Avoid original meshes being modified when merging

Author: AleMorales

src/Mesh/Mesh.jl

@@ -174,9 +174,9 @@ julia> add_property!(r, :absorbed_PAR, [0.0, 0.0]);
 function add_property!(m::Mesh, prop::Symbol, data, nt = ntriangles(m))
     # Check if the data is an array and if not convert it to an array with length nt
     vecdata = data isa AbstractVector ? data : fill(data, nt)
-    # Create new property if the one being added does not exist
+    # Create new property if the one being added does not exist (make sure to copy)
     if !haskey(properties(m), prop)
-        properties(m)[prop] = vecdata
+        properties(m)[prop] = copy(vecdata)
     # Otherwise add to existing property
     else
         add_property!(properties(m), prop, vecdata)
@@ -207,7 +207,7 @@ julia> m = Mesh([e,r]);
 function Mesh(meshes::Vector{<:Mesh})
     @assert !isempty(meshes) "At least one mesh must be provided"
     @inbounds verts = copy(vertices(meshes[1]))
-    @inbounds props = properties(meshes[1])
+    @inbounds props = copy(properties(meshes[1]))
     if length(meshes) > 1
         @inbounds for i in 2:length(meshes)
             append!(verts, vertices(meshes[i]))

test/test_properties.jl

@@ -19,18 +19,29 @@ e = PGP.Ellipse()
 t = PGP.Triangle()
 
 PGP.add_property!(r, :prop, D.bar())
-eltype(PGP.properties(r)[:prop]) == D.bar
+@test eltype(PGP.properties(r)[:prop]) == D.bar
 PGP.add!(r, e, prop = D.foo())
-eltype(PGP.properties(r)[:prop]) == Union{D.bar, D.foo}
+@test eltype(PGP.properties(r)[:prop]) == Union{D.bar, D.foo}
 PGP.add!(r, t, prop = D.oomp())
-eltype(PGP.properties(r)[:prop]) == Union{D.bar, D.foo, D.oomp}
+@test eltype(PGP.properties(r)[:prop]) == Union{D.bar, D.foo, D.oomp}
 
 
-# Merging properties of two meshes
+# Merging meshes
+# Make sure property unions are created
 PGP.add_property!(e, :prop, D.foo())
 PGP.add_property!(t, :prop, D.bar())
 m = PGP.Mesh([t, e])
-eltype(PGP.properties(m)[:prop]) == Union{D.bar, D.foo}
-
+@test eltype(PGP.properties(m)[:prop]) == Union{D.bar, D.foo}
+@test eltype(PGP.properties(e)[:prop]) == D.foo
+@test eltype(PGP.properties(t)[:prop]) == D.bar
+# Make sure original meshes are not modified
+l1 = length(PGP.properties(e)[:prop])
+l2 = length(PGP.properties(t)[:prop])
+l3 = length(PGP.properties(m)[:prop])
+@test l1 + l2 == l3
+nv1 = PGP.nvertices(e)
+nv2 = PGP.nvertices(t)
+nv3 = PGP.nvertices(m)
+@test nv1 + nv2 == nv3
 
 end