This patch addresses a static analysis issue reported by Cppcheck 2.9
where an assertion in the toml/region.hpp header would compare two
container's (that are known to be of type std::vector<char>) begin() and
end() iterators in order to verify that they are the same. This
assertion either passes or invokes undefined behavior. Which isn't
technically wrong because calling code must always ensure that
preconditions are met and assertions therefore pass anyway but it does
make the value that is added by having the assertion in the first place
marginal. Fortunately, the assertion was easy to rewrite: Just compare
the container's address itself. This is well-defined regardless of
whether the assertion will pass or fail.
This patch addresses a static analysis issue reported by Cppcheck 2.9
where several classes in the toml/datetime.hpp header explicitly default
all their special member functions, including the default constructor,
but don't provide initializers for their data members. This might or
might not have caused any observable surprising behavior but I agree
with Cppcheck on this one in that an explicitly defaulted default
constructor should be expected to initialize all data members. So let's
do that.
The fstream classes are notorious for their non-existent error handling.
This adds a C-style fILE * IO (fopen(), etc.) alternative interface, so
that if a user needs reliable error handling, they can use that, albeit
more inconvenient, but more robust approach.
Instead of static_cast calls that convert int to char, literals of type
char are now used directly with the value encoded via escape sequence.
The benefits are:
- code without static_cast is much more compact and expresses intent
better
- fixed value truncation warning on some compilers (e.g. C4309 on Visual
Studio 2017)
Taking this parameter by const reference forces us to copy it (because
we know we're going to store it). Taking it by r-value reference would
suggest that we _might_ take ownership over it and would also force the
user to make a copy if they wish to retain the original value.
Taking this parameter by value however clearly gives us ownership of its
content without forcing a copy if it's implicit conversion from
`const char*` or explicitly handed over to us by the user via std::move.
current code mistakenly allows the following TOML file.
```toml
a.b = 42 # table "a" is defined here, implicitly
a = {c = 3.14} # table "a" is overwritten here
```
But we need to allow the following (structually similar) TOML file.
```toml
a.b = 42 # table "a" is defined here, implicitly
a.c = 3.14 # table "a" is merged with {c = 3.14}
```
To distinguish those, we check whether the current table is defined as
an inline table or via dotted key. If the table we are inserting is
defined via dotted key, we accept it and merge the table. If the table
being inserted is defined as an inline table, then we report an error.
As described in issue #173, this warning is raised on various platforms
and in various build types. For example, g++ 11 in release mode will
cause this warning to be raised. This change fixes this warning.
