Add missing methods to round

base/complex.jl

@@ -1043,7 +1043,8 @@ function round(z::Complex, rr::RoundingMode=RoundNearest, ri::RoundingMode=rr; k
     Complex(round(real(z), rr; kwargs...),
             round(imag(z), ri; kwargs...))
 end
-
+round(::Type{Complex{T}}, x::Complex) where {T<:Real} = Complex(round(T, x.re), round(T, x.im))
+round(::Type{Complex{T}}, x::Real) where {T<:Real} = Complex(round(T, x))
 
 float(z::Complex{<:AbstractFloat}) = z
 float(z::Complex) = Complex(float(real(z)), float(imag(z)))

base/float.jl

@@ -318,6 +318,8 @@ trunc(::Type{Integer}, x::Float64) = trunc(Int,x)
 floor(::Type{T}, x::AbstractFloat) where {T<:Integer} = trunc(T,round(x, RoundDown))
 ceil(::Type{T}, x::AbstractFloat) where {T<:Integer} = trunc(T,round(x, RoundUp))
 round(::Type{T}, x::AbstractFloat) where {T<:Integer} = trunc(T,round(x, RoundNearest))
+round(::Type{T}, x::Float16) where {T<:Integer} = round(T, Float32(x))
+round(::Type{T}, x::Real) where {T<:Real} = T(round(x))
 
 round(x::Float64, r::RoundingMode{:ToZero})  = trunc_llvm(x)
 round(x::Float32, r::RoundingMode{:ToZero})  = trunc_llvm(x)

base/rational.jl

@@ -454,6 +454,7 @@ end
 trunc(::Type{T}, x::Rational) where {T} = round(T, x, RoundToZero)
 floor(::Type{T}, x::Rational) where {T} = round(T, x, RoundDown)
 ceil(::Type{T}, x::Rational) where {T} = round(T, x, RoundUp)
+round(::Type{T}, x::Rational) where {T<:Real} = round(T, x, RoundNearest)
 
 round(x::Rational, r::RoundingMode=RoundNearest) = round(typeof(x), x, r)
 
@@ -464,7 +465,7 @@ function round(::Type{T}, x::Rational{Tr}, r::RoundingMode=RoundNearest) where {
     convert(T, div(numerator(x), denominator(x), r))
 end
 
-function round(::Type{T}, x::Rational{Bool}, ::RoundingMode=RoundNearest) where T
+function round(::Type{T}, x::Rational{Bool}, ::RoundingMode=RoundNearest) where {T<:Real}
     if denominator(x) == false && (T <: Integer)
         throw(DivideError())
     end

test/complex.jl

@@ -963,6 +963,19 @@ end
     @test round(float(Complex(π, ℯ)), digits=3) == Complex(3.142, 2.718)
 end
 
+@testset "For issue #24021" begin
+    for T in (Int16, Int32, Int64, Int128), U in (Float32, Float64)
+        a = round(Complex{T}, Complex{U}(2.9, 1.1))
+        b = round(Complex{U}, Complex{T}(3, 1))
+        @test a.im isa T
+        @test b.im isa U
+        @test a == Complex(3,1)
+        @test b == Complex(3,1)
+        @test round(Complex{U}, T(3)) == Complex(3,0)
+        @test round(Complex{T}, U(2.9)) == Complex(3,0)
+    end
+end
+
 @testset "ComplexF16 arithmetic, PR #10003" begin
     @test Float16(1)+Float16(1)im === ComplexF16(1, 1)
     @test Float16(1)-Float16(1)im === Float16(1)+Float16(-1)im === ComplexF16(1, -1)

test/rounding.jl

@@ -77,6 +77,16 @@ end
         end
     end
 end
+
+@testset "For issue #24021" begin
+    types = [Float16, Float32, Float64, BigFloat, Int16, Int32, Int64, BigInt]
+    for T in types, S in types[1:4]
+        x = round(T, S(1.234))
+        @test x == 1
+        @test x isa T
+    end
+end
+
 @testset "fenv" begin
     @test Base.Rounding.from_fenv(Base.Rounding.to_fenv(RoundNearest)) == RoundNearest
     @test Base.Rounding.from_fenv(Base.Rounding.to_fenv(RoundToZero)) == RoundToZero