From 4c7deac5cfc383546dd0e2c8d4aa7967a57eae82 Mon Sep 17 00:00:00 2001
From: Tommy Hofmann <thofma@gmail.com>
Date: Fri, 2 Feb 2024 15:26:13 +0100
Subject: [PATCH] fix: make dot work again

---
 src/AbstractAlgebra.jl |  1 +
 src/Rings.jl           | 12 ++++++++++++
 test/Rings-test.jl     |  9 +++++++++
 3 files changed, 22 insertions(+)

diff --git a/src/AbstractAlgebra.jl b/src/AbstractAlgebra.jl
index 70f18bd604..d91016ed4e 100644
--- a/src/AbstractAlgebra.jl
+++ b/src/AbstractAlgebra.jl
@@ -29,6 +29,7 @@ const import_exclude = [:import_exclude, :QQ, :ZZ,
 # They should not be imported/exported anywhere else.
 
 import LinearAlgebra: det
+import LinearAlgebra: dot
 import LinearAlgebra: hessenberg
 import LinearAlgebra: ishermitian
 import LinearAlgebra: issymmetric
diff --git a/src/Rings.jl b/src/Rings.jl
index cc02013e26..282dc06245 100644
--- a/src/Rings.jl
+++ b/src/Rings.jl
@@ -174,3 +174,15 @@ is_finite(F::FinField) = true
 is_finite(F::Field) = characteristic(F) != 0 && throw(NotImplementedError(:is_finite, F))
 
 characteristic(F::NumField) = 0
+
+################################################################################
+#
+#   Dot
+#
+################################################################################
+
+dot(x::RingElem, y::RingElem) = x * y
+
+dot(x::RingElem, y::Union{Integer, Rational, AbstractFloat}) = x * y
+
+dot(x::Union{Integer, Rational, AbstractFloat}, y::RingElem) = x * y
diff --git a/test/Rings-test.jl b/test/Rings-test.jl
index a790decd07..c3369b541c 100644
--- a/test/Rings-test.jl
+++ b/test/Rings-test.jl
@@ -67,3 +67,12 @@ end
   @test is_finite(GF(2))
   @test !is_finite(QQ)
 end
+
+@testset "dot" begin
+  Qx, x  = QQ["x"]
+  @test dot([x, x^2], [1, 1]) == x + x^2
+  @test dot([x, x^2], Rational{BigInt}[1, 1]) == x + x^2
+  @test dot([1, 1], [x, x^2]) == x + x^2
+  @test dot(Rational{BigInt}[1, 1], [x, x^2]) == x + x^2
+  @test dot([x], [x^2]) == x^3
+end