exit(all(path -> format_file(path; overwrite=false), ARGS) ? 0 : 1)
+'''
+
+
+def test_can_run_julia_hook(tag: str, pc: str, podman: bool) -> None:
+    with tempfile.TemporaryDirectory() as tmpdir:
+        subprocess.check_call(('git', 'init', tmpdir))
+        with open(os.path.join(tmpdir, '.pre-commit-config.yaml'), 'w') as f:
+            f.write(JULIA_HOOK)
+        with open(os.path.join(tmpdir, 'formatter.jl'), 'w') as f:
+            f.write(JULIA_FORMATTER)
+        with open(os.path.join(tmpdir, 't.jl'), 'w') as f:
+            f.write('f(x) = 2x + 3\n')
+        subprocess.check_call(('git', '-C', tmpdir, 'add', '.'))
+
+        _build_and_run(tag, tmpdir, pc, podman=podman)
+
+
 R_HOOK = '''\
 repos:
 -   repo: local
@@ -430,6 +464,8 @@ def main() -> int:
         test_can_run_conda_hook(full_tag, pc, podman=args.podman)
         print(' can run dart tools '.center(79, '='), flush=True)
         test_can_run_dart_hook(full_tag, pc, podman=args.podman)
+        print(' can run julia hooks '.center(79, '='), flush=True)
+        test_can_run_julia_hook(full_tag, pc, podman=args.podman)
         print(' can run R hooks '.center(79, '='), flush=True)
         test_can_run_r_hook(full_tag, pc, podman=args.podman)
         print(' can run lua hooks '.center(79, '='), flush=True)