Fix spurious warning for import A.: (#267)

Author: c42f

src/parser.jl

@@ -2364,7 +2364,7 @@ function parse_atsym(ps::ParseState, allow_quotes=true)
         # export outer  ==> (export outer)
         # export ($f)   ==> (export ($ f))
         mark = position(ps)
-        if allow_quotes && peek(ps) == K":"
+        if allow_quotes && peek(ps) == K":" && !is_closing_token(ps, peek(ps,2))
             # import A.:+  ==>  (import (importpath A (quote-: +)))
             emit_diagnostic(ps, warning="quoting with `:` is not required here")
         end

test/diagnostics.jl

@@ -40,6 +40,8 @@ end
         Diagnostic(9, 9, :warning, "space between dots in import path")
 	@test diagnostic("import A.:+") ==
         Diagnostic(10, 10, :warning, "quoting with `:` is not required here")
+    # No warning for import `:` symbol
+    @test diagnostic("import A.:, :", allow_multiple=true) == []
     @test diagnostic("import A.(:+)") ==
         Diagnostic(10, 13, :warning, "parentheses are not required here")
     @test diagnostic("export (x)") ==