[SourceControl] Add RepositorySpecifier: Hashable.

Author: ddunbar

Sources/SourceControl/Repository.swift

@@ -11,7 +11,7 @@
 import Basic
 
 /// Specifies a repository address.
-public struct RepositorySpecifier {
+public struct RepositorySpecifier: Hashable {
     /// The URL of the repository.
     public let url: String
 
@@ -31,6 +31,13 @@ public struct RepositorySpecifier {
         let basename = url.components(separatedBy: "/").last!
         return basename + "-" + String(url.hashValue)
     }
+
+    public var hashValue: Int {
+        return url.hashValue
+    }
+}
+public func ==(lhs: RepositorySpecifier, rhs: RepositorySpecifier) -> Bool {
+    return lhs.url == rhs.url
 }
 
 /// A repository provider.

Tests/SourceControlTests/GitRepositoryTests.swift

@@ -19,6 +19,17 @@ import TestSupport
 @testable import class SourceControl.GitRepository
 
 class GitRepositoryTests: XCTestCase {
+    /// Test the basic provider functions.
+    func testRepositorySpecifier() {
+        let a = RepositorySpecifier(url: "a")
+        let b = RepositorySpecifier(url: "b")
+        let a2 = RepositorySpecifier(url: "a")
+        XCTAssertEqual(a, a)
+        XCTAssertNotEqual(a, b)
+        XCTAssertEqual(a, a2)
+        XCTAssertEqual(Set([a]), Set([a2]))
+    }
+        
     /// Test the basic provider functions.
     func testProvider() throws {
         mktmpdir { path in
@@ -185,6 +196,7 @@ class GitRepositoryTests: XCTestCase {
     }
 
     static var allTests = [
+        ("testRepositorySpecifier", testRepositorySpecifier),
         ("testProvider", testProvider),
         ("testGitRepositoryHash", testGitRepositoryHash),
         ("testRawRepository", testRawRepository),