Add public to the @compat macro

Project.toml

@@ -1,6 +1,6 @@
 name = "Compat"
 uuid = "34da2185-b29b-5c13-b0c7-acf172513d20"
-version = "4.9.0"
+version = "4.10.0"
 
 [deps]
 Dates = "ade2ca70-3891-5945-98fb-dc099432e06a"

README.md

@@ -70,6 +70,8 @@ changes in `julia`.
 
 ## Supported features
 
+* `@public` as an alias for the `public` keyword (no-op on Julia 1.10 and earlier). ([#50105]) (since Compat 4.10.0)
+
 * `sort` for `NTuple` and other iterables. ([#46104]) (since Compat 4.9.0)
 
 * `redirect_stdio`, for simple stream redirection. ([#37978]) (since Compat 4.8.0)
@@ -172,3 +174,4 @@ Note that you should specify the correct minimum version for `Compat` in the
 [#43852]: https://github.com/JuliaLang/julia/issues/43852
 [#46104]: https://github.com/JuliaLang/julia/issues/46104
 [#48038]: https://github.com/JuliaLang/julia/issues/48038
+[#50105]: https://github.com/JuliaLang/julia/issues/50105

src/Compat.jl

@@ -389,7 +389,7 @@ end
 if VERSION < v"1.9.0-DEV.1163"
     import Base: IteratorSize, HasLength, HasShape, OneTo
     export stack
-    
+
     """
         stack(iter; [dims])
 
@@ -741,6 +741,31 @@ if VERSION < v"1.10.0-DEV.1404"
         (lt(o, y[1], x[1]) ? (y[1], merge(x, tail(y), o)...) : (x[1], merge(tail(x), y, o)...))
 end
 
+# https://github.com/JuliaLang/julia/pull/50105
+export @public
+"""
+    @public foo, bar, baz
+
+Equivalent to `public foo, bar, baz` on versions of Julia that support the `public` keyword;
+a no-op on versions of Julia that do not support the `public` keyword.
+"""
+macro public(arg)
+    symbols = _get_symbols(arg)
+    if VERSION >= v"1.11.0-DEV.469"
+        esc(Expr(:public, symbols...))
+    end
+end
+
+_get_symbols(symbol::Symbol) = (symbol,)
+function _get_symbols(symbols)
+    if Base.isexpr(symbols, :tuple) && all(x -> x isa Symbol, symbols.args)
+        symbols.args
+    else
+        throw(ArgumentError("cannot mark `$symbols` as public. Try `@public foo, bar, baz`."))
+    end
+end
+
+
 include("deprecated.jl")
 
 end # module Compat

test/runtests.jl

@@ -238,7 +238,7 @@ end
 
 # https://github.com/JuliaLang/julia/pull/43852
 @testset "@assume_effects" begin
-    # ensure proper macro hygiene across versions 
+    # ensure proper macro hygiene across versions
     Compat.@assume_effects :total foo() = true
     Compat.@assume_effects bar() = true
     @test foo()
@@ -724,3 +724,21 @@ end
         @test_throws ArgumentError("1 cannot be sorted") sort(1)
     end
 end
+
+module Mod50105
+    using Compat
+    @public foo, bar, baz
+end
+
+# https://github.com/JuliaLang/julia/pull/50105
+@testset "@public" begin
+    @public foo_50105
+    # foo_50105 = 4 # Uncommenting this line would cause errors due to https://github.com/JuliaLang/julia/issues/51325
+    @test Base.isexported(@__MODULE__, :foo_50105) === false
+    VERSION >= v"1.11.0-DEV.469" && @test Base.ispublic(@__MODULE__, :foo_50105)
+    @test Base.isexported(Mod50105, :bar) === false
+    VERSION >= v"1.11.0-DEV.469" && @test Base.ispublic(Mod50105, :bar)
+
+    @test_throws LoadError @eval @public 4, bar
+    @test_throws LoadError @eval @public foo bar
+end