Summary

This draft PR begins migration of HugeGraph from TinkerPop 3.5.x to 3.8.0.

The goal is to align HugeGraph with TinkerPop 3.8 while preserving compatibility with:

• tinkerpop-structure-test
• tinkerpop-process-test

This PR introduces initial compatibility adjustments required for core traversal and predicate handling.

Completed So Far

Dependency & Driver Changes

• Removed gremlin-shaded
• Migrated driver classes (RequestMessage, ResponseMessage, Tokens) to gremlin-util

Core Adjustments

• Updated traversal optimize layer for 3.8 generics changes
• Adapted HugePrimaryKeyStrategy for Mutating API updates
• Migrated ConditionP to align with 3.8 P API
• Partial predicate handling alignment

Build Status

• hugegraph-core builds successfully
• Select predicate-based tests pass
• Full suite currently has categorized failures (see below)

Current Test Status

Full reactor build completes.

Failing areas currently under investigation:

1. Nested predicate handling (NotP, multi-layer AND/OR)
2. Search/index behavior changes
3. Property type behavior
4. Parent/SubEdge condition handling
5. Multi-graph backend initialization edge cases

Next step is to complete recursive predicate tree conversion and map pass/fail status to avoid redundant reruns.

Breaking Changes Observed (3.5 → 3.8)

Preliminary migration notes:

• PBiPredicate.of(...) removed
• P.getOriginalValue() removed
• NotP API changed (uses getPredicates() instead of getPredicate())
• Predicate nesting behavior differs
• Text predicate internals differ

A structured breaking-change list will be maintained as migration progresses.

Next Steps

• Complete recursive predicate tree handling for NotP, AndP, OrP
• Categorize failing tests by root cause
• Ensure full pass on memory backend
• Validate RocksDB/HStore backend compatibility

This PR is intentionally opened as Draft to enable early review and incremental alignment with the roadmap.

Feedback is welcome.