adding backward compatibility for string-to-double conversion

[bailaC]

Adding backward compatibility for string to double conversion as mentioned in
#1257 (comment)

[codecov]

Codecov Report

Attention: 2 lines in your changes are missing coverage. Please review.

Comparison is base (acbeeea) 47.82% compared to head (f319415) 47.85%.
Report is 1 commits behind head on master.

Additional details and impacted files

@@            Coverage Diff             @@
##           master    #1284      +/-   ##
==========================================
+ Coverage   47.82%   47.85%   +0.03%     
==========================================
  Files          41       41              
  Lines        3473     3477       +4     
  Branches     1888     1889       +1     
==========================================
+ Hits         1661     1664       +3     
  Misses        446      446              
- Partials     1366     1367       +1     

Flag	Coverage Δ
unittests	47.85% <71.42%> (+0.03%)	⬆️

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Files	Coverage Δ
hardware_interface/src/lexical_casts.cpp	50.00% <71.42%> (+10.00%)	⬆️

[aprotyas]

Left a couple of comments.

---

Also, I think it would be cleaner to leave stod() alone and have two versions of impl::stod() instead. That way we don't end up changing the API contract when touching individual implementations… what do you think of this?

namespace hardware_interface
{

namespace impl
{
std::optional<double> stod(const std::string & s)
{
#if __cplusplus < 201703L
    // Impl with std::istringstream
    ...
    if (stream.fail() || !stream.eof())
    {
        return std::nullopt;
    }
    return result;
#else
    // Impl with std::from_chars
    ...
    if (parse_result.ec == std::errc())
    {
        return result_value;
    }
    return std::nullopt;
#endif
}
}  // namespace impl

double stod(const std::string & s)
{
    if (const auto result = impl::stod(s))
    {
        return *result;
    }
    throw std::invalid_argument("Failed converting string to real number");
}
}

[aprotyas]

LGTM with a couple of comments

[destogl]

This looks good to me and it seems that the tests are happy too :)

[christophfroehlich]

nice, works for me (on debian11 and ubuntu 22.04)

[saikishor]

LGTM

[destogl]

@Mergifyio backport iron humble

[mergify]

backport iron humble

✅ Backports have been created

• #1289 adding backward compatibility for string-to-double conversion (backport #1284) has been created for branch iron
• #1290 adding backward compatibility for string-to-double conversion (backport #1284) has been created for branch humble