fix: Timestamp.of(java.sql.Timestamp) pre-epoch on exact second

[olavloite]

The fix for negative timestamps in #160 did not take into account the possibility that the pre-epoch timestamp could be on an exact second value. In that case, the additional correction of the calculated second value should not be applied.

Fixesgoogleapis/java-spanner-jdbc#85

[codecov]

Codecov Report

Merging #179 into master will not change coverage.
The diff coverage is 100%.

@@ Coverage Diff @@## master #179 +/- ##
=========================================
Coverage 67.76% 67.76% - Complexity 378 379 +1 
=========================================
Files 36 36 Lines 1967 1967 Branches 259 259 =========================================
Hits 1333 1333 Misses 526 526 Partials 108 108

Impacted Files	Coverage Δ	Complexity Δ
...core/src/main/java/com/google/cloud/Timestamp.java	90.62% <100%> (ø)	26 <0> (+1)	⬆️

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[elharo]

Can you make this method name more conventional? e.g. testOf_exactSecond or some such.

[olavloite]

Done. Although this means that the name of this test is not in line with the other test cases in this file, such as for example ofSqlTimestampPreEpoch.

[elharo]

Section 8.5.2 of the Google style guide addresses this:

When adding new code to a file that is not in Google Style, reformatting the existing code first is recommended, subject to the advice in Section 8.5.1, Reformatting existing code.

If this reformatting is not done, new code is still required to be added in Google Style, even if this creates inconsistencies.

[olavloite]

I've updated all the test cases for Timestamp.of(java.sql.Timestamp) to use consistent naming and assertEquals instead of assertThat....

[elharo]

to be technical, a non-zero remainder. Suggest rephrasing as "the timestamp is less than zero and is not divisible by 1000."

[olavloite]

Changed to fix this by subtracting 1 from the seconds value if the seconds value is less than zero and is not divisible by 1000.

[codyoss]

Good catch