Add adjoint(::Missing) method

Author: quinnj

base/missing.jl

@@ -68,11 +68,11 @@ for f in (:(!), :(~), :(+), :(-), :(identity), :(zero), :(one), :(oneunit),
           :(acos), :(acosh), :(asin), :(asinh), :(atan), :(atanh),
           :(sin), :(sinh), :(cos), :(cosh), :(tan), :(tanh),
           :(exp), :(exp2), :(expm1), :(log), :(log10), :(log1p),
-          :(log2), :(exponent), :(sqrt), :(gamma), :(lgamma),
+          :(log2), :(Math.exponent), :(sqrt), :(Math.gamma), :(Math.lgamma),
           :(iseven), :(ispow2), :(isfinite), :(isinf), :(isodd),
           :(isinteger), :(isreal), :(isnan), :(isempty),
-          :(iszero), :(transpose), :(float))
-    @eval Math.$(f)(::Missing) = missing
+          :(iszero), :(transpose), :(adjoint), :(float))
+    @eval $(f)(::Missing) = missing
 end
 
 for f in (:(Base.zero), :(Base.one), :(Base.oneunit))

test/missing.jl

@@ -150,7 +150,7 @@ Base.one(::Type{Unit}) = 1
                             identity, zero, one, oneunit,
                             iseven, isodd, ispow2,
                             isfinite, isinf, isnan, iszero,
-                            isinteger, isreal, isempty, transpose, float]
+                            isinteger, isreal, isempty, transpose, adjoint, float]
 
     # All elementary functions return missing when evaluating missing
     for f in elementary_functions
@@ -218,6 +218,7 @@ end
     x = convert(Vector{Union{Int, Missing}}, [missing])
     @test isa(x, Vector{Union{Int, Missing}})
     @test isequal(x, [missing])
+    @test eltype(adjoint([1, missing])) == Union{Int, Missing}
 end
 
 @testset "== and != on arrays" begin