From 04d71a7f7a95c5fc1817845d3766a7fc3337aa6c Mon Sep 17 00:00:00 2001
From: mtfishman <mfishman@flatironinstitute.org>
Date: Thu, 30 Jan 2025 12:53:57 -0500
Subject: [PATCH] Generalize Index constructor to allow ranges, define `hastag`

---
 Project.toml        |  2 +-
 src/index.jl        | 11 ++++++++++-
 test/test_basics.jl | 23 ++++++++++++++++++-----
 3 files changed, 29 insertions(+), 7 deletions(-)

diff --git a/Project.toml b/Project.toml
index b25b39c..b1326a1 100644
--- a/Project.toml
+++ b/Project.toml
@@ -1,7 +1,7 @@
 name = "ITensorBase"
 uuid = "4795dd04-0d67-49bb-8f44-b89c448a1dc7"
 authors = ["ITensor developers <support@itensor.org> and contributors"]
-version = "0.1.12"
+version = "0.1.13"
 
 [deps]
 Accessors = "7d9f7c33-5ae7-4f3b-8dc6-eff91059b697"
diff --git a/src/index.jl b/src/index.jl
index 8b0f6a8..4fd152e 100644
--- a/src/index.jl
+++ b/src/index.jl
@@ -25,6 +25,8 @@ plev(n::IndexName) = n.plev
 
 settags(n::IndexName, tags) = @set n.tags = tags
 
+hastag(n::IndexName, tagname::String) = haskey(tags(n), tagname)
+
 gettag(n::IndexName, tagname::String) = tags(n)[tagname]
 gettag(n::IndexName, tagname::String, default) = get(tags(n), tagname, default)
 function settag(n::IndexName, tagname::String, tag::String)
@@ -69,8 +71,12 @@ struct Index{T,Value<:AbstractUnitRange{T}} <: AbstractNamedUnitRange{T,Value,In
   name::IndexName
 end
 
+function Index(r::AbstractUnitRange; kwargs...)
+  return Index(r, IndexName(; kwargs...))
+end
+
 function Index(length::Int; kwargs...)
-  return Index(Base.OneTo(length), IndexName(; kwargs...))
+  return Index(Base.OneTo(length); kwargs...)
 end
 
 # TODO: Define for `NamedDimsArrays.NamedViewIndex`.
@@ -78,6 +84,9 @@ id(i::Index) = id(name(i))
 tags(i::Index) = tags(name(i))
 plev(i::Index) = plev(name(i))
 
+# TODO: Define for `NamedDimsArrays.NamedViewIndex`.
+hastag(i::Index, tagname::String) = hastag(name(i), tagname)
+
 # TODO: Define for `NamedDimsArrays.NamedViewIndex`.
 gettag(i::Index, tagname::String) = gettag(name(i), tagname)
 gettag(i::Index, tagname::String, default) = gettag(name(i), tagname, default)
diff --git a/test/test_basics.jl b/test/test_basics.jl
index d1c0ea2..c2c0e1b 100644
--- a/test/test_basics.jl
+++ b/test/test_basics.jl
@@ -1,6 +1,7 @@
-using ITensorBase: ITensorBase, ITensor, Index, gettag, inds, plev, prime, settag, unsettag
+using ITensorBase:
+  ITensorBase, ITensor, Index, gettag, hastag, inds, plev, prime, settag, tags, unsettag
 using DiagonalArrays: δ, delta, diagview
-using NamedDimsArrays: unname
+using NamedDimsArrays: dename, name, named
 using Test: @test, @test_broken, @testset
 
 @testset "ITensorBase" begin
@@ -8,19 +9,31 @@ using Test: @test, @test_broken, @testset
     i, j = Index.((2, 2))
     x = randn(2, 2)
     for a in (ITensor(x, i, j), ITensor(x, (i, j)))
-      @test unname(a) == x
+      @test dename(a) == x
       @test plev(i) == 0
       @test plev(prime(i)) == 1
+      @test length(tags(i)) == 0
       a′ = prime(a)
-      @test unname(a′) == x
+      @test dename(a′) == x
       @test issetequal(inds(a′), (prime(i), prime(j)))
     end
 
     i = Index(2)
     i = settag(i, "X", "x")
+    @test hastag(i, "X")
+    @test !hastag(i, "Y")
     @test gettag(i, "X") == "x"
     i = unsettag(i, "X")
     @test isnothing(gettag(i, "X", nothing))
+    @test !hastag(i, "X")
+    @test !hastag(i, "Y")
+
+    i = Index(Base.OneTo(2))
+    @test length(i) == named(2, name(i))
+    @test dename(length(i)) == 2
+    @test dename(i) == 1:2
+    @test plev(i) == 0
+    @test length(tags(i)) == 0
   end
   @testset "delta" begin
     i, j = Index.((2, 2))
@@ -37,7 +50,7 @@ using Test: @test, @test_broken, @testset
       @test eltype(a) === Bool
       # TODO: Fix this.
       @test_broken diagview(a)
-      @test diagview(unname(a)) == ones(2)
+      @test diagview(dename(a)) == ones(2)
     end
   end
 end