Add BitSet (#407)

Author: ararslan

README.md

@@ -211,6 +211,8 @@ Currently, the `@compat` macro supports the following syntaxes:
 
 * `isleaftype` is now `isconcrete` ([#23666])
 
+* `IntSet` is now `BitSet` ([#24282])
+
 ## New macros
 
 * `@__DIR__` has been added ([#18380])
@@ -343,4 +345,5 @@ includes this fix. Find the minimum version from there.
 [#23666]: https://github.com/JuliaLang/julia/issues/23666
 [#23812]: https://github.com/JuliaLang/julia/issues/23812
 [#23931]: https://github.com/JuliaLang/julia/issues/23931
+[#24282]: https://github.com/JuliaLang/julia/issues/24282
 [#22512]: https://github.com/JuliaLang/julia/issues/22532

src/Compat.jl

@@ -709,6 +709,12 @@ if VERSION < v"0.7.0-DEV.912"
     (*)(s1::Union{Char,AbstractString}, ss::Union{Char,AbstractString}...) = string(s1, ss...)
 end
 
+# 0.7.0-DEV.2318
+@static if !isdefined(Base, :BitSet)
+    const BitSet = IntSet
+    export BitSet
+end
+
 include("deprecated.jl")
 
 end # module Compat

test/runtests.jl

@@ -850,6 +850,9 @@ end
 # 0.7
 @test 'a'*"b" == "a"*'b' == 'a'*'b' == "ab"
 
+# 0.7
+@test 1 in BitSet(1:10)
+
 if VERSION < v"0.6.0"
     include("deprecated.jl")
 end