handle single character string views correctly

JuliaLang · May 16, 2020 · b3e1837 · b3e1837
1 parent eba2f11
commit b3e1837
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Showing 2 changed files with 7 additions and 3 deletions.
diff --git a/base/strings/substring.jl b/base/strings/substring.jl
@@ -47,7 +47,7 @@ end
 SubString(s::AbstractString) = SubString(s, 1, lastindex(s))
 SubString{T}(s::T) where {T<:AbstractString} = SubString{T}(s, 1, lastindex(s))
 
-@propagate_inbounds view(s::AbstractString, r) = SubString(s, r)
+@propagate_inbounds view(s::AbstractString, r::UnitRange{<:Integer}) = SubString(s, r)
 @propagate_inbounds maybeview(s::AbstractString, r::UnitRange{<:Integer}) = view(s, r)
 @propagate_inbounds maybeview(s::AbstractString, args...) = getindex(s, args...)
 

diff --git a/test/strings/basic.jl b/test/strings/basic.jl
@@ -175,10 +175,14 @@ end
     @test (@view x[4:end]) isa SubString
 
     # We don't (at present) make non-contiguous SubStrings with views
-    @test_throws MethodError (@view x[[1,3,5]]) == "ace"
+    @test_throws MethodError (@view x[[1,3,5]])
     @test (@views (x[[1,3,5]])) isa String
 
-    @test (@views (x[1], x[1:2], x[[1,4]])) isa Tuple{Char, SubString, String}
+    # We don't (at present) make single character SubStrings with views
+    @test_throws MethodError (@view x[3])
+    @test (@views (x[3])) isa Char
+
+    @test (@views (x[3], x[1:2], x[[1,4]])) isa Tuple{Char, SubString, String}
 end