add at-test-allocations

Author: JoshuaLampert

src/TrixiTest.jl

@@ -7,7 +7,7 @@ include("auxiliary.jl")
 include("macros.jl")
 
 export get_kwarg, append_to_kwargs
-export @trixi_test_nowarn, @test_trixi_include_base, @timed_testset, @trixi_testset
+export @trixi_test_nowarn, @test_trixi_include_base, @timed_testset, @trixi_testset, @test_allocations
 
 # re-export methods from TrixiBase
 export mpi_isroot, trixi_include

src/macros.jl

@@ -192,3 +192,19 @@ macro trixi_testset(name, expr)
         nothing
     end
 end
+
+"""
+    @test_allocations(mod, semi, sol, allocs)
+
+Test that the memory allocations of `mod.rhs!` are below `allocs`
+(e.g., from type instabilities), where `mod` is a module containing
+a method `rhs!(du, u, semi, t)`.
+"""
+macro test_allocations(mod, semi, sol, allocs)
+    quote
+        t = $(esc(sol)).t[end]
+        u = $(esc(sol)).u[end]
+        du = similar(u)
+        @test (@allocated $(esc(mod)).rhs!(du, u, $(esc(semi)), t)) < $(esc(allocs))
+    end
+end

test/runtests.jl

@@ -6,4 +6,5 @@ using TrixiTest
     include("test_testset.jl")
     include("test_test_trixi_include.jl")
     include("test_trixi_test_nowarn.jl")
+    include("test_test_allocations.jl")
 end

test/test_test_allocations.jl

@@ -0,0 +1,14 @@
+module TestAllocations
+    function rhs!(du, u, semi, t)
+        # Simulate some computation
+        du .= u .+ t
+        return du
+    end
+end
+
+@testset "@test_allocations" begin
+    semi = nothing
+    sol = (t = [1.0], u = [[1.0, 2.0]])
+    allocs = 1
+    @test_allocations(TestAllocations, semi, sol, allocs)
+end