print @var_str in NamedTuple by show_sym (#42729)

fix #42719

Author: inkydragon

base/namedtuple.jl

@@ -165,7 +165,8 @@ function show(io::IO, t::NamedTuple)
         typeinfo = get(io, :typeinfo, Any)
         print(io, "(")
         for i = 1:n
-            print(io, fieldname(typeof(t),i), " = ")
+            show_sym(io, fieldname(typeof(t), i))
+            print(io, " = ")
             show(IOContext(io, :typeinfo =>
                            t isa typeinfo <: NamedTuple ? fieldtype(typeinfo, i) : Any),
                  getfield(t, i))

test/show.jl

@@ -1843,6 +1843,12 @@ end
     # issue #34343
     @test showstr([[1], Int[]]) == "[[1], $Int[]]"
     @test showstr([Dict(1=>1), Dict{Int,Int}()]) == "[Dict(1 => 1), Dict{$Int, $Int}()]"
+
+    # issue #42719, NamedTuple with @var_str
+    @test replstr((; var"a b"=1)) == """(var"a b" = 1,)"""
+    @test replstr((; var"#var#"=1)) == """(var"#var#" = 1,)"""
+    @test replstr((; var"a"=1, b=2)) == "(a = 1, b = 2)"
+    @test replstr((; a=1, b=2)) == "(a = 1, b = 2)"
 end
 
 @testset "#14684: `display` should print associative types in full" begin