Allow filtering which tests are run (#4)

* Allow filtering which tests are run

* Fix Linux build

Author: harlanhaskins

Sources/LiteSupport/Run.swift

@@ -36,12 +36,14 @@ public func runLite(substitutions: [(String, String)],
                     testDirPath: String?,
                     testLinePrefix: String,
                     parallelismLevel: ParallelismLevel = .none,
-                    successMessage: String = "All tests passed! 🎉") throws -> Bool {
+                    successMessage: String = "All tests passed! 🎉",
+                    filters: [NSRegularExpression] = []) throws -> Bool {
   let testRunner = try TestRunner(testDirPath: testDirPath,
                                   substitutions: substitutions,
                                   pathExtensions: pathExtensions,
                                   testLinePrefix: testLinePrefix,
                                   parallelismLevel: parallelismLevel,
-                                  successMessage: successMessage)
+                                  successMessage: successMessage,
+                                  filters: filters)
   return try testRunner.run()
 }

Sources/LiteSupport/TestRunner.swift

@@ -56,13 +56,18 @@ class TestRunner {
   /// The message to print if all the tests passed.
   let successMessage: String
 
+  /// The set of filters to run over the file names, to refine which tests
+  /// are run.
+  let filters: [NSRegularExpression]
+
   /// Creates a test runner that will execute all tests in the provided
   /// directory.
   /// - throws: A LiteError if the test directory is invalid.
   init(testDirPath: String?, substitutions: [(String, String)],
        pathExtensions: Set<String>, testLinePrefix: String,
        parallelismLevel: ParallelismLevel,
-       successMessage: String) throws {
+       successMessage: String,
+       filters: [NSRegularExpression]) throws {
     let fm = FileManager.default
     var isDir: ObjCBool = false
     let testDirPath =
@@ -79,6 +84,7 @@ class TestRunner {
     self.testLinePrefix = testLinePrefix
     self.parallelismLevel = parallelismLevel
     self.successMessage = successMessage
+    self.filters = filters
   }
 
   func discoverTests() throws -> [TestFile] {
@@ -88,6 +94,14 @@ class TestRunner {
     var files = [TestFile]()
     for case let file as URL in enumerator {
       guard pathExtensions.contains(file.pathExtension) else { continue }
+      let nsPath = NSString(string: file.path)
+      let matchesFilter = filters.contains {
+        return $0.numberOfMatches(
+          in: file.path,
+          range: NSRange(location: 0, length: nsPath.length)
+        ) != 0
+      }
+      guard filters.isEmpty || matchesFilter else { continue }
       let runLines = try RunLineParser.parseRunLines(in: file,
                                                      prefix: testLinePrefix)
       if runLines.isEmpty { continue }

Sources/lite-test/main.swift

@@ -6,11 +6,12 @@ import LiteSupport
 
 /// Runs `lite` looking for `.test` files and executing them.
 do {
-  let allPassed = try runLite(substitutions: [("echo", "echo")],
-                              pathExtensions: ["test"],
-                              testDirPath: nil,
-                              testLinePrefix: "//",
-                              parallelismLevel: .automatic)
+  let allPassed = try runLite(
+    substitutions: [("echo", "echo")],
+    pathExtensions: ["test"],
+    testDirPath: nil,
+    testLinePrefix: "//",
+    parallelismLevel: .automatic)
   exit(allPassed ? 0 : -1)
 } catch let err as LiteError {
   fputs("error: \(err.message)", stderr)