From 286a048e8602219b97be7f14f289b75ba3387040 Mon Sep 17 00:00:00 2001
From: Matt Fishman <mtfishman@users.noreply.github.com>
Date: Thu, 2 May 2024 07:42:07 -0400
Subject: [PATCH] Fix `ProjTTN` constructor for mixed input vertex types (#165)

---
 Project.toml                                  |  2 +-
 src/treetensornetworks/projttns/projttn.jl    | 16 +++++++++++++++-
 test/test_treetensornetworks/Project.toml     |  2 ++
 test/test_treetensornetworks/test_position.jl | 15 ++++++++++++---
 4 files changed, 30 insertions(+), 5 deletions(-)

diff --git a/Project.toml b/Project.toml
index bd434c6b..fd6518f2 100644
--- a/Project.toml
+++ b/Project.toml
@@ -1,7 +1,7 @@
 name = "ITensorNetworks"
 uuid = "2919e153-833c-4bdc-8836-1ea460a35fc7"
 authors = ["Matthew Fishman <mfishman@flatironinstitute.org> and contributors"]
-version = "0.10.1"
+version = "0.10.2"
 
 [deps]
 AbstractTrees = "1520ce14-60c1-5f80-bbc7-55ef81b5835c"
diff --git a/src/treetensornetworks/projttns/projttn.jl b/src/treetensornetworks/projttns/projttn.jl
index dcf10bbb..f4e1f200 100644
--- a/src/treetensornetworks/projttns/projttn.jl
+++ b/src/treetensornetworks/projttns/projttn.jl
@@ -12,10 +12,24 @@ struct ProjTTN{V,Pos<:Union{Indices{V},NamedEdge{V}}} <: AbstractProjTTN{V}
   pos::Pos
   operator::TTN{V}
   environments::Dictionary{NamedEdge{V},ITensor}
+  global function _ProjTTN(pos, operator::TTN, environments::Dictionary)
+    return new{vertextype(operator),Indices{vertextype(operator)}}(
+      Indices{vertextype(operator)}(pos),
+      operator,
+      convert(Dictionary{NamedEdge{vertextype(operator)},ITensor}, environments),
+    )
+  end
+  global function _ProjTTN(pos::NamedEdge, operator::TTN, environments::Dictionary)
+    return new{vertextype(operator),NamedEdge{vertextype(operator)}}(
+      convert(NamedEdge{vertextype(operator)}, pos),
+      operator,
+      convert(Dictionary{NamedEdge{vertextype(operator)},ITensor}, environments),
+    )
+  end
 end
 
 function ProjTTN(pos, operator::TTN, environments::Dictionary)
-  return ProjTTN(Indices(pos), operator, environments)
+  return _ProjTTN(pos, operator, environments)
 end
 
 function ProjTTN(operator::TTN)
diff --git a/test/test_treetensornetworks/Project.toml b/test/test_treetensornetworks/Project.toml
index bc880f8b..05ed66f7 100644
--- a/test/test_treetensornetworks/Project.toml
+++ b/test/test_treetensornetworks/Project.toml
@@ -1,4 +1,6 @@
 [deps]
+Dictionaries = "85a47980-9c8c-11e8-2b9f-f7ca1fa99fb4"
 Graphs = "86223c79-3864-5bf0-83f7-82e725a168b6"
 ITensorNetworks = "2919e153-833c-4bdc-8836-1ea460a35fc7"
+ITensors = "9136182c-28ba-11e9-034c-db9fb085ebd5"
 NamedGraphs = "678767b0-92e7-4007-89e4-4527a8725b19"
diff --git a/test/test_treetensornetworks/test_position.jl b/test/test_treetensornetworks/test_position.jl
index 6e5fdd44..86916881 100644
--- a/test/test_treetensornetworks/test_position.jl
+++ b/test/test_treetensornetworks/test_position.jl
@@ -1,9 +1,11 @@
 @eval module $(gensym())
+using Dictionaries: Dictionary, Indices
 using Graphs: vertices
-using ITensors: ITensors
-using ITensorNetworks: ProjTTN, ttn, environments, position, siteinds
+using ITensors: ITensors, ITensor
+using ITensorNetworks: ITensorNetwork, ProjTTN, ttn, environments, position, siteinds
 using ITensorNetworks.ModelHamiltonians: ModelHamiltonians
-using NamedGraphs.NamedGraphGenerators: named_comb_tree
+using NamedGraphs: NamedEdge
+using NamedGraphs.NamedGraphGenerators: named_comb_tree, named_path_graph
 using Test: @test, @testset
 
 @testset "ProjTTN position" begin
@@ -47,4 +49,11 @@ using Test: @test, @testset
     ITensors.disable_auto_fermion()
   end
 end
+@testset "ProjTTN construction regression test" begin
+  pos = Indices{Tuple{String,Int}}()
+  g = named_path_graph(2)
+  operator = ttn(ITensorNetwork{Any}(g))
+  environments = Dictionary{NamedEdge{Any},ITensor}()
+  @test ProjTTN(pos, operator, environments) isa ProjTTN{Any,Indices{Any}}
+end
 end