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// This Source Code Form is subject to the terms of the Mozilla Public
// License, v. 2.0. If a copy of the MPL was not distributed with this
import XCTest
@testable import SiteImageView
final class LetterImageGeneratorTests: XCTestCase {
func testEmptyDomain_throws() async {
let subject = DefaultLetterImageGeneratorSpy()
let siteString = ""
do {
_ = try await subject.generateLetterImage(siteString: siteString)
} catch {
XCTAssertEqual(error.localizedDescription, SiteImageError.noLetterImage.localizedDescription)
}
}
func testDomain1_returnsExpectedLetterAndColor() async {
let subject = DefaultLetterImageGeneratorSpy()
let siteString = "mozilla.com"
do {
let result = try await subject.generateLetterImage(siteString: siteString)
XCTAssertEqual(subject.capturedLetter, "M")
XCTAssertNotEqual(result, UIImage())
testColor(subject: subject, red: 0.223, green: 0.576, blue: 0.125, alpha: 1.0)
} catch {
XCTFail("Failed to generate a letter image")
}
}
func testDomain2_returnsExpectedLetterAndColor() async {
let subject = DefaultLetterImageGeneratorSpy()
let siteString = "firefox.com"
do {
let result = try await subject.generateLetterImage(siteString: siteString)
XCTAssertEqual(subject.capturedLetter, "F")
XCTAssertNotEqual(result, UIImage())
testColor(subject: subject, red: 0.584, green: 0.803, blue: 1.0, alpha: 1.0)
} catch {
XCTFail("Failed to generate a letter image")
}
}
func testFakeDomain_returnsExpectedLetterAndColor() async {
let subject = DefaultLetterImageGeneratorSpy()
let siteString = "?$%^"
do {
let result = try await subject.generateLetterImage(siteString: siteString)
XCTAssertEqual(subject.capturedLetter, "?")
XCTAssertNotEqual(result, UIImage())
testColor(subject: subject, red: 0.003, green: 0.639, blue: 0.615, alpha: 1.0)
} catch {
XCTFail("Failed to generate a letter image")
}
}
}
// MARK: - Helper methods
private extension LetterImageGeneratorTests {
func testColor(subject: DefaultLetterImageGeneratorSpy,
red: CGFloat,
green: CGFloat,
blue: CGFloat,
alpha: CGFloat,
file: StaticString = #file,
line: UInt = #line) {
var resultRed: CGFloat = 0
var resultGreen: CGFloat = 0
var resultBlue: CGFloat = 0
var resultAlpha: CGFloat = 0
subject.capturedColor?.getRed(&resultRed,
green: &resultGreen,
blue: &resultBlue,
alpha: &resultAlpha)
XCTAssertEqual(resultRed, red, accuracy: 0.001, file: file, line: line)
XCTAssertEqual(resultGreen, green, accuracy: 0.001, file: file, line: line)
XCTAssertEqual(resultBlue, blue, accuracy: 0.001, file: file, line: line)
XCTAssertEqual(resultAlpha, alpha, accuracy: 0.001, file: file, line: line)
}
}
// MARK: - DefaultLetterImageGeneratorSpy
class DefaultLetterImageGeneratorSpy: DefaultLetterImageGenerator {
var capturedLetter: String?
var capturedColor: UIColor?
override func generateImage(fromLetter letter: String, color: UIColor) -> UIImage {
capturedLetter = letter
capturedColor = color
return super.generateImage(fromLetter: letter, color: color)
}
}