Small fixes. (#11)

- Eliminates warnings in the generated code by using special handling for methods that would result in a `Void` return.
- Fix crash when address does respond to a certain function (e.g. if address is not a HumanStandardToken decoding the`0x` return data for `Name` function would crash).
- Revert back to official CryptoSwift.
- Improve testing guide.
- Add `unwrap()` to some types to allow for getting the wrapped value out of the solidity wrapper.

.gitignore

@@ -70,3 +70,8 @@ fastlane/test_output
 # Xcodeproj generated with `swift package generate-xcodeproj`.
 # Can be safely ignored and recreated, as it's only used for development. 
 Bivrost.xcodeproj
+
+# Local test data should not be committed.
+testcontracts
+testoutput
+

.swiftlint.yml

@@ -39,4 +39,4 @@ opt_in_rules: # some rules are only opt-in
 # Make certain rules give out an error
 force_cast: error
 force_try: error
-force_unwrapping: error
+force_unwrapping: warning

Package.resolved

@@ -21,11 +21,11 @@
       },
       {
         "package": "CryptoSwift",
-        "repositoryURL": "https://github.com/zweigraf/CryptoSwift.git",
+        "repositoryURL": "https://github.com/krzyzanowskim/CryptoSwift",
         "state": {
           "branch": null,
-          "revision": "fdd115318528c9c25a06c0a89553f71bde7233da",
-          "version": null
+          "revision": "d0084e4a6fe9490b3baab3d3c2aad58d3a852daf",
+          "version": "0.8.0"
         }
       },
       {
@@ -51,8 +51,8 @@
         "repositoryURL": "https://github.com/Quick/Quick.git",
         "state": {
           "branch": null,
-          "revision": "c498edf4aabb694a5b8a861ec3d69f0c5ab57d9e",
-          "version": null
+          "revision": "0ff81f2c665b4381f526bd656f8708dd52a9ea2f",
+          "version": "1.2.0"
         }
       },
       {

Package.swift

@@ -11,8 +11,8 @@ let package = Package(
     dependencies: [
         .package(url: "https://github.com/krzyzanowskim/CryptoSwift", .upToNextMinor(from: "0.8.0")),
         .package(url: "https://github.com/attaswift/BigInt.git", .upToNextMajor(from: "3.0.0")),
-        .package(url: "https://github.com/Quick/Nimble.git", .upToNextMajor(from: "7.0.2")),
-        .package(url: "https://github.com/Quick/Quick.git", .revision("c498edf4aabb694a5b8a861ec3d69f0c5ab57d9e")),
+        .package(url: "https://github.com/Quick/Nimble.git", .upToNextMinor(from: "7.0.2")),
+        .package(url: "https://github.com/Quick/Quick.git", .upToNextMinor(from: "1.2.0")),
         .package(url: "https://github.com/kylef/Commander.git", .revision("e0cbee1bd73778c1076c675eaf660e97d09f3b32")),
         // PathKit fork supporting SPM4
         .package(url: "https://github.com/PoissonBallon/PathKit.git", .branch("master")),

README.md

@@ -2,8 +2,6 @@
 
 🔥 🌈 Bridge between Solidity Contracts and Swift
 
-[![CI Status](http://img.shields.io/travis/gnosis/bivrost-swift.svg?style=flat)](https://travis-ci.org/gnosis/bivrost-swift)
-
 Bivrost is in very early development. Do not use this for anything important.
 
 ## Description
@@ -116,4 +114,8 @@ Bivrost is available under the MIT license. See the LICENSE file for more info.
 
 ## Issues
 
-Tests currently do not work when generating an Xcode project via `swift package generate-xcodeproj`. This issue is described at the bottom of <https://github.com/Quick/Quick/issues/707>. Drop to the CMD and use `swift test` for testing.
+Tests currently do not work when generating an Xcode project via `swift package generate-xcodeproj`. This issue is described in <https://github.com/Quick/Quick/issues/751>. 
+
+Workarounds:
+- Drop to the CMD and use `swift test` for testing.
+- Go to the `QuickSpecBase` target build settings in the generated Xcode project. Set `Enables Module` to `YES` (`CLANG_ENABLE_MODULES=YES`). Now testing should work.

