Support ComponentArrays.jl in Krylov.jl (#859)

* Update krylov_utils.jl

* Add a test for ComponentArrays.jl

* Fix .buildkite/pipeline.yml

* Update component_arrays.jl

.buildkite/pipeline.yml

@@ -2,7 +2,7 @@ steps:
   - label: "Nvidia GPUs -- CUDA.jl"
     plugins:
       - JuliaCI/julia#v1:
-          version: 1.9
+          version: "1.10"
     agents:
       queue: "juliagpu"
       cuda: "*"
@@ -22,7 +22,7 @@ steps:
   - label: "AMD GPUs -- AMDGPU.jl"
     plugins:
       - JuliaCI/julia#v1:
-          version: 1.9
+          version: "1.10"
     agents:
       queue: "juliagpu"
       rocm: "*"
@@ -43,7 +43,7 @@ steps:
   - label: "Intel GPUs -- oneAPI.jl"
     plugins:
       - JuliaCI/julia#v1:
-          version: 1.9
+          version: "1.10"
     agents:
       queue: "juliagpu"
       intel: "*"
@@ -58,7 +58,7 @@ steps:
   - label: "Apple M1 GPUs -- Metal.jl"
     plugins:
       - JuliaCI/julia#v1:
-          version: 1.9
+          version: "1.10"
     agents:
       queue: "juliaecosystem"
       os: "macos"
@@ -74,13 +74,27 @@ steps:
   - label: "CPUs -- StaticArrays.jl"
     plugins:
       - JuliaCI/julia#v1:
-          version: 1.9
+          version: "1.10"
     agents:
       queue: "juliaecosystem"
     command: |
       julia --color=yes --project -e '
         using Pkg
         Pkg.add("StaticArrays")
         Pkg.instantiate()
-        include("test/test_extensions.jl")'
+        include("test/cpu/static_arrays.jl")'
+    timeout_in_minutes: 30
+
+  - label: "CPUs -- ComponentArrays.jl"
+    plugins:
+      - JuliaCI/julia#v1:
+          version: "1.10"
+    agents:
+      queue: "juliaecosystem"
+    command: |
+      julia --color=yes --project -e '
+        using Pkg
+        Pkg.add("ComponentArrays")
+        Pkg.instantiate()
+        include("test/cpu/component_arrays.jl")'
     timeout_in_minutes: 30

.cirrus.yml

@@ -14,7 +14,7 @@ task:
         - JULIA_VERSION: 1
     - name: MacOS M1
       macos_instance:
-        image: ghcr.io/cirruslabs/macos-monterey-base:latest
+        image: ghcr.io/cirruslabs/macos-ventura-base:latest
       env:
         - JULIA_VERSION: 1
   install_script: |

.github/workflows/ci.yml

@@ -14,7 +14,7 @@ jobs:
       fail-fast: false
       matrix:
         version: ['1.6', '1']
-        os: [ubuntu-latest, macOS-latest, windows-latest]
+        os: [ubuntu-latest, macos-13, windows-latest]
         arch: [x64]
         allow_failure: [false]
         include:
@@ -23,15 +23,15 @@ jobs:
             arch: x64
             allow_failure: true
           - version: 'nightly'
-            os: macOS-latest
+            os: macos-13
             arch: x64
             allow_failure: true
           - version: 'nightly'
             os: windows-latest
             arch: x64
             allow_failure: true
     steps:
-      - uses: actions/checkout@v3
+      - uses: actions/checkout@v4
       - uses: julia-actions/setup-julia@v2
         with:
           version: ${{ matrix.version }}

src/krylov_utils.jl

@@ -206,17 +206,22 @@ Return the most relevant storage type `S` based on the type of `v`.
 function ktypeof end
 
 function ktypeof(v::S) where S <: DenseVector
-  return S
+  if S.name.name == :ComponentArray
+    T = eltype(S)
+    return Vector{T}
+  else
+    return S
+  end
 end
 
 function ktypeof(v::S) where S <: DenseMatrix
   return S
 end
 
 function ktypeof(v::S) where S <: AbstractVector
-  if S.name.name == :Zeros || S.name.name == :Ones || S.name.name == :SArray || S.name.name == :MArray || S.name.name == :SizedArray || S.name.name == :FieldArray || S.name.name == :ComponentArray
+  if S.name.name == :Zeros || S.name.name == :Ones || S.name.name == :SArray || S.name.name == :MArray || S.name.name == :SizedArray || S.name.name == :FieldArray
     T = eltype(S)
-    return Vector{T}  # FillArrays, StaticArrays, ComponentArrays
+    return Vector{T}  # FillArrays, StaticArrays
   else
     return S  # BlockArrays, PartitionedArrays, etc...
   end

test/cpu/component_arrays.jl

@@ -0,0 +1,15 @@
+using LinearAlgebra, SparseArrays, Test
+using Krylov, ComponentArrays
+
+@testset "ComponentArrays" begin
+  n = 5
+
+  for T in (Float32, Float64)
+    A = rand(T, n, n)
+
+    b = ComponentVector{T}(a=[1, 2, 3], b=[4, 5])
+    @test Krylov.ktypeof(b) == Vector{T}
+    x, stats = gmres(A, b)
+    @test stats.solved
+  end
+end