From 4e43811ea3385a3d7abaab8ca4796bd03fe50dec Mon Sep 17 00:00:00 2001
From: Marek Kaluba <kalmar@amu.edu.pl>
Date: Fri, 17 Mar 2023 15:53:36 +0100
Subject: [PATCH] fix a nasty bug with negatives in ConstraintMatrix

---
 src/constraint_matrix.jl     | 13 +++++++++----
 test/constratint_matrices.jl | 14 +++++++++++---
 2 files changed, 20 insertions(+), 7 deletions(-)

diff --git a/src/constraint_matrix.jl b/src/constraint_matrix.jl
index 8fbd36a..5734837 100644
--- a/src/constraint_matrix.jl
+++ b/src/constraint_matrix.jl
@@ -50,10 +50,15 @@ ConstraintMatrix(nzeros::AbstractArray{<:Integer}, n, m, val::T) where {T} =
 
 Base.size(cm::ConstraintMatrix) = cm.size
 
-__get_positive(cm::ConstraintMatrix, idx::Integer) =
-    convert(eltype(cm), cm.val * length(searchsorted(cm.pos, idx)))
-__get_negative(cm::ConstraintMatrix, idx::Integer) =
-    convert(eltype(cm), cm.val * length(searchsorted(cm.neg, idx)))
+function __get_positive(cm::ConstraintMatrix, idx::Integer)
+    return convert(eltype(cm), cm.val * length(searchsorted(cm.pos, idx)))
+end
+function __get_negative(cm::ConstraintMatrix, idx::Integer)
+    return convert(
+        eltype(cm),
+        cm.val * length(searchsorted(cm.neg, idx; rev = true)),
+    )
+end
 
 Base.@propagate_inbounds function Base.getindex(
     cm::ConstraintMatrix,
diff --git a/test/constratint_matrices.jl b/test/constratint_matrices.jl
index afdee61..1d04876 100644
--- a/test/constratint_matrices.jl
+++ b/test/constratint_matrices.jl
@@ -1,12 +1,17 @@
 @testset "ConstraintMatrix" begin
-    @test PropertyT.ConstraintMatrix{Float64}([-1, 2, -1, 1, 4, 2, 6], 3, 2, π) isa AbstractMatrix
+    @test PropertyT.ConstraintMatrix{Float64}(
+        [-1, 2, -1, 1, 4, 2, 6],
+        3,
+        2,
+        π,
+    ) isa AbstractMatrix
 
     cm = PropertyT.ConstraintMatrix{Float64}([-1, 2, -1, 1, 4, 2, 6], 3, 2, π)
 
     @test cm == Float64[
         -π π
-        2π 0.0
-        0.0 π
+        2π 0
+        0 π
     ]
 
     @test collect(PropertyT.nzpairs(cm)) == [
@@ -18,4 +23,7 @@
         1 => -3.141592653589793
         1 => -3.141592653589793
     ]
+
+    @test PropertyT.ConstraintMatrix{Float64}([-9:-1; 1:9], 3, 3, 1.0) ==
+          zeros(3, 3)
 end