use Requires.jl to define layout for AbstractGraph

Author: hexaeder

Project.toml

@@ -5,6 +5,7 @@ version = "0.4.0"
 [deps]
 GeometryBasics = "5c1252a2-5f33-56bf-86c9-59e7332b4326"
 LinearAlgebra = "37e2e46d-f89d-539d-b4ee-838fcccc9c8e"
+Requires = "ae029012-a4dd-5104-9daa-d747884805df"
 SparseArrays = "2f01184e-e22b-5df5-ae63-d93ebab69eaf"
 
 [compat]

src/NetworkLayout.jl

@@ -1,10 +1,11 @@
 module NetworkLayout
 
-export LayoutIterator, layout
-
 using GeometryBasics
+using Requires
 using LinearAlgebra: norm
 
+export LayoutIterator, layout
+
 """
     AbstractLayout{Dim,Ptype}
 
@@ -66,7 +67,7 @@ struct LayoutIterator{T<:IterativeLayout,M<:AbstractMatrix}
     adj_matrix::M
 end
 
-function layout(alg::IterativeLayout, adj_matrix)
+function layout(alg::IterativeLayout, adj_matrix::AbstractMatrix)
     iter = LayoutIterator(alg, adj_matrix)
     next = Base.iterate(iter)
     pos = next[1]
@@ -78,6 +79,10 @@ function layout(alg::IterativeLayout, adj_matrix)
     return pos
 end
 
+function __init__()
+    @require LightGraphs="093fc24a-ae57-5d10-9952-331d41423f4d" layout(l::AbstractLayout, g::LightGraphs.AbstractGraph) = layout(l, LightGraphs.adjacency_matrix(g))
+end
+
 include("sfdp.jl")
 include("buchheim.jl")
 include("spring.jl")

src/circular.jl

@@ -16,7 +16,7 @@ struct Circular{Ptype} <: AbstractLayout{2,Ptype} end
 
 Circular(; Ptype=Float64) = Circular{Ptype}()
 
-function layout(::Circular{Ptype}, adj_matrix) where {Ptype}
+function layout(::Circular{Ptype}, adj_matrix::AbstractMatrix) where {Ptype}
     if size(adj_matrix, 1) == 1
         return Point{2,Ptype}[Point(0.0, 0.0)]
     else

src/shell.jl

@@ -25,7 +25,7 @@ end
 
 Shell(; Ptype=Float64, nlist=Vector{Int}[]) = Shell{Ptype}(nlist)
 
-function layout(algo::Shell{Ptype}, adj_matrix) where {Ptype}
+function layout(algo::Shell{Ptype}, adj_matrix::AbstractMatrix) where {Ptype}
     if size(adj_matrix, 1) == 1
         return Point{2,Float64}[Point(0.0, 0.0)]
     end

src/spectral.jl

@@ -55,7 +55,7 @@ function compute_laplacian(adj_matrix, node_weights)
     return L, D
 end
 
-function layout(algo::Spectral{Ptype,FT}, adj_matrix) where {Ptype,FT}
+function layout(algo::Spectral{Ptype,FT}, adj_matrix::AbstractMatrix) where {Ptype,FT}
     # try to use user provided nodeweights
     nodeweights = if length(algo.nodeweights) == size(adj_matrix, 1)
         algo.nodeweights

test/runtests.jl

@@ -274,4 +274,11 @@ jagmesh_adj = jagmesh()
             @test positions == Point2.([(1, 0), (2, 0), (0, -1), (2, -1)])
         end
     end
+
+    @testset "test LightGraphs glue code" begin
+        println("Test LightGraphs glue code")
+        g = complete_graph(10)
+        pos = Spring()(g)
+        @test pos isa Vector{Point{2,Float64}}
+    end
 end