Add back * for 1.10 without needing method overwriting

src/strings/basic.jl

@@ -6,27 +6,17 @@ _isannotated(s) = _isannotated(typeof(s))
 # actually from substring.jl
 _isannotated(::SubString{T}) where {T} = _isannotated(T)
 
-# NOTE Too invalidating:
-
-# function (*)(s1::Union{AnnotatedChar, AnnotatedString}, s2::Union{AbstractChar, AbstractString})
-#     annotatedstring(s1, s2)
-# end
-
-# function (*)(s1::Union{AbstractChar, AbstractString}, s2::Union{AnnotatedChar, AnnotatedString})
-#     annotatedstring(s1, s2)
-# end
-
-# function (*)(s1::Union{AnnotatedChar, AnnotatedString}, s2::Union{AnnotatedChar, AnnotatedString})
-#     annotatedstring(s1, s2)
-# end
-
-# function (*)(s1::Union{AbstractChar, AbstractString}, s2::Union{AbstractChar, AbstractString}, ss::Union{AbstractChar, AbstractString}...)
-#     if _isannotated(s1) || _isannotated(s2) || any(_isannotated, ss)
-#         annotatedstring(s1, s2, ss...)
-#     else
-#         string(s1, s2, ss...)
-#     end
-# end
+# The following meta-programming will generate code like:
+#   Base.:*(s_annot::AnnotatedString, s::Union{AbstractChar,AbstractString}...) = annotatedstring(s_annot, s...)
+#   Base.:*(s1::Union{AbstractChar,AbstractString}, s_annot::AnnotatedString, s::Union{AbstractChar,AbstractString}...) = annotatedstring(s1, s_annot, s...)
+# and so on.
+for i in 0:31
+    front = [Symbol('s', j) for j in 1:i]
+    front_typed = [:($s::Union{AbstractChar,AbstractString}) for s in front]
+    @eval function Base.:*($(front_typed...), s_annot::AnnotatedString, s::Union{AbstractChar,AbstractString}...)
+        annotatedstring($(front...), s_annot, s...)
+    end
+end
 
 # # From io.jl
 # join(iterator) = _join_preserve_annotations(iterator)

test/runtests.jl

@@ -670,3 +670,45 @@ end
     @test printstyled(aio, "e", color=:green)   |> isnothing
     @test read(seekstart(aio), AnnotatedString) == styled"{bold:a}{italic:b}{underline:c}{inverse:d}{(fg=green):e}"
 end
+
+@testset "concatenation via *" begin
+    function check_annotated_equal(a::AbstractString, b::AbstractString)
+        if a isa AnnotatedString && b isa AnnotatedString
+            String(a) == String(b) && annotations(a) == annotations(b)
+        else
+            false
+        end
+    end
+
+    s_annot = styled"{red:hello}"
+
+    # Test (styled, styled)
+    @test check_annotated_equal(
+        s_annot * styled"{blue:world}",
+        styled"{red:hello}{blue:world}"
+    )
+
+    # Test (styled, regular)
+    @test check_annotated_equal(
+        s_annot * "world",
+        styled"{red:hello}world"
+    )
+
+    # Test (regular, styled)
+    @test check_annotated_equal(
+        "hello" * s_annot,
+        styled"hello{red:hello}"
+    )
+
+    # Test (styled, regular, styled)
+    @test check_annotated_equal(
+        s_annot * " " * styled"{blue:world}",
+        styled"{red:hello} {blue:world}"
+    )
+
+    # Test (regular, regular, styled)
+    @test check_annotated_equal(
+        "hello" * " " * s_annot,
+        styled"hello {red:hello}"
+    )
+end