sort for NTuple and other iterables

Project.toml

@@ -1,6 +1,6 @@
 name = "Compat"
 uuid = "34da2185-b29b-5c13-b0c7-acf172513d20"
-version = "4.8.0"
+version = "4.9.0"
 
 [deps]
 Dates = "ade2ca70-3891-5945-98fb-dc099432e06a"

README.md

@@ -70,6 +70,8 @@ changes in `julia`.
 
 ## Supported features
 
+* `sort` for `NTuple` and iterables. ([#46104]) (since Compat 4.9.0)
+
 * `redirect_stdio`, for simple stream redirection. ([#37978]) (since Compat 4.8.0)
 
 * `trunc`, `floor`, `ceil`, and `round` to `Bool`. ([#25085]) (since Compat 4.7.0)
@@ -168,4 +170,5 @@ Note that you should specify the correct minimum version for `Compat` in the
 [#43334]: https://github.com/JuliaLang/julia/issues/43334
 [#43354]: https://github.com/JuliaLang/julia/issues/43354
 [#43852]: https://github.com/JuliaLang/julia/issues/43852
+[#46104]: https://github.com/JuliaLang/julia/issues/46104
 [#48038]: https://github.com/JuliaLang/julia/issues/48038

src/Compat.jl

@@ -706,6 +706,42 @@ if VERSION < v"1.7.0-DEV.1187"
     export redirect_stdio
 end
 
+# https://github.com/JuliaLang/julia/pull/46104
+if VERSION < v"1.10.0-DEV.1404"
+    import Base: sort, Ordering, Forward, ord, lt, tail, copymutable, DEFAULT_STABLE, IteratorSize, HasShape, IsInfinite
+    function sort(v; kws...)
+        size = IteratorSize(v)
+        size == HasShape{0}() && throw(ArgumentError("$v cannot be sorted"))
+        size == IsInfinite() && throw(ArgumentError("infinite iterator $v cannot be sorted"))
+        sort!(copymutable(v); kws...)
+    end
+    sort(::AbstractString; kws...) =
+        throw(ArgumentError("sort(::AbstractString) is not supported"))
+    sort(::Tuple; kws...) =
+        throw(ArgumentError("sort(::Tuple) is only supported for NTuples"))
+
+    function sort(x::NTuple{N}; lt::Function=isless, by::Function=identity,
+                  rev::Union{Bool,Nothing}=nothing, order::Ordering=Forward) where N
+        o = ord(lt,by,rev,order)
+        if N > 9
+            v = sort!(copymutable(x), DEFAULT_STABLE, o)
+            tuple((v[i] for i in 1:N)...)
+        else
+            _sort(x, o)
+        end
+    end
+    _sort(x::Union{NTuple{0}, NTuple{1}}, o::Ordering) = x
+    function _sort(x::NTuple, o::Ordering)
+        a, b = Base.IteratorsMD.split(x, Val(length(x)>>1))
+        merge(_sort(a, o), _sort(b, o), o)
+    end
+    merge(x::NTuple, y::NTuple{0}, o::Ordering) = x
+    merge(x::NTuple{0}, y::NTuple, o::Ordering) = y
+    merge(x::NTuple{0}, y::NTuple{0}, o::Ordering) = x # Method ambiguity
+    merge(x::NTuple, y::NTuple, o::Ordering) =
+        (lt(o, y[1], x[1]) ? (y[1], merge(x, tail(y), o)...) : (x[1], merge(tail(x), y, o)...))
+end
+
 include("deprecated.jl")
 
 end # module Compat

test/runtests.jl

@@ -691,3 +691,36 @@ end
         @test read(path_stdout, String) == content_stdout
     end
 end
+
+# https://github.com/JuliaLang/julia/pull/46104
+@testset "sort(iterable)" begin
+    function tuple_sort_test(x)
+      @test issorted(sort(x))
+      length(x) > 9 && return # length > 9 uses a vector fallback
+      @test 0 == @allocated sort(x)
+    end
+    @testset "sort(::NTuple)" begin
+        @test sort((9,8,3,3,6,2,0,8)) == (0,2,3,3,6,8,8,9)
+        @test sort((9,8,3,3,6,2,0,8), by=x->x÷3) == (2,0,3,3,8,6,8,9)
+        for i in 1:40
+            tuple_sort_test(tuple(rand(i)...))
+        end
+        @test_throws ArgumentError sort((1,2,3.0))
+    end
+    @testset "sort!(iterable)" begin
+        gen = (x % 7 + 0.1x for x in 1:50)
+        @test sort(gen) == sort!(collect(gen))
+        gen = (x % 7 + 0.1y for x in 1:10, y in 1:5)
+        @test sort(gen; dims=1) == sort!(collect(gen); dims=1)
+        @test sort(gen; dims=2) == sort!(collect(gen); dims=2)
+
+        @test_throws ArgumentError("dimension out of range") sort(gen; dims=3)
+
+        @test_throws UndefKeywordError(:dims) sort(gen)
+        @test_throws UndefKeywordError(:dims) sort(collect(gen))
+        @test_throws UndefKeywordError(:dims) sort!(collect(gen))
+
+        @test_throws ArgumentError sort("string")
+        @test_throws ArgumentError("1 cannot be sorted") sort(1)
+    end
+end