Cannot read Composer package from private hg repository on bitbucket - mercurial

Question

I am trying to use a Composer package from a private Mercurial repository on bitbucket. Composer says it can't find the package.
Let's call the package my-user/my-private-repo. For what it's worth, I've added my SSH public key to bitbucket for this repository. The composer.json file for the package looks like this:
{
"name": "my-user/my-private-repo",
"version": "0.0.1",
"description": "Some Composer Package",
"author": "me",
"license": "blah",
"require-dev": {
"phpunit/phpunit": "5.0.*"
}
}
And the composer.json for the project in which I want to use that package looks like:
{
"require": {
"my-user/my-private-repo": "^0.0.1"
},
"repositories": [
{
"type":"package",
"package":{
"name":"my-user/my-private-repo",
"version": "default",
"source":{
"type": "hg",
"url": "bitbucket.org/my-user/my-private-repo",
"reference":"default"
}
}
}
]
}
When I run composer update, I get the following error:
Loading composer repositories with package information
Updating dependencies (including require-dev)
Your requirements could not be resolved to an installable set of packages.
Problem 1
- The requested package my-user/my-private-repo could not be found in any version, there may be a typo in the package name.
Potential causes:
- A typo in the package name
- The package is not available in a stable-enough version according to your minimum-stability setting
see <https://groups.google.com/d/topic/composer-dev/_g3ASeIFlrc/discussion> for more details.
Read <https://getcomposer.org/doc/articles/troubleshooting.md> for further common problems.
I've read everything I can find on SO that seems relevant, but I can't seem to get past this error. How can I use my Composer package in a project?

Answer 1

Don't use the "package" type. This is only really useful for software that is NOT inside a repository. It is meant as a replacement to integrate ZIP downloads into Composer.
Additionally, it is complicated to collect all necessary info for that "package" type.
Repositories are way easier:
"repositories": [
{
"type": "vcs",
"url": "ssh://hg#bitbucket.org/my-user/my-private-repo"
}
]
The repository must have a valid composer.json file - and it really helps if it also has tagged versions, because dependencies using branches will break eventually because you cannot signal backward incompatible changes and cannot go back to a defined earlier version.
The composer.json MUST NOT have a version. That's what repository tags are for.
Note: The "type":"vcs" works generally well and will detect Git, Hg, or SVN repos.