support non-tuple propertynames (#79)

Project.toml

@@ -1,7 +1,7 @@
 name = "ConstructionBase"
 uuid = "187b0558-2788-49d3-abe0-74a17ed4e7c9"
 authors = ["Takafumi Arakaki", "Rafael Schouten", "Jan Weidner"]
-version = "1.5.2"
+version = "1.5.3"
 
 [deps]
 LinearAlgebra = "37e2e46d-f89d-539d-b4ee-838fcccc9c8e"

src/ConstructionBase.jl

@@ -82,15 +82,20 @@ else
     end
 end
 
-# names are consecutive integers: return tuple
-# names are symbols: return namedtuple
-# names are empty (object has no properties): also return namedtuple, for backwards compat and generally makes more sense
+# dispatch on eltype(names) to select Tuple vs NamedTuple
+@inline tuple_or_ntuple(names, vals) = tuple_or_ntuple(eltype(names), names, vals)
+# if names are empty (object has no properties): return namedtuple, for backwards compat and generally makes more sense than tuple
 @inline tuple_or_ntuple(names::Tuple{}, vals::Tuple) = NamedTuple{names}(vals)
-@inline tuple_or_ntuple(names::Tuple{Vararg{Symbol}}, vals::Tuple) = NamedTuple{names}(vals)
-@inline function tuple_or_ntuple(names::Tuple{Vararg{Int}}, vals::Tuple)
-    @assert names === ntuple(identity, length(names))
-    vals
+
+# names are consecutive integers: return tuple
+@inline function tuple_or_ntuple(::Type{Int}, names, vals)
+    @assert Tuple(names) == ntuple(identity, length(names))
+    Tuple(vals)
 end
+# names are symbols: return namedtuple
+@inline tuple_or_ntuple(::Type{Symbol}, names, vals) = NamedTuple{Tuple(names)}(vals)
+# otherwise: throw an error
+tuple_or_ntuple(::Type, names, vals) = error("Only Int and Symbol propertynames are supported")
 
 if VERSION >= v"1.7"
     function getproperties(obj)

test/runtests.jl

@@ -319,6 +319,15 @@ if VERSION >= v"1.7"
         @test getproperties(SProp((1, 2))) === ("pi1", "pi2")
         # what should it return?
         @test_broken getproperties(SProp(("a", "b")))
+
+        @test_throws ErrorException getproperties(SProp((1, :a)))
+    end
+
+    @testset "propertynames can be a vector" begin
+        @test getproperties(SProp([:a, :b])) === (a="psa", b="psb")
+        @test getproperties(SProp(Symbol[])) === (;)
+        @test getproperties(SProp([1, 2])) === ("pi1", "pi2")
+        @test getproperties(SProp(Int[])) === ()
     end
 end