Move visualize overloads to ITensorVisualizationBase extension (#367)

## Summary

- Adds `ITensorNetworksITensorVisualizationBaseExt`, a new package
extension keyed on `ITensorVisualizationBase`, holding the
`visualize(::AbstractITensorNetwork, ...)` overload that previously
lived in `src/abstractitensornetwork.jl`.
- Drops `src/visualize.jl` entirely. The two methods it held (overloads
of `visualize` on `AbstractNamedGraph` and `AbstractDataGraph`, which
were type piracy from here) move upstream into the packages that own
those types: see
[ITensor/NamedGraphs.jl#166](ITensor/NamedGraphs.jl#166)
and
[ITensor/DataGraphs.jl#119](ITensor/DataGraphs.jl#119).
- Bumps `[compat]` floors to `NamedGraphs = "0.11.1"` and `DataGraphs =
"0.4.1"` to ensure the upstream extensions are present.
- The extensions are keyed on the registered standalone
`ITensorVisualizationBase` package. The methods overload
`ITensorVisualizationBase.visualize`, which shares a binding with
`ITensors.ITensorVisualizationCore.visualize` (the in-tree submodule),
so rendering backends pick them up.

Adds `test/test_itensorvisualizationbase_ext.jl` covering the new
method.

Co-authored-by: Claude Opus 4.7 (1M context) <noreply@anthropic.com>

Author: mtfishman

Project.toml

@@ -29,26 +29,29 @@ StructWalk = "31cdf514-beb7-4750-89db-dda9d2eb8d3d"
 TupleTools = "9d95972d-f1c8-5527-a6e0-b4b365fa01f6"
 
 [weakdeps]
+ITensorVisualizationBase = "cd2553d2-8bef-4d93-8a38-c62f17d5ad23"
 OMEinsumContractionOrders = "6f22d1fd-8eed-4bb7-9776-e7d684900715"
 TensorOperations = "6aa20fa7-93e2-5fca-9bc0-fbd0db3c71a2"
 
 [extensions]
+ITensorNetworksITensorVisualizationBaseExt = "ITensorVisualizationBase"
 ITensorNetworksOMEinsumContractionOrdersExt = "OMEinsumContractionOrders"
 ITensorNetworksTensorOperationsExt = "TensorOperations"
 
 [compat]
 Accessors = "0.1.42"
 Adapt = "4"
-DataGraphs = "0.4"
+DataGraphs = "0.4.1"
 Dictionaries = "0.4"
 DocStringExtensions = "0.9"
 Graphs = "1.8"
+ITensorVisualizationBase = "0.1"
 ITensors = "0.7, 0.8, 0.9"
 IsApprox = "0.1, 1, 2"
 KrylovKit = "0.6, 0.7, 0.8, 0.9, 0.10"
 MacroTools = "0.5"
 NDTensors = "0.3, 0.4"
-NamedGraphs = "0.11"
+NamedGraphs = "0.11.1"
 OMEinsumContractionOrders = "0.8.3, 0.9, 1"
 SimpleTraits = "0.9"
 SplitApplyCombine = "1.2"

ext/ITensorNetworksITensorVisualizationBaseExt/ITensorNetworksITensorVisualizationBaseExt.jl

@@ -0,0 +1,22 @@
+module ITensorNetworksITensorVisualizationBaseExt
+
+using Graphs: vertices
+using ITensorNetworks: AbstractITensorNetwork
+using ITensorVisualizationBase: ITensorVisualizationBase
+
+function ITensorVisualizationBase.visualize(
+        tn::AbstractITensorNetwork,
+        args...;
+        vertex_labels_prefix = nothing,
+        vertex_labels = nothing,
+        kwargs...
+    )
+    if !isnothing(vertex_labels_prefix)
+        vertex_labels = [vertex_labels_prefix * string(v) for v in vertices(tn)]
+    end
+    return ITensorVisualizationBase.visualize(
+        [tn[v] for v in vertices(tn)], args...; vertex_labels, kwargs...
+    )
+end
+
+end

src/ITensorNetworks.jl

@@ -1,6 +1,5 @@
 module ITensorNetworks
 
-include("visualize.jl")
 include("abstractindsnetwork.jl")
 include("indextags.jl")
 include("indsnetwork.jl")

src/abstractitensornetwork.jl

@@ -540,24 +540,6 @@ end
 
 Base.show(io::IO, graph::AbstractITensorNetwork) = show(io, MIME"text/plain"(), graph)
 
