This PR was merged into the 3.x branch.
Discussion
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Fix null coalescing operator with imported macros
Closes#4776
When using the null coalescing operator with a macro imported via the `from` tag, the `TemplateVariable` node inside `MacroReferenceExpression` was deep-cloned, causing the clone to generate a different `$macros` key than the one assigned by `AssignTemplateVariable`. This resulted in a `Call to a member function hasMacro() on null` error.
Commits
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efa004caab Fix null coalescing operator with imported macros
Fabien Potencier
e56cdfdded