Add NonBlockingByteBufferParser tests for JSON-escaped surrogate pairs in field names (#1581)

[Copilot]

NonBlockingByteBufferParser was reported to throw Invalid UTF-8: Illegal surrogate character when parsing field names containing JSON-escaped surrogate pairs (e.g. {"\\uD834\\uDd1e": 1}), while the same input worked correctly in string values and in the NonBlockingByteArrayParser.

The fix from #1541 was correctly applied to NonBlockingUtf8JsonParserBase._parseEscapedName, which is shared by both NonBlockingByteArrayParser and NonBlockingByteBufferParser via inheritance. The gap was test coverage: AsyncEscapedSurrogateInFieldName1541Test only exercised the ByteArray parser via asyncForBytes(), never the ByteBuffer parser via asyncForByteBuffer().

Changes

• New test class AsyncByteBufferEscapedSurrogateInFieldName1581Test mirrors the ByteArray coverage in AsyncEscapedSurrogateInFieldName1541Test for the NonBlockingByteBufferParser, covering:
  • Chunk sizes of 1, 2, 3, 7, and 100 bytes — exercising both the split-escape slow path (_finishPropertyWithEscape) and the inline fast path
  • Regular double-quoted and apostrophe-quoted field names
  • Name variations across quad-boundary alignments, multiple consecutive surrogate pairs, and long names (>12 bytes)
  • Error cases: lone high surrogate and lone low surrogate

Warning

Firewall rules blocked me from connecting to one or more addresses (expand for details)

I tried to connect to the following addresses, but was blocked by firewall rules:

• central.sonatype.com
  • Triggering command: /usr/lib/jvm/temurin-17-jdk-amd64/bin/java /usr/lib/jvm/temurin-17-jdk-amd64/bin/java --enable-native-access=ALL-UNNAMED -classpath /usr/share/apache-maven-3.9.13/boot/plexus-classworlds-2.9.0.jar -Dclassworlds.conf=/usr/share/apache-maven-3.9.13/bin/m2.conf -Dmaven.home=/usr/share/apache-maven-3.9.13 -Dlibrary.jansi.path=/usr/share/apache-maven-3.9.13/lib/jansi-native -Dmaven.multiModuleProjectDirectory=/home/REDACTED/work/jackson-core/jackson-core org.codehaus.plexus.classworlds.launcher.Launcher test -pl . -Dtest=AsyncEscapedSurrogateInFieldName1541Test -q (dns block)
  • Triggering command: /usr/lib/jvm/temurin-17-jdk-amd64/bin/java /usr/lib/jvm/temurin-17-jdk-amd64/bin/java --enable-native-access=ALL-UNNAMED -classpath /home/REDACTED/.m2/wrapper/dists/apache-maven-3.9.11/a2d47e15/boot/plexus-classworlds-2.9.0.jar -Dclassworlds.conf=/home/REDACTED/.m2/wrapper/dists/apache-maven-3.9.11/a2d47e15/bin/m2.conf -Dmaven.home=/home/REDACTED/.m2/wrapper/dists/apache-maven-3.9.11/a2d47e15 -Dlibrary.jansi.path=/home/REDACTED/.m2/wrapper/dists/apache-maven-3.9.11/a2d47e15/lib/jansi-native -Dmaven.multiModuleProjectDirectory=/home/REDACTED/work/jackson-core/jackson-core org.codehaus.plexus.classworlds.launcher.Launcher test -Dtest=AsyncEscapedSurrogateInFieldName1541Test -q (dns block)
  • Triggering command: /usr/lib/jvm/temurin-17-jdk-amd64/bin/java /usr/lib/jvm/temurin-17-jdk-amd64/bin/java --enable-native-access=ALL-UNNAMED -classpath /usr/share/apache-maven-3.9.13/boot/plexus-classworlds-2.9.0.jar -Dclassworlds.conf=/usr/share/apache-maven-3.9.13/bin/m2.conf -Dmaven.home=/usr/share/apache-maven-3.9.13 -Dlibrary.jansi.path=/usr/share/apache-maven-3.9.13/lib/jansi-native -Dmaven.multiModuleProjectDirectory=/home/REDACTED/work/jackson-core/jackson-core org.codehaus.plexus.classworlds.launcher.Launcher test -Dtest=AsyncEscapedSurrogateInFieldName1541Test -Dmaven.parent.skip=true -q (dns block)

If you need me to access, download, or install something from one of these locations, you can either:

• Configure Actions setup steps to set up my environment, which run before the firewall is enabled
• Add the appropriate URLs or hosts to the custom allowlist in this repository's Copilot coding agent settings (admins only)

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[pjfanning]

I'll look into retargeting this at 2.21 branch to add regression testing and to see if there is an issue that exists only in the 2.x branches.

[cowtowncoder]

@pjfanning Yes: #1567 only covers blocking parser, limited and not covering async variant(s).

[github-actions]

📈 Overall Code Coverage

Metric	Coverage	Change
Instructions	83.07%	📈 +0.020%
Branches	75.74%	📈 +0.030%

Overall project coverage from JaCoCo test results. Change values compare against the latest base branch build.

[cowtowncoder]

@pjfanning I could also just merge this in 3.x for improved code coverage? Let me know if that makes sense -- leaving as-is for now.

[pjfanning]

@cowtowncoder merge it in 3.x or 3.1 for the extra coverage.

#1583 is the 2.21 equivalent but it fails. I got Copilot to draft a proposal for a fix.