Bad behaviour with multiple curly braces in format string

[Cogitri]

Hello,

I believe #158 introduced a bug when a to-be-formatted string contains multiple curly braces:

Before 1.83.0, the following snippet:

#include <boost/locale.hpp>
#include <boost/format.hpp>
#include <iostream>

int main() {
	std::cout << boost::locale::format("Test string {{{1}}}") % "num";

	return 0;
}

Returned:

Test String {{num}}

After 1.83.0 it returns:

Test string {{num}

I admit this is sort of an edge case, but I feel like the previous behaviour was more correct.

[Flamefire]

I'm not sure how that specific PR could cause that behavior, but I agree that neither version produces what I'd expect.

Edit: it is rather caused by a refactoring which misses skipping the escaped opening brace

boost::locale::format("Test string {{{1}}}") % "num" should IMO yield Test string {num} as per the documentation:

You can include a literal '{' and '}' by inserting double "{{" or "}}" into the text.

--> There is an escaped brace, a format-placeholder and another escaped brace

[Cogitri]

Thanks for the fix!