Fix ambiguities in similar and blockreshape (#99)

Author: mtfishman

Project.toml

@@ -1,7 +1,7 @@
 name = "BlockSparseArrays"
 uuid = "2c9a651f-6452-4ace-a6ac-809f4280fbb4"
 authors = ["ITensor developers <[email protected]> and contributors"]
-version = "0.4.2"
+version = "0.4.3"
 
 [deps]
 Adapt = "79e6a3ab-5dfb-504d-930d-738a2a938a0e"

src/BlockArraysExtensions/BlockArraysExtensions.jl

@@ -263,17 +263,20 @@ function blocks_to_cartesianindices(d::Dictionary{<:Block})
   return Dictionary(blocks_to_cartesianindices(eachindex(d)), d)
 end
 
-function blockreshape(a::AbstractArray, dims::Tuple{Vararg{Vector{Int}}})
+function blockreshape(a::AbstractArray, dims::Tuple{Vector{Int},Vararg{Vector{Int}}})
   return blockreshape(a, blockedrange.(dims))
 end
-
-function blockreshape(a::AbstractArray, dims::Vararg{Vector{Int}})
-  return blockreshape(a, dims)
+function blockreshape(a::AbstractArray, dim1::Vector{Int}, dim_rest::Vararg{Vector{Int}})
+  return blockreshape(a, (dim1, dim_rest...))
+end
+# Fix ambiguity error.
+function blockreshape(a::AbstractArray)
+  return blockreshape(a, ())
 end
 
 tuple_oneto(n) = ntuple(identity, n)
 
-function blockreshape(a::AbstractArray, axes::Tuple{Vararg{AbstractUnitRange}})
+function _blockreshape(a::AbstractArray, axes::Tuple{Vararg{AbstractUnitRange}})
   reshaped_blocks_a = reshape(blocks(a), blocklength.(axes))
   reshaped_a = similar(a, axes)
   for I in eachstoredindex(reshaped_blocks_a)
@@ -284,8 +287,20 @@ function blockreshape(a::AbstractArray, axes::Tuple{Vararg{AbstractUnitRange}})
   return reshaped_a
 end
 
-function blockreshape(a::AbstractArray, axes::Vararg{AbstractUnitRange})
-  return blockreshape(a, axes)
+function blockreshape(
+  a::AbstractArray, axes::Tuple{AbstractUnitRange,Vararg{AbstractUnitRange}}
+)
+  return _blockreshape(a, axes)
+end
+# Fix ambiguity error.
+function blockreshape(a::AbstractArray, axes::Tuple{})
+  return _blockreshape(a, axes)
+end
+
+function blockreshape(
+  a::AbstractArray, axis1::AbstractUnitRange, axes_rest::Vararg{AbstractUnitRange}
+)
+  return blockreshape(a, (axis1, axes_rest...))
 end
 
 function cartesianindices(axes::Tuple, b::Block)

src/abstractblocksparsearray/wrappedabstractblocksparsearray.jl

@@ -232,6 +232,18 @@ end
 )
   return blocksparse_similar(a, elt, axes)
 end
+# Fix ambiguity error when non-blocked ranges are passed.
+@interface ::AbstractBlockSparseArrayInterface function Base.similar(
+  a::AbstractArray, elt::Type, axes::Tuple{Base.OneTo,Vararg{Base.OneTo}}
+)
+  return blocksparse_similar(a, elt, axes)
+end
+# Fix ambiguity error when empty axes are passed.
+@interface ::AbstractBlockSparseArrayInterface function Base.similar(
+  a::AbstractArray, elt::Type, axes::Tuple{}
+)
+  return blocksparse_similar(a, elt, axes)
+end
 @interface ::AbstractBlockSparseArrayInterface function Base.similar(
   a::Type{<:AbstractArray}, elt::Type, axes::Tuple{Vararg{Int}}
 )

test/test_basics.jl

@@ -405,6 +405,13 @@ arrayts = (Array, JLArray)
     @test size(b) == size(a)
     @test blocksize(b) == blocksize(a)
 
+    # Regression test for https://github.com/ITensor/BlockSparseArrays.jl/issues/98
+    a = dev(BlockSparseArray{elt}(undef))
+    b = similar(a, Float64, (Base.OneTo(1),))
+    @test b isa BlockSparseVector{Float64}
+    @test size(b) == (1,)
+    @test blocksize(b) == (1,)
+
     a = dev(BlockSparseArray{elt}(undef, [2, 3], [3, 4]))
     b = @view a[[Block(2), Block(1)], [Block(2), Block(1)]]
     c = @view b[Block(1, 1)]
@@ -1126,6 +1133,15 @@ arrayts = (Array, JLArray)
     @test reshape(a[Block(2, 1)], 8) == b[Block(2)]
     @test blockstoredlength(b) == 2
     @test storedlength(b) == 17
+
+    # Zero-dimensional limit (check for ambiguity errors).
+    # Regression test for https://github.com/ITensor/BlockSparseArrays.jl/issues/98.
+    a = dev(BlockSparseArray{elt}(undef, ()))
+    a[Block()] = dev(randn(elt, ()))
+    b = blockreshape(a)
+    @test a[Block()] == b[Block()]
+    @test blockstoredlength(b) == 1
+    @test storedlength(b) == 1
   end
   @testset "show" begin
     vectort_elt = arrayt{elt,1}

test/test_tensoralgebraext.jl

@@ -59,14 +59,12 @@ const elts = (Float32, Float64, Complex{Float32}, Complex{Float64})
     @test a_dest ≈ a_dest_dense
 
     # vector vector
-    @test_broken a_dest, dimnames_dest = contract(a3, (1, 2), a3, (2, 1))
-    #=
+    a_dest, dimnames_dest = contract(a3, (1, 2), a3, (2, 1))
     a_dest_dense, dimnames_dest_dense = contract(a3_dense, (1, 2), a3_dense, (2, 1))
     @test dimnames_dest == dimnames_dest_dense
     @test size(a_dest) == size(a_dest_dense)
     @test a_dest isa BlockSparseArray{elt,0}
     @test a_dest ≈ a_dest_dense
-    =#
 
     # outer product
     a_dest_dense, dimnames_dest_dense = contract(a3_dense, (1, 2), a3_dense, (3, 4))