Resources/BivrostError.swift

@@ -12,6 +12,8 @@ import Foundation
 
 enum BivrostError: Error {
     enum Decoder: Error {
+        case endOfSourceData
+
         // Decoding
         case invalidBool(hex: String)
         case invalidUInt(hex: String)

Resources/Coding/BaseDecoder.swift

@@ -59,14 +59,14 @@ struct BaseDecoder {
     }
 
     static func decodeBytes(source: PartitionData) throws -> Data {
-        let sizePart = source.consume()
+        let sizePart = try source.consume()
         guard let size = Int(sizePart, radix: 16) else {
             throw BivrostError.Decoder.invalidBytesLength(hex: sizePart)
         }
 
         var byteHolder = Data()
         while byteHolder.count < size {
-            if let data = Data(fromHexEncodedString: source.consume()) {
+            if let data = Data(fromHexEncodedString: try source.consume()) {
                 byteHolder.append(data)
             }
         }
@@ -107,7 +107,7 @@ struct BaseDecoder {
         }
         // We have dynamic types, we need to check the dynamic array
         // Consume all locations to jump cursor ahead to dynamic section
-        (0..<capacity).forEach { _ in _ = source.consume() }
+        try (0..<capacity).forEach { _ in _ = try source.consume() }
         return try (0..<capacity).map { _ in try decoder(source) }
     }
 }
@@ -126,7 +126,10 @@ extension BaseDecoder {
 
         var index: Int = 0
 
-        func consume() -> String {
+        func consume() throws -> String {
+            guard index < lines.count else {
+                throw BivrostError.Decoder.endOfSourceData
+            }
             let returnValue = lines[index]
             index += 1
             return returnValue

Resources/Extensions/StringExtension.swift

@@ -84,3 +84,13 @@ extension String {
         return forBytes * 2
     }
 }
+
+// MARK: - Hex Helper
+extension String {
+    /// Returns a new string, removing a '0x' prefix if present.
+    var withoutHexPrefix: String {
+        return hasPrefix("0x")
+            ? String(dropFirst(2))
+            : self
+    }
+}

Resources/Types/Address.swift

@@ -15,9 +15,7 @@ public extension Solidity {
         private let bigInt: BigUInt
 
         init(_ address: Swift.String) throws {
-            let hex = address.hasPrefix("0x")
-                ? Swift.String(address[address.index(address.startIndex, offsetBy: 2)...])
-                : address
+            let hex = address.withoutHexPrefix
             guard let bigInt = BigUInt(hex, radix: 16) else {
                 throw BivrostError.Address.invalidAddress(hex)
             }

Resources/Types/ArrayX.swift

@@ -10,7 +10,7 @@
 extension _DoNotUse {
     // swiftlint:disable:next type_name
     class _ArrayX<T: SolidityCodable & Equatable> {
-        private let items: [T]
+        let items: [T]
         class var length: UInt {
             fatalError("Not meant to be called directly.")
         }

Resources/Types/Bool.swift

@@ -10,14 +10,20 @@ import BigInt
 
 public extension Solidity {
     struct Bool {
+        private let value: Swift.Bool
         private let wrapper: UInt8
 
         init(_ value: Swift.Bool) {
+            self.value = value
             guard let wrapper = try? UInt8(BigUInt(value ? 1 : 0)) else {
                 fatalError("Solidity.Bool could not be created with value of \(value). This should not happen.")
             }
             self.wrapper = wrapper
         }
+
+        func unwrap() -> Swift.Bool {
+            return value
+        }
     }
 }
 

Resources/Types/Bytes.swift

@@ -21,6 +21,10 @@ public extension Solidity {
             self.value = value
             self.length = length
         }
+
+        func unwrap() -> Data {
+            return value
+        }
     }
 }
 

Resources/Types/BytesX.swift

@@ -24,6 +24,10 @@ public extension _DoNotUse {
             }
             self.value = value
         }
+
+        func unwrap() -> Data {
+            return value
+        }
     }
 }
 

