Compat.IteratorSize and Compat.IteratorEltype (#451)

Author: fredrikekre

README.md

@@ -273,6 +273,9 @@ Currently, the `@compat` macro supports the following syntaxes:
 
 * `unshift!` and `shift!` are now `pushfirst!` and `popfirst!` ([#25100]).
 
+* `Base.IteratorSize` and `Base.IteratorEltype` are available as
+  `Compat.IteratorSize` and `Compat.IteratorEltype` ([#25402]).
+
 * `copy!` and `unsafe_copy!` are now `copyto!` and `unsafe_copyto!` ([#24808]).
 
 * `ipermute!` is now `invpermute!` ([#25168]).
@@ -428,13 +431,16 @@ includes this fix. Find the minimum version from there.
 [#24657]: https://github.com/JuliaLang/julia/issues/24657
 [#24714]: https://github.com/JuliaLang/julia/issues/24714
 [#24785]: https://github.com/JuliaLang/julia/issues/24785
+[#24808]: https://github.com/JuliaLang/julia/issues/24808
 [#25012]: https://github.com/JuliaLang/julia/issues/25012
 [#25021]: https://github.com/JuliaLang/julia/issues/25021
 [#25056]: https://github.com/JuliaLang/julia/issues/25056
 [#25057]: https://github.com/JuliaLang/julia/issues/25057
 [#25100]: https://github.com/JuliaLang/julia/issues/25100
 [#25102]: https://github.com/JuliaLang/julia/issues/25102
+[#25113]: https://github.com/JuliaLang/julia/issues/25113
 [#25162]: https://github.com/JuliaLang/julia/issues/25162
 [#25165]: https://github.com/JuliaLang/julia/issues/25165
 [#25168]: https://github.com/JuliaLang/julia/issues/25168
-[#25113]: https://github.com/JuliaLang/julia/issues/25113
+[#25227]: https://github.com/JuliaLang/julia/issues/25227
+[#25402]: https://github.com/JuliaLang/julia/issues/25402

src/Compat.jl

@@ -1066,6 +1066,15 @@ end
     export pushfirst!, popfirst!
 end
 
+# 0.7.0-DEV.3309
+@static if VERSION < v"0.7.0-DEV.3309"
+    const IteratorSize = Base.iteratorsize
+    const IteratorEltype = Base.iteratoreltype
+else
+    const IteratorSize = Base.IteratorSize
+    const IteratorEltype = Base.IteratorEltype
+end
+
 # 0.7.0-DEV.3173
 @static if !isdefined(Base, :invpermute!)
     const invpermute! = ipermute!

test/runtests.jl

@@ -1069,6 +1069,12 @@ let coolvec = [1,2,3]
     @test popfirst!(coolvec) == 0
 end
 
+# 0.7.0-DEV.3309
+let v = [1, 2, 3]
+    @test Compat.IteratorSize(v) == Base.HasShape()
+    @test Compat.IteratorEltype(v) == Base.HasEltype()
+end
+
 # 0.7.0-DEV.3057
 let A = [0, 0, 0], B = [1, 2, 3]
     @test copyto!(A, B) === A == B