Specify dependency branch or commit ID in Swift PM's Package.swift

Question

Is there a way to define dependency in Package.swift that would point at a certain branch latest commit, or even to just a specific commit ID (just like it is possible with Carthage)?

Use case would be, let's say I have a library repo where I would like to branch out and make some changes, and then be able to test them out in a dependent project.

Answer 1

It is possible.

1. Go to project
2. Click on "Package Dependencies" Tab
3. Double click on the package you want to change the branch of
4. Specify the branch/commit.

Answer 2

As of Swift 4 you can use .branch() and .revision() as described in PackageDescription.md. 

Answer 3

Not yet, but swiftpm team is working on. Now you must specify a package version when declaring a dependency.

import PackageDescription

let package = Package(
    name: "Example",
    dependencies: [
        .Package(url: "https://github.com/somePackage", "1.0.0")
    ]
)

In the future it will be possible, there was a discussion to add Version Locking but its not accepted and implemented yet.

For your use case you can fork the repo, do the changes, test them and then add a version tag to your fork. Now it's much more easier to do changes with Editable Packages functionality.