Yamelot includes test specs to be used to validate all implementations. A general purpose test framework is written in python; each implementation plugs in via a simple stdin/stdout interface. Implementations are plugged in via a python/integration_runner.{which} executable file.

The following steps should prepare the validation framework to run. (Each implementation may have its own build and dep process; these should be covered in their individual READMEs.)

# clone!
git clone https://github.com/gnprice/yamelot.git
cd yamelot

# get virtualenv
# for linux, this is:
apt-get install virtualenv

# whip up a clean env
virtualenv env
. ./env/bin/activate
pip install pytest

# run tests!
# drop the "-k {thingy}" part to run all impls.
py.test -k libyaml

libyaml in this example may be replaced by any other suffix of the integration_runner files.

Yamelot is a subset of YAML. See the YAML spec for details of YAML syntax. Yamelot differs from YAML in the following ways:

• No tags! This means no referring to arbitrary application data types, which means no executing arbitrary code in loading a Yamelot document.
• UTF-8 always
• No BOM
• No schemas
• No cycles
• Anchors must be globally unique within a document, scoped to document
• No octal (give an error)
• No binary
• No folded scalars (>)
• No chomping indicators (-/+)
• No ~ for null, no empty nodes (except empty nodes as mapping values)
• No explicit keys (?)
• No "default" mapping values (=)
• No multiline bare scalars
• No y/Y/n/N booleans
• No base-60 numbers

We contemplate a gofmt-like tool for canonicalizing the style of Yamelot documents. The following YAML features will likely be canonicalized away by such a tool, though they remain part of Yamelot:

• Single-quoted strings
• Directives
• Empty nodes as mapping values (canonicalize to explicit null)

Yamelot retains all other features of YAML unchanged. In particular this includes the following:

• Anchor, alias, merge
• In-order reference resolution (anchor must appear before reference)
• Spaces-only for indentation
• Indentation annotation for literal blocks
• Arbitrarily large integers
• Timestamps
• Streams and document start/end indicators (---, ...)
• The indicator characters @ and "`" are reserved