QuickStart contribution

Configure the system
Build Swift Compiler
Build swift-corelibs-foundation
Starter Bugs

Configure the system

Requirements

macOS 10.14.4 or later
Xcode 11 beta 1
60 GB of free disk space

Install Xcode

Download Xcode 11 beta 1 and select Applications
Double click on the XIP image
Move the Xcode-beta.app to /Applications/

mv ~/Downloads/Xcode-beta.app /Applications/

xcode-select the Xcode 11 beta 1

xcode-select -s /Applications/Xcode-beta.app

Install CMake and Ninja

Install CMake using package manager [1]
Homebrew

brew install cmake ninja

MacPorts

port install cmake ninja

Setup Swift Repositories

Clone Swift repository

git clone git@github.com:apple/swift.git

Clone other required repositories

./swift/utils/update-checkout --clone --scheme master

Build Swift Compiler

Build Swift compiler without additional tools

Build Swift Compiler:

./swift/utils/build-script --build-ninja --release-debuginfo

Build Swift Compiler with Sccache

Install sccache using Homebrew [2]

brew install sccache

Set sccache server URL

export SCCACHE_REDIS=${SCCACHE_REDIS}

Start sccache server

sccache  --start-server

Build Swift Compiler:

./swift/utils/build-script \
    --cmake-c-launcher `which sccache` \
    --cmake-cxx-launcher `which sccache` \
    --preset=buildbot_incremental,tools=RA,stdlib=RD,build

Stop sccache server

sccache  --stop-server

Build Swift stdlib against a downloadable toolchain

Create a workspace directory

mkdir workspace
cd workspace

Download the following snapshot from swift.org: https://swift.org/builds/development/xcode/swift-DEVELOPMENT-SNAPSHOT-2019-06-06-a/swift-DEVELOPMENT-SNAPSHOT-2019-06-06-a-osx.pkg

curl -O https://swift.org/builds/development/xcode/swift-DEVELOPMENT-SNAPSHOT-2019-06-06-a/swift-DEVELOPMENT-SNAPSHOT-2019-06-06-a-osx.pkg

Untar the file using the commands into workspace/toolchain

mkdir toolchain
xar -C toolchain -x -f swift-DEVELOPMENT-SNAPSHOT-2019-06-06-a-osx.pkg
tar -C toolchain -xzf toolchain/swift-DEVELOPMENT-SNAPSHOT-2019-06-06-a-osx-package.pkg/Payload
TOOLCHAIN_BIN_DIR=$PWD/toolchain/usr/bin

Clone Swift repository:

git clone git@github.com:apple/swift.git

Clone other required repositories:

./swift/utils/update-checkout --clone --scheme=stdlib_standalone

Build the swift stdlib using one of the presets from the chart below. We suggest for development to try stdlib_DA_standalone,build. The form of the build-script invocation is:
- To build/test
  
  ./swift/utils/build-script --preset=$PRESET_NAME toolchain_path=$TOOLCHAIN_BIN_DIR
- To reconfigure (rerun cmake), pass in the reconfigure flag.
  
  ./swift/utils/build-script --preset=$PRESET_NAME toolchain_path=$TOOLCHAIN_BIN_DIR --reconfigure
- Example:
  
  ./swift/utils/build-script --preset=stdlib_DA_standalone,build toolchain_path=$TOOLCHAIN_BIN_DIR
- To clean remove ./workspace/build/$PRESET_STEM. Example:
  
  rm -rfv build/stdlib_DA_standalone

Preset `$PRESET_NAME`	Build Type	Test	Debug Info
`stdlib_DA_standalone,build`	Debug	No	Yes
`stdlib_DA_standalone,build,test`	Debug	Yes	Yes
`stdlib_RA_standalone,build`	Release	No	No
`stdlib_RA_standalone,build,test`	Release	Yes	No
`stdlib_RDA_standalone,build`	Release	No	Yes
`stdlib_RDA_standalone,build,test`	Release	Yes	Yes

Build swift-corelibs-foundation

build swift-corelibs-foundation against a downloadable toolchain

Download and install the latest trunk snapshot using the Installer app from swift.org
Clone Swift repository

git clone git@github.com:apple/swift.git

Clone other required repositories

./swift/utils/update-checkout --clone --scheme master

Open the Xcode version you just installed; select from the menu Xcode > Preferences > Components > Toolchains and enable the trunk snapshot you installed.
Open Foundation.xcworkspace from the swift-corelibs-foundation repository from that version of Xcode.
Build and run the TestFoundation scheme.

