FA-75629 / Text diff and three-way merge / Member archive

Merge base selection: the oldest common ancestors are kept instead of the newest · case 04

The merge base is the root commit, so merges show every change since the beginning of history.

Member previewVariant 4 · 3 implementations · 10 checks per implementation

Case contract

Given a commit graph (commit -> parent list) and two commits, ancestors include the commit itself and all commits reachable through any parent. The merge bases are the common ancestors that are not ancestors of another common ancestor. Return them sorted.

Why this case matters

A three-way merge is only as good as its base; criss-cross histories legitimately have several best common ancestors.

One recorded failure

Sample boundary fixture

This sample comes from the broken implementation of a controlled reproducer.

Boundary fixture	Actual	Expected	Outcome
simple fork	`["A"]`	`["B"]`	Failed

MEMBER ARCHIVE

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