Patch up fetching dates from source (backport of #70040) #70117
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This fixes an issue that `fields` has with dates sent in the `###.######` format. If you send a date in the format `#####.######` we'll parse the bit before the decimal place as the number of milliseconds since epoch and we'll parse the bit after the decimal as the number of nanoseconds since the start of that millisecond. This works and is convenient for some folks. Sadly, the code that back the `fields` API for dates doesn't work with the string format in this case - it works with a `double`. `double` is bad for two reasons: 1. It's default string representation is scientific notation and our parsers don't know how to deal with that. 2. It loses precision relative to the string representation. `double` only has 52 bits of mantissa which can precisely store the number of nanoseconds until about 6am on April 15th, 1970. After that it starts to lose precision. This fixed the first issue, getting us the correct string representation is a "quick and dirty" way. It just converts the `double` back to a string. But we still lose precision. Fixing that would require a larger change.....
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…tic#70117) This fixes an issue that `fields` has with dates sent in the `###.######` format. If you send a date in the format `#####.######` we'll parse the bit before the decimal place as the number of milliseconds since epoch and we'll parse the bit after the decimal as the number of nanoseconds since the start of that millisecond. This works and is convenient for some folks. Sadly, the code that back the `fields` API for dates doesn't work with the string format in this case - it works with a `double`. `double` is bad for two reasons: 1. It's default string representation is scientific notation and our parsers don't know how to deal with that. 2. It loses precision relative to the string representation. `double` only has 52 bits of mantissa which can precisely store the number of nanoseconds until about 6am on April 15th, 1970. After that it starts to lose precision. This fixed the first issue, getting us the correct string representation is a "quick and dirty" way. It just converts the `double` back to a string. But we still lose precision. Fixing that would require a larger change.....
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This fixes an issue that
fieldshas with dates sent in the###.######format.If you send a date in the format
#####.######we'll parse the bitbefore the decimal place as the number of milliseconds since epoch and
we'll parse the bit after the decimal as the number of nanoseconds since
the start of that millisecond. This works and is convenient for some
folks. Sadly, the code that back the
fieldsAPI for dates doesn't workwith the string format in this case - it works with a
double.doubleis bad for two reasons:
parsers don't know how to deal with that.
doubleonly has 52 bits of mantissa which can precisely store the number of
nanoseconds until about 6am on April 15th, 1970. After that it starts
to lose precision.
This fixed the first issue, getting us the correct string
representation is a "quick and dirty" way. It just converts the
doubleback to a string. But we still lose precision. Fixing that would require
a larger change.....