Resources/Types/Function.swift

@@ -41,7 +41,7 @@ extension Solidity.Function: StaticType {
     }
 
     static func decode(source: BaseDecoder.PartitionData) throws -> Solidity.Function {
-        let line = source.consume()
+        let line = try source.consume()
         // 20 bytes / 40 chars for Address as UInt160
         let addressHex = String(line[line.startIndex ..< line.index(startDistance: 40)])
         let uint = try BaseDecoder.decodeUInt(data: addressHex)

Resources/Types/IntX.swift

@@ -26,6 +26,10 @@ public extension _DoNotUse {
             }
             value = int
         }
+
+        func unwrap() -> BigInt {
+            return value
+        }
     }
 }
 

Resources/Types/String.swift

@@ -9,14 +9,21 @@
 public extension Solidity {
     struct String {
         let wrapper: Solidity.Bytes
+        let value: Swift.String
 
         init?(_ value: Swift.String) {
+            self.value = value
+
             guard let data = value.data(using: .utf8),
                 let bytes = Solidity.Bytes(data) else {
                 return nil
             }
             self.wrapper = bytes
         }
+
+        func unwrap() -> Swift.String {
+            return value
+        }
     }
 }
 

Resources/Types/UIntX.swift

@@ -26,6 +26,10 @@ public extension _DoNotUse {
             }
             value = uint
         }
+
+        func unwrap() -> BigUInt {
+            return value
+        }
     }
 }
 

Resources/Types/VariableArray.swift

@@ -26,7 +26,7 @@ extension Solidity {
 // MARK: - DynamicType
 extension Solidity.VariableArray: DynamicType {
     static func decode(source: BaseDecoder.PartitionData) throws -> Solidity.VariableArray<T> {
-        let sizePart = source.consume()
+        let sizePart = try source.consume()
         guard let size = UInt(sizePart, radix: 16) else {
             throw BivrostError.Decoder.invalidArrayLength(hex: sizePart)
         }

Sources/BivrostKit/Generating/ContractTemplateModel.swift

@@ -20,9 +20,11 @@ struct ContractTemplateModel {
 
         let decodeReturnReturnValue: String // Name to be returned at the end of decode(returnData:)
         let decodeReturnTypes: [DecodeType]
+        let hasEmptyDecodeReturnFunction: Bool
 
         let decodeArgumentsReturnValue: String // Name to be returned at the end of decode(argumentsData:)
         let decodeArgumentsTypes: [DecodeType]
+        let hasEmptyDecodeArgumentsFunction: Bool
 
         struct DecodeType {
             let name: String
@@ -61,12 +63,16 @@ struct ContractTemplateModel {
                 let outputString = tupleString(for: object.outputs)
 
                 let encodeArgumentsString = encodeArguments(for: object.inputs)
+
                 let decodeReturnTypesArray = decodeTypes(for: object.outputs)
+                let hasEmptyDecodeReturnFunction = decodeReturnTypesArray.isEmpty
                 let decodeReturnReturnValueString = decodeReturnReturnValue(for: decodeReturnTypesArray)
+
                 let decodeArgumentsTypesArray = decodeTypes(for: object.inputs)
+                let hasEmptyDecodeArgumentsFunction = decodeArgumentsTypesArray.isEmpty
                 let decodeArgumentsReturnValueString = decodeArgumentsReturnValue(for: decodeArgumentsTypesArray)
 
-                return ContractTemplateModel.Function(name: preparedFunctionName, methodId: functionMethodId, input: inputString, output: outputString, encodeArguments: encodeArgumentsString, decodeReturnReturnValue: decodeReturnReturnValueString, decodeReturnTypes: decodeReturnTypesArray, decodeArgumentsReturnValue: decodeArgumentsReturnValueString, decodeArgumentsTypes: decodeArgumentsTypesArray)
+                return ContractTemplateModel.Function(name: preparedFunctionName, methodId: functionMethodId, input: inputString, output: outputString, encodeArguments: encodeArgumentsString, decodeReturnReturnValue: decodeReturnReturnValueString, decodeReturnTypes: decodeReturnTypesArray, hasEmptyDecodeReturnFunction: hasEmptyDecodeReturnFunction, decodeArgumentsReturnValue: decodeArgumentsReturnValueString, decodeArgumentsTypes: decodeArgumentsTypesArray, hasEmptyDecodeArgumentsFunction: hasEmptyDecodeArgumentsFunction)
         }
     }
 }

