Error handling #10

CSVConfiguration.swift

@@ -16,6 +16,8 @@ internal let defaultWhitespaces = CharacterSet.whitespaces
 /// No overview available.
 public struct CSVConfiguration {
 
+    public var errorHandler: ((Error, Int, Int) -> Void)? = nil
+
     /// `true` if the CSV has a header row, otherwise `false`. Default: `false`.
     public let hasHeaderRow: Bool
     /// No overview available.

Sources/BinaryReader.swift

@@ -164,21 +164,23 @@ internal class BinaryReader {
 
 extension BinaryReader {
 
-    internal struct UInt8Iterator: Sequence, IteratorProtocol {
+    internal class UInt8Iterator: Sequence, IteratorProtocol {
 
         private let reader: BinaryReader
+        internal var errorHandler: ((Error) -> Void)? = nil
 
         fileprivate init(reader: BinaryReader) {
             self.reader = reader
         }
 
-        internal mutating func next() -> UInt8? {
+        internal func next() -> UInt8? {
             if !reader.hasBytesAvailable {
                 return nil
             }
             do {
                 return try reader.readUInt8()
             } catch {
+                errorHandler?(error)
                 return nil
             }
         }
@@ -193,21 +195,23 @@ extension BinaryReader {
 
 extension BinaryReader {
 
-    internal struct UInt16Iterator: Sequence, IteratorProtocol {
+    internal class UInt16Iterator: Sequence, IteratorProtocol {
 
         private let reader: BinaryReader
+        internal var errorHandler: ((Error) -> Void)? = nil
 
         fileprivate init(reader: BinaryReader) {
             self.reader = reader
         }
 
-        internal mutating func next() -> UInt16? {
+        internal func next() -> UInt16? {
             if !reader.hasBytesAvailable {
                 return nil
             }
             do {
                 return try reader.readUInt16()
             } catch {
+                errorHandler?(error)
                 return nil
             }
         }
@@ -222,21 +226,23 @@ extension BinaryReader {
 
 extension BinaryReader {
 
-    internal struct UInt32Iterator: Sequence, IteratorProtocol {
+    internal class UInt32Iterator: Sequence, IteratorProtocol {
 
         private let reader: BinaryReader
+        internal var errorHandler: ((Error) -> Void)? = nil
 
         fileprivate init(reader: BinaryReader) {
             self.reader = reader
         }
 
-        internal mutating func next() -> UInt32? {
+        internal func next() -> UInt32? {
             if !reader.hasBytesAvailable {
                 return nil
             }
             do {
                 return try reader.readUInt32()
             } catch {
+                errorHandler?(error)
                 return nil
             }
         }

Sources/CSV+init.swift

@@ -15,7 +15,7 @@ extension CSV {
     /// - parameter stream: An `InputStream` object. If the stream is not open,
     ///                     initializer opens automatically.
     /// - parameter config: CSV configuration.
-    public init(
+    public convenience init(
         stream: InputStream,
         config: CSVConfiguration = CSVConfiguration()) throws {
 
@@ -30,7 +30,7 @@ extension CSV {
     ///
     /// - parameter string: An CSV string.
     /// - parameter config: CSV configuration.
-    public init(
+    public convenience init(
         string: String,
         config: CSVConfiguration = CSVConfiguration()) throws {
 

Sources/CSV+iterator.swift

@@ -9,7 +9,7 @@
 extension CSV: IteratorProtocol, Sequence {
 
     /// No overview available.
-    public mutating func next() -> Row? {
+    public func next() -> Row? {
         guard let row = readRow() else {
             return nil
         }

Sources/CSV.swift

@@ -13,13 +13,16 @@ private let CR = UnicodeScalar(UInt8(0x0d))     // "\r"
 private let DQUOTE = UnicodeScalar(UInt8(0x22)) // "\""
 
