add testing

Package.swift

@@ -16,6 +16,8 @@ let package = Package(
                 dependencies: ["CBacktrace"]),
         .target(name: "CBacktrace",
                 dependencies: []),
+        .target(name: "Sample",
+                dependencies: ["Backtrace"]),
         .testTarget(name: "BacktraceTests",
                     dependencies: ["Backtrace"]),
     ]

Sources/Sample/main.swift

@@ -0,0 +1,19 @@
+//===----------------------------------------------------------------------===//
+//
+// This source file is part of the SwiftLinuxBacktrace open source project
+//
+// Copyright (c) 2019-2020 Apple Inc. and the SwiftLinuxBacktrace project authors
+// Licensed under Apache License v2.0
+//
+// See LICENSE.txt for license information
+// See CONTRIBUTORS.txt for the list of SwiftLinuxBacktrace project authors
+//
+// SPDX-License-Identifier: Apache-2.0
+//
+//===----------------------------------------------------------------------===//
+
+import Backtrace
+
+let reason = CommandLine.arguments.count == 2 ? CommandLine.arguments[1] : "unknown"
+Backtrace.install()
+fatalError(reason)

Tests/BacktraceTests/BacktraceTests+XCTest.swift

@@ -23,9 +23,9 @@ import XCTest
 ///
 
 extension BacktraceTests {
-    static var allTests: [(String, (BacktraceTests) -> () throws -> Void)] {
+    public static var allTests: [(String, (BacktraceTests) -> () throws -> Void)] {
         return [
-            ("testExample", testExample),
+            ("testBacktrace", testBacktrace),
         ]
     }
 }

Tests/BacktraceTests/BacktraceTests.swift

@@ -12,14 +12,25 @@
 //
 //===----------------------------------------------------------------------===//
 
-@testable import Backtrace
 import XCTest
 
-final class BacktraceTests: XCTestCase {
-    func testExample() {
-        // This is an example of a functional test case.
-        // Use XCTAssert and related functions to verify your tests produce the correct
-        // results.
-        XCTAssert(true)
+public final class BacktraceTests: XCTestCase {
+    func testBacktrace() {
+        #if os(Linux)
+        let expectedError = UUID().uuidString
+        let pipe = Pipe()
+        let process = Process()
+        process.executableURL = URL(fileURLWithPath: "/usr/bin/swift")
+        process.arguments = ["run", "Sample", expectedError]
+        process.standardError = pipe
+        XCTAssertNoThrow(try process.run())
+        if process.isRunning {
+            process.waitUntilExit()
+        }
+        let stderr = String(data: pipe.fileHandleForReading.readDataToEndOfFile(), encoding: .utf8) ?? ""
+        print(stderr)
+        XCTAssert(stderr.contains("Current stack trace:"), "expected stanard error to include backtrace")
+        XCTAssert(stderr.contains("Fatal error: \(expectedError)"), "expected stanard error to include error information")
+        #endif
     }
 }

Tests/LinuxMain.swift

@@ -23,7 +23,7 @@ import XCTest
 ///
 
 #if os(Linux) || os(FreeBSD)
-@testable import BacktraceTests
+import BacktraceTests
 
 XCTMain([
     testCase(BacktraceTests.allTests),

docker/docker-compose.yaml

@@ -28,7 +28,7 @@ services:
 
   test:
     <<: *common
-    command: /bin/bash -cl "swift test -Xswiftc -warnings-as-errors $${SANITIZER_ARG-}"
+    command: /bin/bash -cl "swift test -c release -Xswiftc -g -Xswiftc -warnings-as-errors $${SANITIZER_ARG-}"
 
   # util
 

scripts/generate_linux_tests.rb

@@ -72,7 +72,7 @@ def createExtensionFile(fileName, classes)
 
     for classArray in classes
       file.write 'extension ' + classArray[0] + " {\n"
-      file.write '    static var allTests: [(String, (' + classArray[0] + ") -> () throws -> Void)] {\n"
+      file.write '    public static var allTests: [(String, (' + classArray[0] + ") -> () throws -> Void)] {\n"
       file.write "        return [\n"
 
       for funcName in classArray[1]
@@ -96,7 +96,7 @@ def createLinuxMain(testsDirectory, allTestSubDirectories, files)
 
     file.write "#if os(Linux) || os(FreeBSD)\n"
     for testSubDirectory in allTestSubDirectories.sort { |x, y| x <=> y }
-      file.write '@testable import ' + testSubDirectory + "\n"
+      file.write 'import ' + testSubDirectory + "\n"
     end
     file.write "\n"
     file.write "XCTMain([\n"