[CALCITE-739] Extend RexUtil.pullFactors to recognize additional common factors (follow-up)

[rubenada]

Jira Link

CALCITE-739

Changes Proposed

The original patch for CALCITE-739 (51e6cb1) implemented some extra factoring, but it also (unnecessarily) may alter the "orientation" of comparison predicates. This can have a certain impact on downstream projects which verify plan forms, e.g. in Hive we detected 150+ tests that fail simply because they expect $a=$b and now they get $b=$a (without any extra pull factors being involved).
This was not the purpose of CALCITE-739.
With some minor adjustments, we should be able to maintain the new feature of extra factoring in RexUtil.pullFactors without changing unnecessarily the authored orientation of certain predicates:

• drop default: return normalizeComparison(rex); in pull() (RexUtil.java:2970): it does no factoring at all, it is pure canonicalization
• in commonFactors, store the original as the value: map.put(normalized, conjunction) rather than map.put(normalized, normalized), so pulled-out factors keep their authored orientation

These changes will reduce the side effects of the original commit (facilitating the eventual upgrade to 1.43 for downstream projects that test plan shapes), keeping the improvement of CALCITE-739 (see specific test RexProgramTest#testSimplifyComparisonSymmetry still passes with the proposed adjustment).

[rubenada]

@xuzifu666 sorry I did not participate of the review of your original PR #5246, could you please take a look at this follow-up proposal?

[xuzifu666]

LGTM, thank you for the improvement! normalizeComparison is indeed unnecessary.

[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

[rubenada]

Thanks for the review @xuzifu666 !