CI: Standardize the workflow for testing and changing the UUID (JuliaLang#129)

(cherry picked from commit cd002c3)

Author: DilumAluthge

.ci/change_uuid.jl

@@ -0,0 +1,28 @@
+@static if Base.VERSION >= v"1.6"
+    using TOML
+    using Test
+else
+    using Pkg: TOML
+    using Test
+end
+
+# To generate the new UUID, we simply modify the first character of the original UUID
+const original_uuid = "f43a241f-c20a-4ad4-852c-f6b1247861c6"
+const new_uuid      = "e43a241f-c20a-4ad4-852c-f6b1247861c6"
+
+# `@__DIR__` is the `.ci/` folder.
+# Therefore, `dirname(@__DIR__)` is the repository root.
+const project_filename = joinpath(dirname(@__DIR__), "Project.toml")
+
+@testset "Test that the UUID is unchanged" begin
+    project_dict = TOML.parsefile(project_filename)
+    @test project_dict["uuid"] == original_uuid
+end
+
+write(
+    project_filename,
+    replace(
+        read(project_filename, String),
+        r"uuid = .*?\n" => "uuid = \"$(new_uuid)\"\n",
+    ),
+)

.ci/test_and_change_uuid.jl

@@ -47,8 +47,7 @@ jobs:
             ${{ runner.os }}-test-${{ env.cache-name }}-
             ${{ runner.os }}-test-${{ matrix.os }}
             ${{ runner.os }}-
-      - run: julia --color=yes .ci/test_uuid_is_unchanged.jl
-      - run: julia --color=yes .ci/change_uuid.jl
+      - run: julia --color=yes .ci/test_and_change_uuid.jl
       - uses: julia-actions/julia-buildpkg@v1
       - uses: julia-actions/julia-runtest@v1
       - uses: julia-actions/julia-processcoverage@v1