diff --git a/test/biosequences/indexing.jl b/test/biosequences/indexing.jl
index 3e571f36..c7d1470c 100644
--- a/test/biosequences/indexing.jl
+++ b/test/biosequences/indexing.jl
@@ -176,9 +176,9 @@ end
 
 @testset "BitIndex" begin
     ind = BioSequences.BitIndex{4, UInt64}(16)
-    BioSequences.BitsPerSymbol(ind) = BioSequences.BitsPerSymbol{4}()
-    BioSequences.bitwidth(UInt64) = 64
-    BioSequences.bitwidth(UInt16) = 16
-    BioSequences.prevposition(ind) == BioSequences.BitIndex{4, UInt64}(12)
-    BioSequences.nextposition(ind) == BioSequences.BitIndex{4, UInt64}(20)
-end
\ No newline at end of file
+    @test BioSequences.BitsPerSymbol(ind) == BioSequences.BitsPerSymbol{4}()
+    @test BioSequences.bitwidth(UInt64) == 64
+    @test BioSequences.bitwidth(UInt16) == 16
+    @test BioSequences.prevposition(ind) == BioSequences.BitIndex{4, UInt64}(12)
+    @test BioSequences.nextposition(ind) == BioSequences.BitIndex{4, UInt64}(20)
+end
diff --git a/test/search/pwm.jl b/test/search/pwm.jl
index 00e888a9..f4000b87 100644
--- a/test/search/pwm.jl
+++ b/test/search/pwm.jl
@@ -72,9 +72,9 @@
         @test maxscore(pwm) ≈ sum(maximum(raw, dims=1))
         @test maxscore(PWM{DNA}(zeros(4, 0))) === 0.0
         @test PWM(pfm .+ 0.1) isa PWM{DNA,Float64}  # pseudo count
-        @test_throws ArgumentError PWM{DNA}(hcat(m, [13, 14, 15]))
-        @test_throws ArgumentError PWM(pfm, prior=normalize([0,1,2,3], 1))
-        @test_throws ArgumentError PWM(pfm, prior=normalize([0,1,2,3], 1).+1e-3)
+        @test_throws Exception PWM{DNA}(hcat(m, [13, 14, 15]))
+        @test_throws Exception PWM(pfm, prior=normalize([0,1,2,3], 1))
+        @test_throws Exception PWM(pfm, prior=normalize([0,1,2,3], 1).+1e-3)
         @test all(pwm[i] === pwm[i] for i in eachindex(pwm))
         @test all(pwm[i,j] === raw[i,j] for i in 1:4, j in 1:3)
         @test all(pwm[ACGT[i],j] === pwm[i,j] for i in 1:4, j in 1:3)