vapor build command not working with Swift 3.0

Question

I am currently following the small and brief introduction to Swift Vapor by following their "Hello World" tutorial on their website. However I keep getting an error from swift-package when I try to build the project where it shows the following.

$ vapor build
No .build folder, fetch may take a while...
Fetching Dependencies [Failed]
Error: swift-package: error: unknown command: --enable-prefetching

I cannot seem to find out how to resolve this online. Anybody have any idea?

Answer 1

you have not mentioned your environment, so i'm giving solution for macOS.

I had the same issue, my swift version is 3.0.2 and vapor toolbox version is 1.0.9, I tried the following thing to make it work

1. get into your project directory

2. create xcode project with command

    swift package generate-xcodeproj 

3. open xcode project

4. Select your scheme as App like this

5. and then build and run app

hope this helps!!

Answer 2

Make sure that you're using the correct command line tools for the Swift Version that you're using.

You can check from Xcode > Preferences > Locations > Command Line Tools

Answer 3

For me, using swift 3.0.2, vapor build command doesn't work neither. However using swift 3.1.0, vapor build command works well. My Vapor toolbox version is v1.1.0

Answer 4

I had the same problem, and I had Swift 3.1 installed. I deleted old version completely and installed new one and now it's building fine.

Try

    rm -rf /usr/local/bin/vapor
    brew tap vapor/homebrew-tap
    


than

brew install vapor

or

brew link vapor

if you have installed a new version previously.