サンプル

Set#divide with a 2-arity block applies transitive closure (union-find) across all element pairs, not pairwise grouping, so elements connected through intermediaries collapse into one partition

sha256:081685a24f8921c237110315b32c09809d9d3c38413eb03da335108348d877e8

ケース

ゴール

Set#divide with a 2-arity block applies transitive closure (union-find) across all element pairs, not pairwise grouping, so elements connected through intermediaries collapse into one partition HOW

パッケージ

set 1.1.1

環境

ruby

作成日

2026-08-16T16:53:43Z

よくある思い込み

Set#divide with a 2-arity predicate block partitions elements by directly evaluating the block on every pair and grouping each matching pair together, so Set[1,2,3,4].divide { |a,b| (a-b).abs == 1 } produces multiple partitions matching the adjacent pairs rather than collapsing all transitively-connected elements into one.

このサンプルの作者が、ここで開発者やモデルが期待するであろうこととして記録したもの。下の契約が実際に実行されたものだ。

コントラクト

• Set[1,2,3,4].divide { |a,b| (a-b).abs == 1 } returns a single partition containing all four elements rather than multiple pairwise groups, because the 2-arity form performs a transitive-closure (union-find) over all pairs, merging 1-2, 2-3, and 3-4 into one equivalence class
• assert result.size == 1 and result.first == Set[1,2,3,4]
• assert adding an isolated element (100) produces exactly two partitions: {1,2,3,4} and {100}
• assert Set#divide returns a Set of Sets while Set#classify returns a Hash keyed by block return value — they are not interchangeable
• assert Set#divide with a 1-arity block groups by block return value without transitivity, yielding as many partitions as there are distinct block values
• assert Set#divide on an empty Set returns an empty Set, not nil

ファイル

• Gemfile
• Gemfile.lock
• NOTES.md
• csx.json
• test/contract.rb

検証済みアーティファクトをダウンロード (tar.gz) — 契約が実行された正確なバイト列

オリジンシーダー

csx-seed

検証レシート

• ruby 3 · CONTAINER_RUN · compile:SKIPPED · contract:PASS · load:PASS · resolve:PASS · rubygems@1 · 2026-08-16 · ed25519:d91480838ac982c9