Sources/BivrostKit/Generating/Templates/ContractTemplate.swift

@@ -17,54 +17,63 @@ extension Templates {
 
         struct {{ contract.name }} {
             {% for function in contract.functions %}
+
             struct {{ function.name }}: SolidityFunction {
                 static let methodId = "{{ function.methodId }}"
                 typealias Return = {{ function.output }}
                 typealias Arguments = {{ function.input }}
-                
+
                 static func encodeCall(arguments: Arguments) -> String {
                     return "0x\\(methodId)\\(BaseEncoder.encode(arguments: {{ function.encodeArguments }}))"
                 }
-                
+
+                {% if function.hasEmptyDecodeReturnFunction %}
+                static func decode(returnData: String) throws -> Return {}
+                {% else %}
                 static func decode(returnData: String) throws -> Return {
                     let source = BaseDecoder.partition(returnData)
-                    // Static Types & Location
+                    // Decode Static Types & Locations for Dynamic Types
                     {% for decodedType in function.decodeReturnTypes %}
                         {% if decodedType.isDynamic %}
-                    // Ignore location for dynamic type
-                    _ = source.consume()
+                    // Ignore location for {{ decodedType.name }} (dynamic type)
+                    _ = try source.consume()
                         {% else %}
                     let {{ decodedType.name }} = try {{ decodedType.type }}.decode(source: source)
                         {% endif %}
                     {% endfor %}
-                    // Dynamic Types
+                    // Dynamic Types (if any)
                     {% for decodedType in function.decodeReturnTypes %}
                         {% if decodedType.isDynamic %}
                     let {{ decodedType.name }} = try {{ decodedType.type }}.decode(source: source)
                         {% endif %}
                     {% endfor %}
                     return {{ function.decodeReturnReturnValue }}
                 }
-                
+                {% endif %}
+
+                {% if function.hasEmptyDecodeArgumentsFunction %}
+                static func decode(argumentsData: String) throws -> Arguments {}
+                {% else %}
                 static func decode(argumentsData: String) throws -> Arguments {
                     let source = BaseDecoder.partition(argumentsData)
-                    // Static Types & Location
+                    // Decode Static Types & Locations for Dynamic Types
                     {% for decodedType in function.decodeArgumentsTypes %}
                         {% if decodedType.isDynamic %}
-                    // Ignore location for dynamic type
-                    _ = source.consume()
+                    // Ignore location for {{ decodedType.name }} (dynamic type)
+                    _ = try source.consume()
                         {% else %}
                     let {{ decodedType.name }} = try {{ decodedType.type }}.decode(source: source)
                         {% endif %}
                     {% endfor %}
-                    // Dynamic Types
+                    // Dynamic Types (if any)
                     {% for decodedType in function.decodeArgumentsTypes %}
                         {% if decodedType.isDynamic %}
                     let {{ decodedType.name }} = try {{ decodedType.type }}.decode(source: source)
                         {% endif %}
                     {% endfor %}
                     return {{ function.decodeArgumentsReturnValue }}
                 }
+                {% endif %}
             }
             {% endfor %}
         }

Sources/BivrostKit/Parsing/ContractParser.swift

@@ -21,7 +21,7 @@ struct ContractParser {
     /// - Throws: Throws if the json was malformed, e.g. a required field was missing.
     static func parseContract(from json: [String: Any]) throws -> Contract {
         guard let name = json[.contractName] as? String else {
-            throw ParsingError.contractNameInvalid
+            throw ParsingError.contractNameInvalid(json: json)
         }
         guard let elementsJson = json[.abi] as? [[String: Any]] else {
             throw ParsingError.contractAbiInvalid

Sources/BivrostKit/Parsing/ParsingError.swift

@@ -19,6 +19,6 @@ enum ParsingError: Error {
     case eventInputInvalid
     case parameterTypeInvalid
     case parameterTypeNotFound
-    case contractNameInvalid
+    case contractNameInvalid(json: [String: Any])
     case contractAbiInvalid
 }