Add a Blob struct

SwiftGit2/Objects.swift

@@ -223,3 +223,31 @@ extension Tree: Hashable {
 public func == (lhs: Tree, rhs: Tree) -> Bool {
 	return lhs.oid == rhs.oid
 }
+
+/// A git blob.
+public struct Blob: Object {
+	/// The OID of the blob.
+	public let oid: OID
+	
+	/// The contents of the blob.
+	public let data: NSData
+	
+	/// Create an instance with a libgit2 `git_blob`.
+	public init(pointer: COpaquePointer) {
+		oid = OID(oid: git_object_id(pointer).memory)
+		
+		// Swift doesn't get the types right without `Int(Int64(...))` :(
+		let length = Int(Int64(git_blob_rawsize(pointer).value))
+		data = NSData(bytes: git_blob_rawcontent(pointer), length: length)
+	}
+}
+
+extension Blob: Hashable {
+	public var hashValue: Int {
+		return oid.hashValue
+	}
+}
+
+public func == (lhs: Blob, rhs: Blob) -> Bool {
+	return lhs.oid == rhs.oid
+}

SwiftGit2/Repository.swift

@@ -57,6 +57,28 @@ final public class Repository {
 	public let directoryURL: NSURL?
 	
 	// MARK: - Object Lookups
+	
+	/// Loads the blob with the given OID.
+	///
+	/// oid - The OID of the blob to look up.
+	///
+	/// Returns the blob if it exists, or an error.
+	public func blobWithOID(oid: OID) -> Result<Blob> {
+		let pointer = UnsafeMutablePointer<COpaquePointer>.alloc(1)
+		let repository = self.pointer
+		var oid = oid.oid
+		let result = git_object_lookup(pointer, repository, &oid, GIT_OBJ_BLOB)
+		
+		if result < GIT_OK.value {
+			pointer.dealloc(1)
+			return failure()
+		}
+		
+		let commit = Blob(pointer: pointer.memory)
+		git_object_free(pointer.memory)
+		pointer.dealloc(1)
+		return success(commit)
+	}
 
 	/// Loads the commit with the given OID.
 	///

SwiftGit2Tests/ObjectsSpec.swift

@@ -279,3 +279,52 @@ class TreeSpec: QuickSpec {
 		}
 	}
 }
+
+class BlobSpec: QuickSpec {
+	override func spec() {
+		describe("init(pointer:)") {
+			it("should initialize its properties") {
+				let repo = Fixtures.simpleRepository
+				let oid = OID(string: "41078396f5187daed5f673e4a13b185bbad71fba")!
+				
+				let blob = from_git_object(repo, oid) { Blob(pointer: $0) }
+				let contents = "# Simple Repository\nA simple repository used for testing SwiftGit2.\n\n## Branches\n\n- master\n\n"
+				let data = (contents as NSString).dataUsingEncoding(NSUTF8StringEncoding)!
+				expect(blob.oid).to(equal(oid))
+				expect(blob.data).to(equal(data))
+			}
+		}
+		
+		describe("==") {
+			it("should be true with equal objects") {
+				let repo = Fixtures.simpleRepository
+				let oid = OID(string: "41078396f5187daed5f673e4a13b185bbad71fba")!
+				
+				let blob1 = from_git_object(repo, oid) { Blob(pointer: $0) }
+				let blob2 = blob1
+				expect(blob1).to(equal(blob2))
+			}
+			
+			it("should be false with unequal objects") {
+				let repo = Fixtures.simpleRepository
+				let oid1 = OID(string: "41078396f5187daed5f673e4a13b185bbad71fba")!
+				let oid2 = OID(string: "e69de29bb2d1d6434b8b29ae775ad8c2e48c5391")!
+				
+				let blob1 = from_git_object(repo, oid1) { Blob(pointer: $0) }
+				let blob2 = from_git_object(repo, oid2) { Blob(pointer: $0) }
+				expect(blob1).notTo(equal(blob2))
+			}
+		}
+		
+		describe("hashValue") {
+			it("should be equal with equal objects") {
+				let repo = Fixtures.simpleRepository
+				let oid = OID(string: "41078396f5187daed5f673e4a13b185bbad71fba")!
+				
+				let blob1 = from_git_object(repo, oid) { Blob(pointer: $0) }
+				let blob2 = blob1
+				expect(blob1.hashValue).to(equal(blob2.hashValue))
+			}
+		}
+	}
+}

SwiftGit2Tests/RepositorySpec.swift

@@ -26,6 +26,35 @@ class RepositorySpec: QuickSpec {
 			}
 		}
 		
+		describe("-blobWithOID()") {
+			it("should return the commit if it exists") {
+				let repo = Fixtures.simpleRepository
+				let oid = OID(string: "41078396f5187daed5f673e4a13b185bbad71fba")!
+				
+				let result = repo.blobWithOID(oid)
+				let blob = result.value()
+				expect(blob).notTo(beNil())
+				expect(blob?.oid).to(equal(oid))
+			}
+			
+			it("should error if the blob doesn't exist") {
+				let repo = Fixtures.simpleRepository
+				let oid = OID(string: "aaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaa")!
+				
+				let result = repo.blobWithOID(oid)
+				expect(result.error()).notTo(beNil())
+			}
+			
+			it("should error if the oid doesn't point to a blob") {
+				let repo = Fixtures.simpleRepository
+				// This is a tree in the repository
+				let oid = OID(string: "f93e3a1a1525fb5b91020da86e44810c87a2d7bc")!
+				
+				let result = repo.blobWithOID(oid)
+				expect(result.error()).notTo(beNil())
+			}
+		}
+		
 		describe("-commitWithOID()") {
 			it("should return the commit if it exists") {
 				let repo = Fixtures.simpleRepository