Description:
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strtotime() can be given a string which only represents a "date", rather than a specific second-granularity on that date, e.g.

$foo = strtotime('25 May 2017');

Since strtotime() returns a timestamp it must decide on a sensible point on that day to use. As far as I can see, all versions (sensibly) assume 00 for any missing time elements, leading the example above to return a timestamp that represents


"2017-05-25T00:00:00+00:00"

This follows through if some time elements are given, but not others, e.g. 

strtotime('25 May 2017 10pm') => "2017-05-25T22:00:00+00:00"

While it *seems* safe to rely on this behaviour, it would be better to have it as documented behaviour of strtotime().


Expected result:
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Documentation clearly indicates how the sub-day elements of the timestamp are constructed in the absence of time information in the input.