 /// No overview available.
-public struct CSV {
+public class CSV {
 
     private var iterator: AnyIterator<UnicodeScalar>
     private let config: CSVConfiguration
 
     private var back: UnicodeScalar? = nil
 
+    private var currentRowIndex: Int = 0
+    private var currentFieldIndex: Int = 0
+
     /// CSV header row. To set a value for this property,
     /// you set `true` to `hasHeaerRow` in initializer.
     public private(set) var headerRow: [String]? = nil
@@ -46,18 +49,18 @@ public struct CSV {
     ///                     initializer opens automatically.
     /// - parameter codecType: A `UnicodeCodec` type for `stream`.
     /// - parameter config: CSV configuration.
-    public init<T: UnicodeCodec>(
+    public convenience init<T: UnicodeCodec>(
         stream: InputStream,
         codecType: T.Type,
         config: CSVConfiguration = CSVConfiguration()
         ) throws where T.CodeUnit == UInt8 {
 
         let reader = try BinaryReader(stream: stream, endian: .unknown, closeOnDeinit: true)
-        let iterator = UnicodeIterator(
+        let input = reader.makeUInt8Iterator()
-            input: reader.makeUInt8Iterator(),
+        let iterator = UnicodeIterator(input: input, inputEncodingType: codecType)
-            inputEncodingType: codecType
-        )
         try self.init(iterator: iterator, config: config)
+        input.errorHandler = self.errorHandler
+        iterator.errorHandler = self.errorHandler
     }
 
     /// Create an instance with `InputStream`.
@@ -67,7 +70,7 @@ public struct CSV {
     /// - parameter codecType: A `UnicodeCodec` type for `stream`.
     /// - parameter endian: Endian to use when reading a stream. Default: `.big`.
     /// - parameter config: CSV configuration.
-    public init<T: UnicodeCodec>(
+    public convenience init<T: UnicodeCodec>(
         stream: InputStream,
         codecType: T.Type,
         endian: Endian = .big,
@@ -75,11 +78,11 @@ public struct CSV {
         ) throws where T.CodeUnit == UInt16 {
 
         let reader = try BinaryReader(stream: stream, endian: endian, closeOnDeinit: true)
-        let iterator = UnicodeIterator(
+        let input = reader.makeUInt16Iterator()
-            input: reader.makeUInt16Iterator(),
+        let iterator = UnicodeIterator(input: input, inputEncodingType: codecType)
-            inputEncodingType: codecType
-        )
         try self.init(iterator: iterator, config: config)
+        input.errorHandler = self.errorHandler
+        iterator.errorHandler = self.errorHandler
     }
 
     /// Create an instance with `InputStream`.
@@ -89,7 +92,7 @@ public struct CSV {
     /// - parameter codecType: A `UnicodeCodec` type for `stream`.
     /// - parameter endian: Endian to use when reading a stream. Default: `.big`.
     /// - parameter config: CSV configuration.
-    public init<T: UnicodeCodec>(
+    public convenience init<T: UnicodeCodec>(
         stream: InputStream,
         codecType: T.Type,
         endian: Endian = .big,
@@ -97,16 +100,18 @@ public struct CSV {
         ) throws where T.CodeUnit == UInt32 {
 
         let reader = try BinaryReader(stream: stream, endian: endian, closeOnDeinit: true)
-        let iterator = UnicodeIterator(
+        let input = reader.makeUInt32Iterator()
-            input: reader.makeUInt32Iterator(),
+        let iterator = UnicodeIterator(input: input, inputEncodingType: codecType)
-            inputEncodingType: codecType
-        )
         try self.init(iterator: iterator, config: config)
+        input.errorHandler = self.errorHandler
+        iterator.errorHandler = self.errorHandler
     }
 
     // MARK: - Parse CSV
 
-    internal mutating func readRow() -> [String]? {
+    internal func readRow() -> [String]? {
+        currentFieldIndex = 0
+
         var c = moveNext()
         if c == nil {
             return nil
@@ -140,13 +145,18 @@ public struct CSV {
             if end {
                 break
             }
+
+            currentFieldIndex += 1
+
             c = moveNext()
         }
 
