Sources/XCTest/Private/PrintObserver.swift

// This source file is part of the Swift.org open source project
//
// Copyright (c) 2016 Apple Inc. and the Swift project authors
// Licensed under Apache License v2.0 with Runtime Library Exception
//
// See http://swift.org/LICENSE.txt for license information
// See http://swift.org/CONTRIBUTORS.txt for the list of Swift project authors
//
//
//  PrintObserver.swift
//  Prints test progress to stdout.
//

/// Prints textual representations of each XCTestObservation event to stdout.
/// Mirrors the Apple XCTest output exactly.
internal class PrintObserver: XCTestObservation {
    func testBundleWillStart(_ testBundle: Bundle) {}

    func testSuiteWillStart(_ testSuite: XCTestSuite) {
        printAndFlush("Test Suite '\(testSuite.name)' started at \(dateFormatter.string(from: testSuite.testRun!.startDate!))")
    }

    func testCaseWillStart(_ testCase: XCTestCase) {
        printAndFlush("Test Case '\(testCase.name)' started at \(dateFormatter.string(from: testCase.testRun!.startDate!))")
    }

    func testCase(_ testCase: XCTestCase, didFailWithDescription description: String, inFile filePath: String?, atLine lineNumber: Int) {
        let file = filePath ?? "<unknown>"
        printAndFlush("\(file):\(lineNumber): error: \(testCase.name) : \(description)")
    }

    func testCaseDidFinish(_ testCase: XCTestCase) {
        let testRun = testCase.testRun!
        let verb = testRun.hasSucceeded ? "passed" : "failed"
        printAndFlush("Test Case '\(testCase.name)' \(verb) (\(formatTimeInterval(testRun.totalDuration)) seconds)")
    }

    func testSuiteDidFinish(_ testSuite: XCTestSuite) {
        let testRun = testSuite.testRun!
        let verb = testRun.hasSucceeded ? "passed" : "failed"
        printAndFlush("Test Suite '\(testSuite.name)' \(verb) at \(dateFormatter.string(from: testRun.stopDate!))")

        let tests = testRun.executionCount == 1 ? "test" : "tests"
        let failures = testRun.totalFailureCount == 1 ? "failure" : "failures"
        printAndFlush(
            "\t Executed \(testRun.executionCount) \(tests), " +
            "with \(testRun.totalFailureCount) \(failures) (\(testRun.unexpectedExceptionCount) unexpected) " +
            "in \(formatTimeInterval(testRun.testDuration)) (\(formatTimeInterval(testRun.totalDuration))) seconds"
        )
    }

    func testBundleDidFinish(_ testBundle: Bundle) {}

    private lazy var dateFormatter: DateFormatter = {
        let formatter = DateFormatter()
        formatter.dateFormat = "yyyy-MM-dd HH:mm:ss.SSS"
        return formatter
    }()

    fileprivate func printAndFlush(_ message: String) {
        print(message)
        #if !os(Android)
        fflush(stdout)
        #endif
    }

    private func formatTimeInterval(_ timeInterval: TimeInterval) -> String {
        return String(round(timeInterval * 1000.0) / 1000.0)
    }
}

extension PrintObserver: XCTestInternalObservation {
    func testCase(_ testCase: XCTestCase, didMeasurePerformanceResults results: String, file: StaticString, line: Int) {
        printAndFlush("\(file):\(line): Test Case '\(testCase.name)' measured \(results)")
    }
}