Add Compat.Unicode for standard library Unicode (#432)

* Add Compat.Unicode for standard library Unicode

* Define titlecase only on Julia 0.5

* Remove normalize and isassigned from exports

* Add textwidth deprecation

README.md

@@ -79,6 +79,12 @@ Currently, the `@compat` macro supports the following syntaxes:
   `CartesianRange` now has two type parameters, so using them as
   fields in other `struct`s requires manual intervention.
 
+## Module Aliases
+
+* In 0.6, some 0.5 iterator functions have been moved to the `Base.Iterators`
+  module. Code can be written to work on both 0.5 and 0.6 by `import`ing or
+  `using` the `Compat.Iterators` module instead. ([#18839])
+
 * `using Compat.Test`, `using Compat.SharedArrays`, `using Compat.Mmap`, and `using
   Compat.DelimitedFiles` are provided on versions older than 0.7, where these are not yet
   part of the standard library. ([#23931])
@@ -89,11 +95,8 @@ Currently, the `@compat` macro supports the following syntaxes:
 * `using Compat.Dates` is provided on versions older than 0.7, where this library is not
   yet a part of the standard library. ([#24459])
 
-## Module Aliases
-
-* In 0.6, some 0.5 iterator functions have been moved to the `Base.Iterators`
-  module. Code can be written to work on both 0.5 and 0.6 by `import`ing or
-  `using` the `Compat.Iterators` module instead. ([#18839])
+* `using Compat.Unicode` is provided on versions older than 0.7, where this library is not
+  yet a part of the standard library. ([#25021])
 
 ## New functions, macros, and methods
 
@@ -238,8 +241,6 @@ Currently, the `@compat` macro supports the following syntaxes:
 
 * `IntSet` is now `BitSet` ([#24282])
 
-* `strwidth` and `charwidth` are now merged into `textwidth` ([#23667]).
-
 * `Complex32`, `Complex64`, and `Complex128` are now `ComplexF16`, `ComplexF32`, and
   `ComplexF64`, respectively ([#24647]).
 
@@ -378,7 +379,6 @@ includes this fix. Find the minimum version from there.
 [#23427]: https://github.com/JuliaLang/julia/issues/23427
 [#23570]: https://github.com/JuliaLang/julia/issues/23570
 [#23666]: https://github.com/JuliaLang/julia/issues/23666
-[#23667]: https://github.com/JuliaLang/julia/issues/23667
 [#23757]: https://github.com/JuliaLang/julia/issues/23757
 [#23812]: https://github.com/JuliaLang/julia/issues/23812
 [#23931]: https://github.com/JuliaLang/julia/issues/23931
@@ -392,3 +392,4 @@ includes this fix. Find the minimum version from there.
 [#24652]: https://github.com/JuliaLang/julia/issues/24652
 [#24657]: https://github.com/JuliaLang/julia/issues/24657
 [#24785]: https://github.com/JuliaLang/julia/issues/24785
+[#25021]: https://github.com/JuliaLang/julia/issues/25021

src/Compat.jl

@@ -797,13 +797,6 @@ end
     export BitSet
 end
 
-# 0.7.0-DEV.1930
-@static if !isdefined(Base, :textwidth)
-    textwidth(c::Char) = charwidth(c)
-    textwidth(c::AbstractString) = strwidth(c)
-    export textwidth
-end
-
 # 0.7.0-DEV.2116
 @static if VERSION < v"0.7.0-DEV.2116"
     import Base: spdiagm
@@ -919,6 +912,47 @@ end
     export ComplexF64
 end
 
+# 0.7.0-DEV.2915
+module Unicode
+    export graphemes, textwidth, isvalid,
+           islower, isupper, isalpha, isdigit, isxdigit, isnumeric, isalnum,
+           iscntrl, ispunct, isspace, isprint, isgraph,
+           lowercase, uppercase, titlecase, lcfirst, ucfirst
+
+    if VERSION < v"0.7.0-DEV.2915"
+        # 0.7.0-DEV.1930
+        if !isdefined(Base, :textwidth)
+            textwidth(c::Char) = charwidth(c)
+            textwidth(c::AbstractString) = strwidth(c)
+        end
+
+        isnumeric(c::Char) = isnumber(c)
+
+        # 0.6.0-dev.1404 (https://github.com/JuliaLang/julia/pull/19469)
+        if !isdefined(Base, :titlecase)
+            titlecase(c::Char) = isascii(c) ? ('a' <= c <= 'z' ? c - 0x20 : c) :
+                Char(ccall(:utf8proc_totitle, UInt32, (UInt32,), c))
+
+            function titlecase(s::AbstractString)
+                startword = true
+                b = IOBuffer()
+                for c in s
+                    if isspace(c)
+                        print(b, c)
+                        startword = true
+                    else
+                        print(b, startword ? titlecase(c) : c)
+                        startword = false
+                    end
+                end
+                return String(take!(b))
+            end
+        end
+    else
+        using Unicode
+    end
+end
+
 include("deprecated.jl")
 
 end # module Compat

src/deprecated.jl

@@ -188,3 +188,7 @@ else
     import Base.@irrational
     import Base.LinAlg.BLAS.@blasfunc
 end
+
+if VERSION < v"0.7.0-DEV.2915"
+    Base.@deprecate textwidth Compat.Unicode.textwidth
+end

test/runtests.jl

@@ -320,10 +320,10 @@ let s = "Koala test: 🐨"
 end
 
 # julia#17155, tests from Base Julia
-@test (uppercase∘hex)(239487) == "3A77F"
+@test (Compat.Unicode.uppercase∘hex)(239487) == "3A77F"
 let str = randstring(20)
-    @test filter(!isupper, str) == replace(str, r"[A-Z]", "")
-    @test filter(!islower, str) == replace(str, r"[a-z]", "")
+    @test filter(!Compat.Unicode.isupper, str) == replace(str, r"[A-Z]", "")
+    @test filter(!Compat.Unicode.islower, str) == replace(str, r"[a-z]", "")
 end
 
 # julia#19950, tests from Base (#20028)
@@ -919,8 +919,8 @@ end
 @test 1 in BitSet(1:10)
 
 # 0.7.0-DEV.1930
-@test textwidth("A") == 1
-@test textwidth('A') == 1
+@test Compat.Unicode.textwidth("A") == 1
+@test Compat.Unicode.textwidth('A') == 1
 
 # 0.7
 @test diagm(0 => ones(2), -1 => ones(2)) == [1.0 0.0 0.0; 1.0 1.0 0.0; 0.0 1.0 0.0]
@@ -985,6 +985,18 @@ end
 @test ComplexF32 === Complex{Float32}
 @test ComplexF64 === Complex{Float64}
 
+# 0.7.0-DEV.2915
+module Test25021
+    using Compat
+    using Compat.Test
+    using Compat.Unicode
+    @test isdefined(@__MODULE__, :Unicode)
+
+    @test !isnumeric('a')
+    @test isnumeric('1')
+    @test titlecase("firstname lastname") == "Firstname Lastname"
+end
+
 if VERSION < v"0.6.0"
     include("deprecated.jl")
 end