Sample YAML file: free download
What is a YAML file?
YAML is an indentation-based data format used widely for configuration. YAML 1.2 is almost a superset of JSON, but many parsers still follow YAML 1.1, where unquoted values such as no, yes, on and off become booleans. That is why the country code NO turns into false.
YAML files including the famous Norway problem, where an unquoted country code is parsed as a boolean.
2 ready-made YAML test files
| File | Size | What it catches | Download |
|---|---|---|---|
| tabs-invalid.yaml | 34 bytes | Config loaders whose error message just says "unexpected character" without pointing at the tab. A very common source of confusing CI failures. | download |
| norway-problem.yaml | 161 bytes | The famous "Norway problem" - a country list where NO silently becomes boolean false. Also catches version: 1.10 collapsing to 1.1. Parsers on YAML 1.2 core schema behave differently, so this file also reveals which spec version your library actually implements. | download |
Every file is generated from source (no third-party copyright) and each has its own page with a published SHA-256 you can verify after download.
Questions
What is the YAML Norway problem?
In YAML 1.1, the unquoted value NO is parsed as the boolean false, so a list of country codes silently turns Norway into false. The file below reproduces it along with the other implicit-typing traps.