[magnusp]

Fixes #198

Pure move, zero behavior change. Extracts the SQLite REAL text formatter from LibsqlResultSet into a package-private SqliteRealText with a package-private static String format(double).

Base note: this PR targets test/i195-pin-jdbc-behaviors, the parent stack link (wave 0 characterization tests, 9 new tests). It is not based on main.

Diff stat

 .../magnusp/libsql/jdbc/LibsqlResultSet.java       | 264 +-------------------
 .../github/magnusp/libsql/jdbc/SqliteRealText.java | 272 +++++++++++++++++++++
 2 files changed, 274 insertions(+), 262 deletions(-)

Proof the moved lines are unchanged

Old LibsqlResultSet.java lines 187–444 (258 lines) vs SqliteRealText.java lines 14–271 — the only differing line is the entry-method signature, which the issue requires renaming and widening to package-private:

$ git show origin/test/i195-pin-jdbc-behaviors:.../LibsqlResultSet.java | sed -n '187,444p' > /tmp/blk-old.txt
$ sed -n '14,271p' .../SqliteRealText.java > /tmp/blk-new.txt
$ diff /tmp/blk-old.txt /tmp/blk-new.txt
32c32
<     private static String sqliteRealText(double value) {
---
>     static String format(double value) {

Everything else — the two explanatory comments, the four power tables (FP_POWERS_OF_TEN, FP_POWER_SCALES, FP_POWER_SCALE_LOW, plus FP_POWER_SCALE_HIGH), roundTripsTo, fpPowerOfTenToTwo, fpPowerOfTwoToTen, fpPowerOfTen, fpNormalizeHigh, fpMultiplyWide, fpMultiplyHigh, and fpUnsigned — is identical text, at identical indentation, with method names, constants, comments, and arithmetic byte for byte. No BigDecimal.toPlainString, Double.toString, String.format, or %g.

The only other edit in LibsqlResultSet is removing the now-unused java.math.BigInteger import (its only use lived in the moved code; BigDecimal is still used).

Call sites repointed:

• getString (was 181, now 180): case Value.Float f -> SqliteRealText.format(f.value());
• getBytes (was 641, now 381): case Value.Float f -> SqliteRealText.format(f.value()).getBytes(...);

Behavior preserved: negative zero renders 0.0, exponents render signed and zero padded to two digits, NaN renders NaN, and fixed notation applies when the decimal exponent is between -4 and 16.

Line counts

File	Before	After
LibsqlResultSet.java	1498	1238 (under the 1250 gate)
SqliteRealText.java	—	272

Lanes

$ ./mvnw -pl libsql-jdbc -am test
[INFO] Tests run: 383, Failures: 0, Errors: 0, Skipped: 0
[INFO] BUILD SUCCESS

$ ./mvnw spotless:apply
[INFO] BUILD SUCCESS
$ ./mvnw spotless:check
[INFO] BUILD SUCCESS

$ ./mvnw -pl libsql-conformance -am verify
[INFO] Tests run: 272, Failures: 0, Errors: 0, Skipped: 7
[INFO] BUILD SUCCESS

No test file, dependency, or pom.xml change. No public surface change. Nothing else in LibsqlResultSet moved or renamed.

[magnusp]

Root verdict: PASS at 9ee30e6.

Verifier proved the 258-line block moved byte-identically, with only sqliteRealText renamed to format. Both types stay package-private. 383 unit tests, 272 conformance tests, spotless green, and a negative-zero probe that bit and was reverted. Diff is 2 files, +274/-262.

The Xerial Control lane failed in PreparedStatementThreadTest.testPreparedStmtConcurrentCloseSegFault, which runs the vendored xerial driver and never loads this module. It is a known race in the reference driver and unrelated to the patch. Re-running that job. Countersign: root, 9ee30e6.