+        currentRowIndex += 1
+
         return row
     }
 
-    private mutating func readField(quoted: Bool) -> (String, Bool) {
+    private func readField(quoted: Bool) -> (String, Bool) {
         var field = ""
 
         while let c = moveNext() {
@@ -206,7 +216,7 @@ public struct CSV {
         return (field, true)
     }
 
-    private mutating func moveNext() -> UnicodeScalar? {
+    private func moveNext() -> UnicodeScalar? {
         if back != nil {
             defer {
                 back = nil
@@ -216,13 +226,15 @@ public struct CSV {
         return iterator.next()
     }
 
-}
+    private func errorHandler(error: Error) {
+        config.errorHandler?(error, currentRowIndex, currentFieldIndex)
+    }
 
-extension CSV {
+    // MARK: - deprecated
 
     /// Unavailable.
     @available(*, unavailable, message: "Use init(stream:codecType:config:) instead")
-    public init<T: UnicodeCodec>(
+    public convenience init<T: UnicodeCodec>(
         stream: InputStream,
         codecType: T.Type,
         hasHeaderRow: Bool = defaultHasHeaderRow,
@@ -245,7 +257,7 @@ extension CSV {
 
     /// Unavailable.
     @available(*, unavailable, message: "Use init(stream:codecType:endian:config:) instead")
-    public init<T: UnicodeCodec>(
+    public convenience init<T: UnicodeCodec>(
         stream: InputStream,
         codecType: T.Type,
         endian: Endian = .big,
@@ -269,7 +281,7 @@ extension CSV {
 
     /// Unavailable.
     @available(*, unavailable, message: "Use init(stream:codecType:endian:config:) instead")
-    public init<T: UnicodeCodec>(
+    public convenience init<T: UnicodeCodec>(
         stream: InputStream,
         codecType: T.Type,
         endian: Endian = .big,
@@ -293,7 +305,7 @@ extension CSV {
 
     /// Unavailable.
     @available(*, unavailable, message: "Use init(stream:config:) instead")
-    public init(
+    public convenience init(
         stream: InputStream,
         hasHeaderRow: Bool = defaultHasHeaderRow,
         trimFields: Bool = defaultTrimFields,
@@ -309,7 +321,7 @@ extension CSV {
 
     /// Unavailable.
     @available(*, unavailable, message: "Use init(string:config:) instead")
-    public init(
+    public convenience init(
         string: String,
         hasHeaderRow: Bool = defaultHasHeaderRow,
         trimFields: Bool = defaultTrimFields,

Sources/CSVError.swift

@@ -16,6 +16,8 @@ public enum CSVError: Error {
     /// No overview available.
     case streamErrorHasOccurred(error: Error)
     /// No overview available.
+    case unicodeDecoding
+    /// No overview available.
     case cannotReadHeaderRow
     /// No overview available.
     case stringEncodingMismatch

Sources/UnicodeIterator.swift

@@ -6,7 +6,7 @@
 //  Copyright © 2016 yaslab. All rights reserved.
 //
 
-internal struct UnicodeIterator<
+internal class UnicodeIterator<
     Input: IteratorProtocol,
     InputEncoding: UnicodeCodec>
     : IteratorProtocol
@@ -14,17 +14,22 @@ internal struct UnicodeIterator<
 
     private var input: Input
     private var inputEncoding: InputEncoding
+    internal var errorHandler: ((Error) -> Void)? = nil
 
     internal init(input: Input, inputEncodingType: InputEncoding.Type) {
         self.input = input
         self.inputEncoding = inputEncodingType.init()
     }
 
-    internal mutating func next() -> UnicodeScalar? {
+    internal func next() -> UnicodeScalar? {
         switch inputEncoding.decode(&input) {
-        case .scalarValue(let c): return c
+        case .scalarValue(let c):
-        case .emptyInput: return nil
+            return c
-        case .error: return nil
+        case .emptyInput:
+            return nil
+        case .error:
+            errorHandler?(CSVError.unicodeDecoding)
+            return nil
         }
     }