July 19, 2020
https://issues.dlang.org/show_bug.cgi?id=21057

          Issue ID: 21057
           Summary: getopt, function setter for a long option receive the
                    key, not the value
           Product: D
           Version: D2
          Hardware: All
                OS: All
            Status: NEW
          Severity: major
          Priority: P1
         Component: phobos
          Assignee: nobody@puremagic.com
          Reporter: b2.temp@gmx.com

Not sure if it is a major one, considering that nobody has reported it yet but this the setter for a long option is called with the wrong part of the option, e.g for "--key=value" the setter is called with "key":

---
void setValue(string value)
{
    assert(value == value.stringof, value);
}

void main(string[] args)
{
    args ~= "--key=value";
    import std.getopt;
    getopt(args, "key", &setValue);
}
---

unless i handle the fix by myself, open a PR in for the stable branch please.

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