From b6316e4d6f711222e27a3a47c020327a96e8f9b6 Mon Sep 17 00:00:00 2001
From: john verzani <jverzani@gmail.com>
Date: Tue, 16 Aug 2022 13:47:58 -0400
Subject: [PATCH] close issue #477 (#478)

---
 src/mathops.jl | 46 +++++++++++++++++++++++-----------------------
 test/tests.jl  |  8 ++++++++
 2 files changed, 31 insertions(+), 23 deletions(-)

diff --git a/src/mathops.jl b/src/mathops.jl
index e6c0f53..1a4172e 100644
--- a/src/mathops.jl
+++ b/src/mathops.jl
@@ -6,31 +6,31 @@
 
 
 
-+(x::SymbolicObject, y::SymbolicObject) = x.__add__(y)
-*(x::SymbolicObject, y::SymbolicObject) = x.__mul__(y)
--(x::SymbolicObject, y::SymbolicObject) = x.__sub__(y)
--(x::SymbolicObject)                    = x.__neg__()
-/(x::SymbolicObject, y::SymbolicObject) = x.__truediv__(y)
-^(x::SymbolicObject, y::SymbolicObject) = x.__pow__(y)
-^(x::SymbolicObject, y::Rational) = x^convert(Sym,y)
-#^(x::SymbolicObject, y::Integer) = x^convert(Sym,y) # no Union{Integer, Rational}, as that has ambiguity
-//(x::SymbolicObject, y::Int) = x / Sym(y)
-//(x::SymbolicObject, y::Rational) = x / Sym(y)
-//(x::SymbolicObject, y::SymbolicObject) = x / y
-
-\(x::SymbolicObject, y::SymbolicObject) = (y'/x')' # ?
++(x::Sym, y::Sym)::Sym = x.__add__(y)
+*(x::Sym, y::Sym)::Sym = x.__mul__(y)
+-(x::Sym, y::Sym)::Sym = x.__sub__(y)
+(-)(x::Sym)::Sym                    = x.__neg__()
+/(x::Sym, y::Sym)::Sym = x.__truediv__(y)
+^(x::Sym, y::Sym)::Sym = x.__pow__(y)
+^(x::Sym, y::Rational) = x^convert(Sym,y)
+#^(x::Sym, y::Integer) = x^convert(Sym,y) # no Union{Integer, Rational}, as that has ambiguity
+//(x::Sym, y::Int) = x / Sym(y)
+//(x::Sym, y::Rational) = x / Sym(y)
+//(x::Sym, y::Sym) = x / y
+
+\(x::Sym, y::Sym) = (y'/x')' # ?
 
 Base.inv(x::Sym) = x.__pow__(Sym(-1))
 
 # special case Boolean; issue   351
 # promotion for Boolean here is to 0 or  1,  not False,  True
-+(x::Bool, y::SymbolicObject) = Sym(Int(x)).__add__(y)
-*(x::Bool, y::SymbolicObject) = Sym(Int(x)).__mul__(y)
--(x::Bool, y::SymbolicObject) = Sym(Int(x)).__sub__(y)
-/(x::Bool, y::SymbolicObject) = Sym(Int(x)).__truediv__(y)
-^(x::Bool, y::SymbolicObject) = Sym(Int(x)).__pow__(y)
-+(x::SymbolicObject, y::Bool) = x.__add__(Int(y))
-*(x::SymbolicObject, y::Bool) = x.__mul__(Int(y))
--(x::SymbolicObject, y::Bool) = x.__sub__(Int(y))
-/(x::SymbolicObject, y::Bool) = x.__truediv__(Int(y))
-^(x::SymbolicObject, y::Bool) = x.__pow__(Int(y))
++(x::Bool, y::Sym)::Sym = Sym(Int(x)).__add__(y)
+*(x::Bool, y::Sym)::Sym = Sym(Int(x)).__mul__(y)
+-(x::Bool, y::Sym)::Sym = Sym(Int(x)).__sub__(y)
+/(x::Bool, y::Sym)::Sym = Sym(Int(x)).__truediv__(y)
+^(x::Bool, y::Sym)::Sym = Sym(Int(x)).__pow__(y)
++(x::Sym, y::Bool)::Sym = x.__add__(Int(y))
+*(x::Sym, y::Bool)::Sym = x.__mul__(Int(y))
+-(x::Sym, y::Bool)::Sym = x.__sub__(Int(y))
+/(x::Sym, y::Bool)::Sym = x.__truediv__(Int(y))
+^(x::Sym, y::Bool)::Sym = x.__pow__(Int(y))
diff --git a/test/tests.jl b/test/tests.jl
index 8424a9c..8f147b3 100644
--- a/test/tests.jl
+++ b/test/tests.jl
@@ -777,6 +777,14 @@ end
     @syms x
     ex = integrate(sqrt(1 + (1/x)^2), (x, 1/sympy.E, sympy.E))
     @test N(ex) ≈ 3.196198513599507
+
+    ## Issue #477 non typestable ops
+    @test Base.Broadcast.combine_eltypes(+, (zero(Sym), zero(Sym))) == Sym
+    @test Base.Broadcast.combine_eltypes(-, (zero(Sym), zero(Sym))) == Sym
+    @test Base.Broadcast.combine_eltypes(*, (zero(Sym), zero(Sym))) == Sym
+    @test Base.Broadcast.combine_eltypes(/, (zero(Sym), zero(Sym))) == Sym
+    @test Base.Broadcast.combine_eltypes(^, (zero(Sym), zero(Sym))) == Sym
+
 end
 
 @testset "generic programming, issue 223" begin