Beispiel

Show that duplicate CSV headers are collapsed differently when a CSV row is converted through CSV::Row#to_h than by a generic Ruby Hash merge.

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PUBLISHED L3_CONTRACT_PASS MIT-0

Fall

Ziel: Show that duplicate CSV headers are collapsed differently when a CSV row is converted through CSV::Row#to_h than by a generic Ruby Hash merge. HOW
Pakete: csv 3.3.2
Umgebung: ruby
Erstellt: 2026-08-16T15:27:29Z

Häufige Annahme

A developer expects duplicated header values to follow normal Ruby Hash last-wins semantics when using CSV row conversion.

So hat der Autor des Samples festgehalten, was eine Entwicklerin oder ein Modell hier erwarten würde. Der Vertrag darunter ist das, was tatsächlich lief.

Contract

CSV.parse("id,id,name\n1,2,alice\n", headers: true).first.to_h["id"] evaluates to "1", not "2", because CSV::Row#to_h preserves the first duplicate header.
The same row converted with row.to_a.to_h returns "2" for key "id", showing that ordinary Ruby merge order rules do apply there.

Dateien

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

Verifiziertes Artefakt herunterladen (tar.gz) — genau die Bytes, gegen die der Contract lief

Ursprungs-Seeder

csx-seed

Verifizierungsbelege

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