more setters: propertynames & ustrip (#135)

* set(ustrip)
* set(propertynames)

Author: aplavin

Project.toml

@@ -20,12 +20,14 @@ IntervalSets = "8197267c-284f-5f27-9208-e0e47529a953"
 Requires = "ae029012-a4dd-5104-9daa-d747884805df"
 StaticArrays = "90137ffa-7385-5640-81b9-e52037218182"
 StructArrays = "09ab397b-f2b6-538f-b94a-2f83cf4a842a"
+Unitful = "1986cc42-f94f-5a68-af5c-568840ba703d"
 
 [extensions]
 AccessorsAxisKeysExt = "AxisKeys"
 AccessorsIntervalSetsExt = "IntervalSets"
 AccessorsStaticArraysExt = "StaticArrays"
 AccessorsStructArraysExt = "StructArrays"
+AccessorsUnitfulExt = "Unitful"
 
 [compat]
 AxisKeys = "0.2"

ext/AccessorsStructArraysExt.jl

@@ -9,6 +9,8 @@ Accessors.set(x::StructArray, o::PropertyLens, v) = set(x, o ∘ StructArrays.co
 Accessors.insert(x::StructArray{<:Union{Tuple, NamedTuple}}, o::PropertyLens, v) = insert(x, o ∘ StructArrays.components, v)
 Accessors.delete(x::StructArray{<:Union{Tuple, NamedTuple}}, o::PropertyLens) = delete(x, o ∘ StructArrays.components)
 
+Accessors.set(x::StructArray{<:Union{Tuple, NamedTuple}}, ::typeof(propertynames), names) = set(x, propertynames ∘ StructArrays.components, names)
+
 # (named)tuple eltypes: only component arrays themselves are needed in the constructor
 # can change component number/names
 Accessors.set(x::StructArray{<:Union{Tuple, NamedTuple}}, ::typeof(StructArrays.components), v) = StructArray(v)

ext/AccessorsUnitfulExt.jl

@@ -0,0 +1,10 @@
+module AccessorsUnitfulExt
+
+import Accessors: set
+using Unitful
+
+# ustrip(unit, _) works automatically because Unitful defines inverse() for it
+# inverse(ustrip) is impossible, so special set() handling is required
+set(obj, ::typeof(ustrip), val) = val * unit(obj)
+
+end

src/functionlenses.jl

@@ -49,6 +49,18 @@ set(obj, ::typeof(Base.splat(=>)), val::Pair) = @set Tuple(obj) = Tuple(val)
 
 set(obj, ::typeof(getproperties), val::NamedTuple) = setproperties(obj, val)
 
+set(x::Union{Tuple,NamedTuple}, ::typeof(propertynames), names) = set(x, propertynames, Tuple(names))
+function set(x::Union{Tuple,NamedTuple}, ::typeof(propertynames), names::Tuple)
+    length(names) == length(x) || throw(ArgumentError("Got $(length(names)) for $(length(x)) properties"))
+    if eltype(names) === Symbol
+        NamedTuple{names}(Tuple(x))
+    elseif eltype(names) <: Integer && names == ntuple(identity, length(names))
+        Tuple(x)
+    else
+        throw(ArgumentError("invalid property names: $names"))
+    end
+end
+
 ################################################################################
 ##### eltype
 ################################################################################

test/test_extensions.jl

@@ -6,6 +6,7 @@ using AxisKeys
 using IntervalSets
 using StaticArrays, StaticNumbers
 using StructArrays
+using Unitful
 
 
 # most of the tests run on Julia 1.9 and later because of package extensions support
@@ -170,6 +171,16 @@ VERSION >= v"1.9-" && @testset "StructArrays" begin
     s = StructArray([S(1, 2), S(3, 4)])
     @test @inferred(set(s, PropertyLens(:a), 10:11))::StructArray == StructArray([S(10, 2), S(11, 4)])
     @test @inferred(set(s, PropertyLens(:a), [:a, :b]))::StructArray == StructArray([S(:a, 2), S(:b, 4)])
+
+    @test_throws "need to overload" set(s, propertynames, (:x, :y))
+    s = StructArray(x=[1, 2], y=[:a, :b])
+    test_getset_laws(propertynames, s, (:u, :v), (1, 2))
+    test_getset_laws(propertynames, s, (1, 2), (:u, :v))
+end
+
+VERSION ≥ v"1.9-" && @testset "Unitful" begin
+    test_getset_laws(ustrip, 1u"m", 2., 3)
+    test_getset_laws(ustrip, 1u"m/mm", 2., 3)
 end
 
 end

test/test_functionlenses.jl

@@ -109,6 +109,20 @@ end
     test_getset_laws(NamedTuple{(:x, :y)}, CartesianIndex(1, 2), (y=3, x=4), (x=5, y=6); cmp=cmp)
 
     test_getset_laws(Accessors.getproperties, 1+2im, (im=4., re=3.), (re=5, im=6); cmp=cmp)
+
+    @testset for obj in [(10, 20.), (x=10, y=20.)]
+        @test (@set propertynames(obj) = 1:2) === (10, 20.)
+        @test (@set propertynames(obj) = (:a, :b)) === (a=10, b=20.)
+        @test_throws Exception (@set propertynames(obj) = 1:3)
+        @test_throws Exception (@set propertynames(obj) = (2, 3))
+        @test_throws Exception (@set propertynames(obj) = (:a, :b, :c))
+        @test_throws Exception (@set propertynames(obj) = (1, :b))
+        @test_throws Exception (@set propertynames(obj) = ("a", "b"))
+    end
+    test_getset_laws(propertynames, (10, 20.), (:a, :b), (1, 2); cmp=(===))
+    test_getset_laws(propertynames, (10, 20.), (1, 2), (:a, :b); cmp=(===))
+    test_getset_laws(propertynames, (a=10, b=20.), (:x, :y), (1, 2); cmp=(===))
+    test_getset_laws(propertynames, (a=10, b=20.), (1, 2), (:x, :y); cmp=(===))
 end
 
 @testset "eltype on Number" begin