T-208: Fix random_topology_tree ignoring constraints#219
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ms609 wants to merge 1 commit intocpp-searchfrom
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T-208: Fix random_topology_tree ignoring constraints#219ms609 wants to merge 1 commit intocpp-searchfrom
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…e (T-208) When adaptiveStart=TRUE and constraints are active, the bandit could select RANDOM_TREE, which calls random_topology_tree() without constraint data. The resulting starting tree may violate constraints, causing TBR to block all constraint-relevant moves (cn=-1). Fix: fall back to random_wagner_tree(tree, ds, cd) when RANDOM_TREE is selected and cd->active is true. This preserves the random-start exploration intent while respecting topological constraints. Test: added adaptiveStart + constraint test (8 replicates).
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ms609
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Verifies all output trees satisfy constraints when adaptiveStart=TRUE forces RANDOM_TREE strategy with active constraints. Tests the random_constrained_tree() polytomy-resolution path on cpp-search. PR #219 is now superseded (its code fix replaced by random_constrained_tree on cpp-search); this preserves its test.
ms609
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- Close T-208 (cherry-picked to cpp-search, PR #219 closed) - Close T-211 (conservative-only impact, not worth fixing) - Add T-213 (impose_constraint, PARKED) and T-214 (multi-split bug) - Update T-212 status (tests committed, new GHA after heredoc fix) - Remove stray EOF heredoc artifacts from completed-tasks.md - Add S-PR to standing tasks
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Agent G.
Bug: When
adaptiveStart=TRUE(thorough preset) and constraints active, the bandit could selectRANDOM_TREE, which callsrandom_topology_tree()withoutConstraintData. The resulting starting tree may violate constraints, causing TBR to block all constraint-relevant moves (cn=-1). Could return constraint-violating trees.Fix: Fall back to
random_wagner_tree(tree, ds, cd)whenRANDOM_TREEis selected andcd->activeis true. Preserves random-start exploration intent while respecting constraints.Test: Added
adaptiveStart + constrainttest (8 replicates, 4 target hits).GHA: Run 23506900264 — PASS (Ubuntu ARM64 + Windows).