Fix merge tree conflicts between Scope and non-Scope nodes #550
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When merging trees, conflicts between a non-Scope node (e.g., `G = C`) and a Scope (e.g., `class G < B; end`) were not being detected. The Scope was simply added to the tree without creating a conflict marker. This commit fixes two issues: 1. `TreeMerger#visit` now handles the case where a Scope conflicts with a non-Scope previous definition. When this occurs, it creates a conflict tree and returns early (since the entire scope is in conflict, not just the header). 2. `ConflictTreeMerger#visit_all` now resets `last_conflict_tree` when encountering a non-`ConflictTree` node. Previously, this variable was never reset, causing non-adjacent ConflictTrees to be incorrectly merged together. For testing, this commit extends `test_merge_create_conflict_tree_constants_and_scopes` to include a constant `G = C` in LHS and `class G < B; end` in RHS. The expected output now includes a conflict block for G showing both the constant assignment and class definition
egiurleo
approved these changes
Jan 6, 2026
amomchilov
approved these changes
Jan 6, 2026
Morriar
approved these changes
Jan 6, 2026
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When merging trees, conflicts between a non-Scope node (e.g.,
G = C) and a Scope (e.g.,class G < B; end) were not being detected. The Scope was simply added to the tree without creating a conflict marker.This commit fixes two issues:
TreeMerger#visitnow handles the case where a Scope conflicts with a non-Scope previous definition. When this occurs, it creates a conflict tree and returns early (since the entire scope is in conflict, so there is no need to visit the children of the scope).ConflictTreeMerger#visit_allnow resetslast_conflict_treewhen encountering a non-ConflictTreenode. Previously, this variable was never reset, causing non-adjacent ConflictTrees to be incorrectly merged together.For testing, this commit extends
test_merge_create_conflict_tree_constants_and_scopesto include a constantG = Cin LHS andclass G < B; endin RHS. The expected output now includes a conflict block for G showing both the constant assignment and class definition