[CALCITE-5613] Add assert for number of args for metadata methods at CacheGeneratorUtil

• Type: Improvement
• Status: Closed
• Priority: Trivial
• Resolution: Fixed
• Affects Version/s: 1.34.0
• Fix Version/s: 1.38.0
• Component/s: core
• Labels: pull-request-available
• Assignee: Unassigned
• Reporter: Sergey Nuyanzin
• Created: 27/Mar/23 23:33
• Updated: 17/Oct/24 22:41
• Resolved: 17/Oct/24 22:41

Description

The problem is that it implicitly implies that method should have 2+ args based on org.apache.calcite.rel.metadata.janino.CacheGeneratorUtil.CacheKeyStrategy#safeArgList.

At the same time different libs like JaCoCo could generate extra methods like private static boolean[] org.apache.calcite.rel.metadata.BuiltInMetadata$Predicates$Handler.$jacocoInit().

It took several hours to realize it.... since currently it complains like

java.lang.IllegalArgumentException: fromIndex(2) > toIndex(0)
	at java.base/java.util.AbstractList.subListRangeCheck(AbstractList.java:509)
	at java.base/java.util.AbstractList.subList(AbstractList.java:497)
	at org.apache.calcite.rel.metadata.janino.CacheGeneratorUtil$CacheKeyStrategy$1.safeArgList(CacheGeneratorUtil.java:213)
	at org.apache.calcite.rel.metadata.janino.CacheGeneratorUtil$CacheKeyStrategy$1.cacheKeyBlock(CacheGeneratorUtil.java:205)
...

The idea is to put assert something like that

assert method.getParameterCount() >= 2 : method.toString();

to simplify the process of finding the root cause

Issue Links

• links to: GitHub Pull Request #3941