BDD Framework and test runner for Swift projects and playgrounds
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Special Executive for Command-line Test Running and Execution.

A behavior-driven development (BDD) framework and test runner for Swift projects and playgrounds. It's compatible with both OS X and Linux.


describe("a person") {
  let person = Person(name: "Kyle")

  $"has a name") {
    try expect( == "Kyle"

  $"returns the name as description") {
    try expect(person.description) == "Kyle"


Spectre currently has two built-in reporters, Standard and the Dot reporter. Custom reporters are supported, simply make a type that conforms to Reporter.


The standard reporter produces output as follows:

Passing Tests

Standard Reporter Success

Failing Tests

Standard Reporter Failure


Using the -t argument, you can use the dot reporter.

Passing Tests

Dot Reporter Success

Failing Tests

Dot Reporter Failure



try expect(name) == "Kyle"
try expect(name) != "Kyle"


try expect(alive).to.beTrue()
try expect(alive).to.beFalse()
try expect(alive).to.beNil()

Error handling

try expect(try write()).toThrow()
try expect(try write()).toThrow(FileError.NoPermission)


try expect(5) > 2
try expect(5) >= 2
try expect(5) < 10
try expect(5) <= 10


try expect("kyle").to.beOfType(String.self)

Causing a failure

throw failure("Everything is broken.")

Custom assertions

You can easily provide your own assertions, you just need to throw a failure when the assertion does not meet expectaions.


The following projects use Spectre:

Project CI
Stencil Build Status
Inquiline Build Status
CardKit Build Status

Installation / Running


Check out spectre-build.


Conche build system has integrated support for Spectre. You can simply add a test_spec to your Conche podspec depending on Spectre and it will run your tests with conche test.


You can use Spectre in an Xcode Playground, open Spectre.playground in this repository, failures are printed in the console.

Spectre in an Xcode Playground


You can build Spectre as a Framework or a library and link against it.

For example, if you clone Spectre and run make it will build a library you can link against:

$ swiftc -I .conche/modules -L .conche/lib -lSpectre -o runner myTests.swift
$ ./runner