Canonicalize tests to @safetestset for module isolation

Wrap each independent top-level test unit in `@safetestset` so it runs in its
own module, matching the canonical OrdinaryDiffEq structure (per-unit isolation
+ world-age safety). The GROUP dispatch ladder (All/Core/nopre), the nopre
activated-env path, and all assertions are unchanged.

Units converted:
  - runtests.jl: `@testset "FunctionWrappersWrappers.jl" begin include("basictests.jl") end`
    -> `@safetestset ... begin include("basictests.jl") end`. basictests.jl
    already carries its own `using FunctionWrappersWrappers` / `using Test`, and
    its inner grouping `@testset`s stay plain (the file-level @safetestset already
    isolates the unit as one module).
  - runtests.jl: "BigFloat support" and "UnionAll return types" -> @safetestset,
    each with self-contained `using FunctionWrappersWrappers` / `using Test`.
  - nopre/jet_tests.jl: "JET static analysis" -> @safetestset. Because the body
    uses the `@test_opt` package macro (which must be imported before the body is
    macroexpanded), the body was extracted to nopre/jet_tests_impl.jl (top-level
    `using JET: @test_opt` runs before any `@test_opt` is parsed) and the
    @safetestset just does `include("jet_tests_impl.jl")` — the canonical
    OrdinaryDiffEq shape. Inline would hit `UndefVarError: @test_opt`.

Add SafeTestsets to test deps: main Project.toml [extras]/[targets].test/[compat]
and nopre/Project.toml [deps] (the nopre env is activated + instantiated at run
time, so instantiate resolves SafeTestsets without a pre-baked Manifest entry).

Verified locally on Julia 1.11: GROUP=All passes (21 + 5 + 2) and GROUP=nopre
passes (7 + 5 + 2). Runic-clean.

Co-Authored-By: Chris Rackauckas <accounts@chrisrackauckas.com>
Co-Authored-By: Claude Opus 4.8 (1M context) <noreply@anthropic.com>

Author: ChrisRackauckas

Project.toml

@@ -11,12 +11,14 @@ TruncatedStacktraces = "781d530d-4396-4725-bb49-402e4bee1e77"
 [compat]
 FunctionWrappers = "1"
 PrecompileTools = "1"
+SafeTestsets = "0.1, 1"
 TruncatedStacktraces = "1"
 julia = "1.10"
 
 [extras]
 Pkg = "44cfe95a-1eb2-52ea-b672-e2afdf69b78f"
+SafeTestsets = "1bc83da4-3b8d-516f-aca4-4fe02f6d838f"
 Test = "8dfed614-e22c-5e08-85e1-65c5234f0b40"
 
 [targets]
-test = ["Pkg", "Test"]
+test = ["Pkg", "Test", "SafeTestsets"]

test/nopre/Project.toml

@@ -1,4 +1,5 @@
 [deps]
 FunctionWrappersWrappers = "77dc65aa-8811-40c2-897b-53d922fa7daf"
 JET = "c3a54625-cd67-489e-a8e7-0a5a0ff4e31b"
+SafeTestsets = "1bc83da4-3b8d-516f-aca4-4fe02f6d838f"
 Test = "8dfed614-e22c-5e08-85e1-65c5234f0b40"

test/nopre/jet_tests.jl

@@ -1,30 +1,5 @@
-using FunctionWrappersWrappers
-using JET: JET, @test_opt
-using Test
+using SafeTestsets
 
-@testset "JET static analysis" begin
-    # Test that the main call path is type-stable (no fallback)
-    fwplus = FunctionWrappersWrapper(
-        +, (Tuple{Float64, Float64}, Tuple{Int, Int}), (
-            Float64, Int,
-        )
-    )
-
-    # Core functionality should be type-stable
-    @test_opt target_modules = (FunctionWrappersWrappers,) fwplus(4.0, 8.0)
-    @test_opt target_modules = (FunctionWrappersWrappers,) fwplus(4, 8)
-
-    # Test single-argument wrapper
-    fwexp2 = FunctionWrappersWrapper(
-        exp2, (Tuple{Float64}, Tuple{Float32}, Tuple{Int}), (Float64, Float32, Float64)
-    )
-    @test_opt target_modules = (FunctionWrappersWrappers,) fwexp2(4.0)
-    @test_opt target_modules = (FunctionWrappersWrappers,) fwexp2(4.0f0)
-    @test_opt target_modules = (FunctionWrappersWrappers,) fwexp2(4)
-
-    # Verify no errors detected by JET.report_call for core paths
-    rep = JET.report_call(fwplus, (Float64, Float64))
-    @test length(JET.get_reports(rep)) == 0
-    rep = JET.report_call(fwplus, (Int, Int))
-    @test length(JET.get_reports(rep)) == 0
+@safetestset "JET static analysis" begin
+    include("jet_tests_impl.jl")
 end

test/nopre/jet_tests_impl.jl

@@ -0,0 +1,28 @@
+using FunctionWrappersWrappers
+using JET: JET, @test_opt
+using Test
+
+# Test that the main call path is type-stable (no fallback)
+fwplus = FunctionWrappersWrapper(
+    +, (Tuple{Float64, Float64}, Tuple{Int, Int}), (
+        Float64, Int,
+    )
+)
+
+# Core functionality should be type-stable
+@test_opt target_modules = (FunctionWrappersWrappers,) fwplus(4.0, 8.0)
+@test_opt target_modules = (FunctionWrappersWrappers,) fwplus(4, 8)
+
+# Test single-argument wrapper
+fwexp2 = FunctionWrappersWrapper(
+    exp2, (Tuple{Float64}, Tuple{Float32}, Tuple{Int}), (Float64, Float32, Float64)
+)
+@test_opt target_modules = (FunctionWrappersWrappers,) fwexp2(4.0)
+@test_opt target_modules = (FunctionWrappersWrappers,) fwexp2(4.0f0)
+@test_opt target_modules = (FunctionWrappersWrappers,) fwexp2(4)
+
+# Verify no errors detected by JET.report_call for core paths
+rep = JET.report_call(fwplus, (Float64, Float64))
+@test length(JET.get_reports(rep)) == 0
+rep = JET.report_call(fwplus, (Int, Int))
+@test length(JET.get_reports(rep)) == 0

test/runtests.jl

@@ -1,9 +1,10 @@
 using Test, Pkg
+using SafeTestsets
 
 const GROUP = get(ENV, "GROUP", "All")
 
 if GROUP == "All" || GROUP == "Core"
-    @testset "FunctionWrappersWrappers.jl" begin
+    @safetestset "FunctionWrappersWrappers.jl" begin
         include("basictests.jl")
     end
 end
@@ -15,7 +16,10 @@ if GROUP == "nopre"
     include("nopre/jet_tests.jl")
 end
 
-@testset "BigFloat support" begin
+@safetestset "BigFloat support" begin
+    using FunctionWrappersWrappers
+    using Test
+
     fwplus_big = FunctionWrappersWrapper(
         +,
         (Tuple{BigFloat, BigFloat}, Tuple{Float64, Float64}),
@@ -36,7 +40,10 @@ end
     @test fwsin_big(1.0) === sin(1.0)
 end
 
-@testset "UnionAll return types" begin
+@safetestset "UnionAll return types" begin
+    using FunctionWrappersWrappers
+    using Test
+
     # Test that UnionAll types (like AbstractArray{Float64}) work as return types
     function double_array(x::AbstractArray{Float64})
         return x .* 2