[1] Manually install CMake

Download CMake
Install CMake

mkdir -p $HOME/bin
tar xfz cmake-3.14.4-Darwin-x86_64.tar.gz -C $HOME/bin
export PATH=$HOME/bin/cmake-3.14.4-Darwin-x86_64/CMake.app/Contents/bin:$PATH

[2] Manually Install Sccache:

Download sccache
Install sccache

mkdir -p $HOME/bin
tar xfz sccache-0.2.8-x86_64-apple-darwin.tar.gz -C $HOME/bin
export PATH=$HOME/bin/sccache-0.2.8-x86_64-apple-darwin:$PATH

Starter bugs

The Swift project uses JIRA for bug tracking and the bugs and enhancement requests could be found at bugs.swift.org. If you are new to the codebase, you can identify beginner tasks by searching for the bugs that have the “Starter Bug” label. Here are some beginner bugs that you can start with with today.

Swift Compiler

SR-10292: Missing fix-it to add ‘override’ keyword while trying to override a computed property
SR-9679: Spurious “enum element cannot be referenced as an instance member” error
SR-9040: Suggestion when overriding implictly unwrapped optional does not suggest making parameter implictly unwrapped
SR-9615: @escaping and inout should work together but don’t
SR-8797: Misleading diagnostic when closure parameter is missing

Standard Library

SR-8905: Gaps in String benchmarking
SR-10817: Gaps in arithmetic benchmarking / testing

LLDB

SR-10584: REPL crashes when triggering code completion with tab
SR-5994: Off by one error in URL description data formatter
SR-6189: Wrong values being printed when using protocols
SR-6657: Couldn’t load ‘self’ because its value couldn’t be evaluated
SR-6156: Expression parser fails to evaluate member variable
SR-1350: REPL doesn’t correctly handle guard variable shadowing

SourceKit-LSP

SR-10806: workspace/symbol (open quickly)
SR-10807: textDocument/typeDefinition
SR-10808: textDocument/implementation (find impls of protocol)
SR-10809: Honour ClientCapabilities for code completion snippets

bugs.swift.org:

component: SourceKit-LSP, label: StarterBug
component: SwiftSyntax, label: StarterBug

Swift Package Manager

SR-10794: Have SwiftPM suggest close commands
SR-10633: SwiftPM can’t find its own clang
SR-7828: Include name-based “fixits” whenever we do a unique name membership lookup
SR-20: Update swift –help to explain multitool support (“swift build”, etc.)
SR-9402: SwiftPM should diagnose duplicate target dependency declarations and emit a warning
SR-10616: SwiftPM: cross compilation broken in Swift 5.0.1
SR-10802: –disable-automatic-resolution doesn’t work with local packages
SR-10804: Add $(inherited) to OTHER_SWIFT_FLAGS
SR-10805: The root property in PackageModel.Sources struct should use the directory name as on disk
SR-10799: SwiftPM should have a –no-network flag that ensures no network calls are made
SR-10800: swift test should have more flexible test selection
SR-10801: swift test --filter should display summary for the entire group of tests run, not per-test
SR-10803: Descriptive Help for “swift package init –type” in SPM

Swift Infrastructure

SR-10824: Add support for XML test results to source compatibility suite
SR-10810: Create preset for LLDB macOS bots
SR-10825: Profile building and testing Swift compiler
SR-10827: Add test suite to swift-docker

Swift Corelibs Foundation

SR-10347: Parity Remove all uses of NSUnimplemented from swift-corelibs-foundation