fix(query): return full float value in query results

[qujoux]

Description

Updates float formatting to express full values. Switches from %f to %g, which according to Golang docs will use as many digits as necessary to express the value.

for %g [the default precision] is the smallest number of digits necessary to identify the value uniquely.

I had trouble getting t to run. A new unit test passes with:

go test github.com/hypermodeinc/dgraph/v25/query

Closes #9491.

Discussion

This changes the output format but not semantics of float values in result data. Currently floats have a fixed precision of 6, filled with trailing zeros as necessary.

{ "float": 1.000000 }

The new specifier %g drops unnecessary trailing zeros.

{ "float": 1 }

I think this OK as they are semantically equivalent. Since unnecessary characters are dropped, it also saves bytes on the wire. It also aligns with the bigfloat format, which never gives trailing zeros.

Checklist

• Code compiles correctly and linting passes locally
• For all code changes, an entry added to the CHANGELOG.md file describing and linking to this PR
• Tests added for new functionality, or regression tests for bug fixes added as applicable

[qujoux]

Thank you for reviewing. Just a note that I've got t running and I'm working on getting these tests cleaned up.

[matthewmcneely]

Thank you for reviewing. Just a note that I've got t running and I'm working on getting these tests cleaned up.

@qujoux Be aware I'm in the middle of improving the t harness, not sure what you're planning when you say "cleaned up", but wanted to avoid duplicate efforts: #9485

[qujoux]

Thank you! I'm just aiming to get tests passing for this PR, I see there are JSON comparisons scattered around that expect the old float format. Faster testing will be a nice improvement.

[qujoux]

Some tests are giving Docker errors I don't understand, but they seem to have no float comparisons in them. I think all the relevant tests are passing now.

[qujoux]

Sorry about the bumpy road, and thank you for reviewing!