Missing complex tests (#34446)

Author: bramtayl

test/complex.jl

@@ -4,9 +4,22 @@ using LinearAlgebra
 
 @test reim(2 + 3im) == (2, 3)
 
+import Base: zero, real
+struct TestQuaternion{T} <: Number
+    scalar::T
+    i_component::T
+    j_component::T
+    k_component::T
+end
+zero(::Type{TestQuaternion{T}}) where {T} =
+    TestQuaternion(zero(T), zero(T), zero(T), zero(T))
+real(quaternion::TestQuaternion) = quaternion.scalar
+
 for T in (Int64, Float64)
     @test real(T) == T
     @test real(Complex{T}) == T
+    # TestQuaternions are neither real or complex
+    @test real(TestQuaternion{T}) == T
     @test complex(T) == Complex{T}
     @test complex(Complex{T}) == Complex{T}
 end
@@ -737,6 +750,8 @@ end
     @test isequal(atanh(complex( Inf, Inf)),complex(0.0, pi/2))
     @test isequal(atanh(complex( Inf,-Inf)),complex(0.0,-pi/2))
     @test isequal(atanh(complex( Inf, NaN)),complex(0.0, NaN))
+    # very big but not infinite
+    @test isequal(atanh(complex(4e200, NaN)),complex(NaN, NaN))
 
     @test isequal(atanh(complex(-Inf, 0.0)),complex(-0.0, pi/2))
     @test isequal(atanh(complex(-Inf,-0.0)),complex(-0.0,-pi/2))
@@ -978,6 +993,8 @@ end
         @test log1p(z) ≈ log(1 + z)
         @test exp2(z) ≈ exp(z * log(2))
         @test exp10(z) ≈ exp(z * log(10))
+        @test isequal(z^true, z)
+        @test isequal(z^0, complex(1.0,0.0))
     end
 end
 
@@ -1049,6 +1066,18 @@ end
         @test isequal(one(T) / complex(-zero(T), T(-Inf)), complex(-zero(T), zero(T)))
         @test isequal(one(T) / complex(-one(T),  T(-Inf)), complex(-zero(T), zero(T)))
         @test isequal(one(T) / complex(T(-NaN),  T(-Inf)), complex(-zero(T), zero(T)))
+
+        # divide complex by complex Inf
+        if T == Float64
+            @test_broken isequal(complex(one(T)) / complex(T(Inf), T(-Inf)), complex(zero(T), zero(T)))
+            @test_broken isequal(complex(one(T)) / complex(T(-Inf), T(Inf)), complex(-zero(T), -zero(T)))
+        elseif T == Float32
+            @test isequal(complex(one(T)) / complex(T(Inf), T(-Inf)), complex(zero(T), zero(T)))
+            @test_broken isequal(complex(one(T)) / complex(T(-Inf), T(Inf)), complex(-zero(T), -zero(T)))
+        else
+            @test isequal(complex(one(T)) / complex(T(Inf), T(-Inf)), complex(zero(T), zero(T)))
+            @test isequal(complex(one(T)) / complex(T(-Inf), T(Inf)), complex(-zero(T), -zero(T)))
+        end
     end
 end
 
@@ -1152,3 +1181,6 @@ end
 
 # real(C) with C a Complex Unionall
 @test real(Complex{<:AbstractFloat}) == AbstractFloat
+
+# complex with non-concrete eltype
+@test_throws ErrorException complex(Union{Complex{Int}, Nothing}[])