-# TODO: Move to an `ITensorNetworksVisualizationInterfaceExt`
-# package extension (and define a `VisualizationInterface` package
-# based on `ITensorVisualizationCore`.).
-using ITensors.ITensorVisualizationCore: ITensorVisualizationCore, visualize
-function ITensorVisualizationCore.visualize(
-        tn::AbstractITensorNetwork,
-        args...;
-        vertex_labels_prefix = nothing,
-        vertex_labels = nothing,
-        kwargs...
-    )
-    if !isnothing(vertex_labels_prefix)
-        vertex_labels = [vertex_labels_prefix * string(v) for v in vertices(tn)]
-    end
-    # TODO: Use `tokenize_vertex`.
-    return visualize([tn[v] for v in vertices(tn)], args...; vertex_labels, kwargs...)
-end
-
 #
 # Link dimensions
 #

src/visualize.jl

@@ -10,6 +10,7 @@ GraphsFlows = "06909019-6f44-4949-96fc-b9d9aaa02889"
 ITensorMPS = "0d1a4710-d33b-49a5-8f18-73bdf49b47e2"
 ITensorNetworks = "2919e153-833c-4bdc-8836-1ea460a35fc7"
 ITensorPkgSkeleton = "3d388ab1-018a-49f4-ae50-18094d5f71ea"
+ITensorVisualizationBase = "cd2553d2-8bef-4d93-8a38-c62f17d5ad23"
 ITensors = "9136182c-28ba-11e9-034c-db9fb085ebd5"
 KrylovKit = "0b1a1467-8014-51b9-945f-bf0ae24f4b77"
 LinearAlgebra = "37e2e46d-f89d-539d-b4ee-838fcccc9c8e"
@@ -35,20 +36,21 @@ path = ".."
 Adapt = "4.3"
 Aqua = "0.8.11"
 Compat = "4.16"
-DataGraphs = "0.4"
+DataGraphs = "0.4.1"
 Dictionaries = "0.4.4"
 Glob = "1.3.1"
 Graphs = "1.12"
 GraphsFlows = "0.1.1"
 ITensorMPS = "0.3.6, 0.4"
 ITensorNetworks = "0.22"
 ITensorPkgSkeleton = "0.3.42"
+ITensorVisualizationBase = "0.1"
 ITensors = "0.7, 0.8, 0.9"
 KrylovKit = "0.8, 0.9, 0.10"
 LinearAlgebra = "1.10"
 Metis = "1.5"
 NDTensors = "0.3, 0.4"
-NamedGraphs = "0.11"
+NamedGraphs = "0.11.1"
 OMEinsumContractionOrders = "0.9.5, 1"
 Pkg = "1.10"
 Random = "1.10"

test/Project.toml

@@ -0,0 +1,12 @@
+using ITensorNetworks: AbstractITensorNetwork, ITensorNetwork
+using ITensorVisualizationBase: ITensorVisualizationBase
+using ITensors: ITensor, Index
+using Test: @test, @testset
+
+@testset "ITensorNetworksITensorVisualizationBaseExt" begin
+    i, j, k = Index(2, "i"), Index(2, "j"), Index(2, "k")
+    tn = ITensorNetwork([ITensor(i, j), ITensor(j, k)])
+    @test hasmethod(ITensorVisualizationBase.visualize, Tuple{AbstractITensorNetwork})
+    @test isnothing(ITensorVisualizationBase.visualize(tn))
+    @test isnothing(ITensorVisualizationBase.visualize(tn; vertex_labels_prefix = "v"))
+end