[CALCITE-6792] RelJsonReader failed to read RelJsonWriter output if 'NaN' or 'Infinity' approximate numerics are present

[1fanwang]

Jira Link

CALCITE-6792

Changes Proposed

A plan containing NaN or infinity cannot make a RelJson round trip. The writer emits those values as bare tokens, and the reader fails with:

JsonParseException: Non-standard token 'Infinity'

Non-finite approximate literals are now written as JSON strings. When the declared type is approximate, the reader converts those strings back to doubles. Finite numbers remain numeric, and a character literal containing "Infinity" remains a string.

Testing

$ SOURCE=core/src/main/java/org/apache/calcite/rel/externalize/RelJson.java
$ git checkout 5e3326a0a8 -- "$SOURCE"
$ JAVA_HOME=$(/usr/libexec/java_home -v 21) ./gradlew :core:test \
    --tests 'org.apache.calcite.plan.RelWriterTest.testNonFiniteApproxLiteral' \
    --no-daemon --console=plain
Expected: "literal": "Infinity"
     but: "literal": Infinity
1 completed, 1 failed, 0 skipped

$ git checkout 9bace4f2d8 -- "$SOURCE"
$ JAVA_HOME=$(/usr/libexec/java_home -v 21) ./gradlew :core:test \
    --tests 'org.apache.calcite.plan.RelWriterTest.testNonFiniteApproxLiteral' \
    --no-daemon --console=plain
1 completed, 0 failed, 0 skipped
BUILD SUCCESSFUL

[xuzifu666]

please correct your pr title which should be consistent with jira.

[mihaibudiu]

Can you add some round-trip tests, where the plan is serialized and deserialized and compared with the original?

[sonarqubecloud]

Quality Gate passed

Issues
0 New issues
0 Accepted issues

Measures
0 Security Hotspots
100.0% Coverage on New Code
0.0% Duplication on New Code

See analysis details on SonarQube Cloud

[mihaibudiu]

Please squash the commits