fix: reconstruct current_path when base template defers before blocks

[jasmith-hs]

Description

When a Jinja template extends a base that defers a variable before its block definitions, the eager first-pass output was missing the {% set current_path = '...' %} preamble that all other eager extends scenarios include. Without it, the second pass has no base-template path reference, which would break relative path resolution (e.g., {% include %} calls) inside any such base template.

The pathSetter node — responsible for emitting the current_path reconstruction — was only written when resolveBlockStubs() added deferred tokens (i.e., deferred content inside block bodies). It was not written when the base template itself produced deferred tokens before its blocks (preserveBlocks = true). The fix is a one-character condition change: also set pathSetter when preserveBlocks is true.

This is the root cause of internal HubL issue https://github.com/HubSpotProductSupport/ProductSupport/issues/146621.

BRAVE

Backwards Compatibility

No API or behavioral change for non-deferred templates. The fix only applies when preserveBlocks is already true, which only happens in eager mode when the base template itself defers content.

Rollout and Rollback Plan

• Library change — consumers pick it up on their next version bump
• Rollback: revert the single condition change in JinjavaInterpreter.java

Automated Testing

• itDefersSetInBaseBeforeBlock — verifies first-pass output now includes {% set current_path = '...' %}
• itDefersSetInBaseBeforeBlockSecondPass — verifies the second pass renders correctly once the deferred value is resolved

Verification

• Run EagerExtendsTagTest locally; both new tests pass

Expect Dependencies to Fail

None expected.

---

PR description authored by Claude Code

REVIEWERS: Please review both the code changes and the answers above, and validate that they match the expectations for BRAVE