Cannot define a specific branch as a requirement with composer

Question

I am having some trouble with using a specific branch as a dependency in my project.

I have one reposityry I'll call repositoryA which is the project I'm woring on, and repositoryB which is a different repository upon which repositoryA depends.

However, I have a specific branch in repositoryB named "1.0" that I want to specify for composer to use.

What I have tried in repositoryA is to, in composer.json, specify the following as a requirement (treat this as though each line is in different attempts, not in the same file/attempt):

// ...
"my-vendor/repositoryB": "1.0-dev",
"my-vendor/repositoryB": "1.0.x-dev",
"my-vendor/repositoryB": "dev-1.0",
"my-vendor/repositoryB": "dev-1.0.x",
"my-vendor/repositoryB": "1.0",
"my-vendor/repositoryB": "1.0.x",
// ...

When I try to set these constraints, then the error message I'm getting is:

The requested package my-vendor/repositoryB 1.0.x-dev exists as  
my-vendor/repositoryB[dev-master] but these are rejected by your constraint.

After googling this issue for a bit, it seemed like I need an alias for the "1.0"-branch for it to worked, so I also tried adding the following to the composer.json in repositoryB:

//...
"extra": {
  "branch-alias": {
    "1.0-dev": "1.0.x-dev"
  }
}
//...

What is it I'm misunderstanding in how this works?

Answer 1

I found a solution:

Turns out that I could get it to work by first updating the branch in composer.lock to 1.0.x-dev manually before running composer update.