leave out the tightening from this PR, with TODO note

JuliaLang · Dec 24, 2024 · 766286e · 766286e
1 parent d620954
commit 766286e
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Showing 2 changed files with 5 additions and 12 deletions.
diff --git a/base/generator_eltype.jl b/base/generator_eltype.jl
@@ -3,15 +3,12 @@ function eltype(::Type{Generator{A, typeof(identity)}}) where {A}
 end
 
 function eltype(::Type{Generator{A, Fix1{typeof(getindex), B}}}) where {A, B}
-    function h(::Type{Type{T}}) where {T}
-        T
-    end
-    function h(::Type{<:Type})
-        Any
-    end
     if B <: Type
-        # a user may overload `getindex(user_type)` to return a non-`Vector` `AbstractVector`
-        AbstractVector{h(B)}
+        # TODO: theoretically we could be more precise here and return a subtype
+        # of `AbstractVector`. The problem is that several packages do dubious
+        # punning of `getindex`. See
+        # https://github.com/mcabbott/AxisKeys.jl/issues/163
+        Any
     elseif (eltype(A) == keytype(B)) || ((eltype(A) <: Integer) && (keytype(B) <: Integer))
         valtype(B)
     else

diff --git a/test/iterators.jl b/test/iterators.jl
@@ -1016,10 +1016,6 @@ end
 end
 
 @testset "`eltype` for `Generator` involving `Fix` and `getindex`/`getfield` (issue #41519)" begin
-    @testset "special cases" begin
-        (f, i) = (Base.Fix1(getindex, Int), [3, 7])
-        @test AbstractVector{Int} >: @inferred eltype(Iterators.map(f, i))
-    end
     @testset "correct `eltype`" begin
         for (f, i) ∈ (
             (Base.Fix1(getindex, Int), [3, 7]),