Double Dashes "--" inside strings are treated as comments

[steale-dot]

Hey @g2384,
First of all, thanks for the project. I've found a false-positive when working with the formatter on a school project.

The issue is that -- inside string literals is treated as a comment delimiter. So for example, the string "Hi I am Foo <-- Really Foo" gets corrupted to "Hi I am Foo < -- Really Foo". In my concrete use case the testing logic broke as a result.

When I discovered the issue I was using Visual Studio Code with the VHDL-By-HGB Plugin.

I've added a minimal reproducer below:

entity test is
end entity test;

architecture rtl of test is
  constant MSG : string := "This <-- should not happen";
begin
end architecture rtl;

The issue is also reproducible with the web formatter, which I have tested.

---

This is likely related to: https://github.com/g2384/VHDLFormatter/blob/master/VHDLFormatter.ts#L332

EscapeComments uses a plain indexOf("--") with no awareness of string context, and it runs before string literals are masked by escapeText. This means -- inside any quoted string gets incorrectly treated as a comment start.

The fix would be to escape string literals before calling EscapeComments, so that the content inside quotes is already masked by the time comment scanning runs.

I can open up a PR if you like me to.

Regards,
Alessandro