From ca80deb6b05506dff32076cede03010cdf46f700 Mon Sep 17 00:00:00 2001
From: Sebastian Stock <42280794+sostock@users.noreply.github.com>
Date: Thu, 31 Oct 2024 15:44:35 +0100
Subject: [PATCH] cis/cispi without explicit uconvert (calls sincos/sincospi)

---
 src/Unitful.jl    | 2 +-
 src/quantities.jl | 6 +++++-
 test/runtests.jl  | 4 +++-
 3 files changed, 9 insertions(+), 3 deletions(-)

diff --git a/src/Unitful.jl b/src/Unitful.jl
index e8919035..376755c8 100644
--- a/src/Unitful.jl
+++ b/src/Unitful.jl
@@ -7,7 +7,7 @@ import Base: min, max, floor, ceil, real, imag, conj
 import Base: complex, widen, reim # handled in complex.jl
 import Base: exp, exp10, exp2, expm1, log, log10, log1p, log2
 import Base: sin, cos, tan, asin, acos, atan, sinh, cosh, tanh, asinh, acosh, atanh,
-             sinpi, cospi, sinc, cosc, cis
+             sinpi, cospi, sinc, cosc, cis, cispi
 import Base: eps, mod, rem, div, fld, cld, divrem, trunc, round, sign, signbit
 import Base: isless, isapprox, isinteger, isreal, isinf, isfinite, isnan
 import Base: copysign, flipsign
diff --git a/src/quantities.jl b/src/quantities.jl
index 64139c63..5bcf24ab 100644
--- a/src/quantities.jl
+++ b/src/quantities.jl
@@ -206,11 +206,15 @@ sqrt(x::AbstractQuantity) = Quantity(sqrt(x.val), sqrt(unit(x)))
 cbrt(x::AbstractQuantity) = Quantity(cbrt(x.val), cbrt(unit(x)))
 
 for _y in (:sin, :cos, :tan, :asin, :acos, :atan, :sinh, :cosh, :tanh, :asinh, :acosh, :atanh,
-           :sinpi, :cospi, :tanpi, :sinc, :cosc, :cis, :cispi, :sincospi)
+           :sinpi, :cospi, :tanpi, :sinc, :cosc, :sincospi)
     if isdefined(Base, _y)
         @eval Base.$(_y)(x::DimensionlessQuantity) = Base.$(_y)(uconvert(NoUnits, x))
     end
 end
+cis(x::DimensionlessQuantity{<:Real}) = Complex(reverse(sincos(x))...)
+cis(x::DimensionlessQuantity{<:Complex}) = exp(-imag(x)) * Complex(reverse(sincos(real(x)))...)
+cispi(x::DimensionlessQuantity{<:Real}) = Complex(reverse(sincospi(x))...)
+cispi(x::DimensionlessQuantity{<:Complex}) = exp(-(π*imag(x))) * Complex(reverse(sincospi(real(x)))...)
 
 atan(y::AbstractQuantity{T1,D,U1}, x::AbstractQuantity{T2,D,U2}) where {T1,T2,D,U1,U2} =
     atan(promote(y,x)...)
diff --git a/test/runtests.jl b/test/runtests.jl
index 8635f9a0..0da1f85b 100644
--- a/test/runtests.jl
+++ b/test/runtests.jl
@@ -741,7 +741,8 @@ Base.:(<=)(x::Issue399, y::Issue399) = x.num <= y.num
         @test @inferred(cbrt(m^3)) === m
         @test (2m)^3 === 8*m^3
         @test (8m)^(1//3) === 2.0*m^(1//3)
-        @test @inferred(cis(90°)) ≈ im
+        @test @inferred(cis(90°)) == im
+        @test @inferred(cis((90 - rad2deg(1)*im)°)) ≈ ℯ*im
 
         # Test inferrability of literal powers
         _pow_m3(x) = x^-3
@@ -806,6 +807,7 @@ Base.:(<=)(x::Issue399, y::Issue399) = x.num <= y.num
         @test @inferred(cosc(1ft/3inch)) === 0.25
         if isdefined(Base, :cispi)
             @test @inferred(cispi(rad/2)) === complex(0.0, 1.0)
+            @test @inferred(cispi(rad/2 + im*rad)) ≈ complex(0.0, exp(-π))
         end
         if isdefined(Base, :sincospi)
             @test @inferred(sincospi(rad/2)) === (1.0, 0.0)