Open up Target protocols

SnapKit.xcodeproj/project.pbxproj

@@ -11,6 +11,7 @@
 		3CA7D6C224592D4D005E10C2 /* ConstraintMakerRelatable+Extensions.swift in Sources */ = {isa = PBXBuildFile; fileRef = 3CA7D6C124592D4D005E10C2 /* ConstraintMakerRelatable+Extensions.swift */; };
 		7E1CB2AE227BB5520066B6C0 /* ConstraintDirectionalInsetTarget.swift in Sources */ = {isa = PBXBuildFile; fileRef = 7E1CB2AD227BB5520066B6C0 /* ConstraintDirectionalInsetTarget.swift */; };
 		7E1CB2B0227BBDF70066B6C0 /* ConstraintDirectionalInsets.swift in Sources */ = {isa = PBXBuildFile; fileRef = 7E1CB2AF227BBDF70066B6C0 /* ConstraintDirectionalInsets.swift */; };
+		37AC176121B76CE700974541 /* RawRepresentable+Extensions.swift in Sources */ = {isa = PBXBuildFile; fileRef = 37AC176021B76CE700974541 /* RawRepresentable+Extensions.swift */; };
 		EE235F5F1C5785BC00C08960 /* Debugging.swift in Sources */ = {isa = PBXBuildFile; fileRef = EE235F5E1C5785BC00C08960 /* Debugging.swift */; };
 		EE235F6D1C5785C600C08960 /* Constraint.swift in Sources */ = {isa = PBXBuildFile; fileRef = EE235F621C5785C600C08960 /* Constraint.swift */; };
 		EE235F701C5785C600C08960 /* ConstraintDescription.swift in Sources */ = {isa = PBXBuildFile; fileRef = EE235F631C5785C600C08960 /* ConstraintDescription.swift */; };
@@ -51,6 +52,7 @@
 /* Begin PBXFileReference section */
 		2DBA080D1F1FAD66001CFED4 /* Typealiases.swift */ = {isa = PBXFileReference; lastKnownFileType = sourcecode.swift; path = Typealiases.swift; sourceTree = "<group>"; };
 		3CA7D6C124592D4D005E10C2 /* ConstraintMakerRelatable+Extensions.swift */ = {isa = PBXFileReference; lastKnownFileType = sourcecode.swift; path = "ConstraintMakerRelatable+Extensions.swift"; sourceTree = "<group>"; };
+		37AC176021B76CE700974541 /* RawRepresentable+Extensions.swift */ = {isa = PBXFileReference; lastKnownFileType = sourcecode.swift; path = "RawRepresentable+Extensions.swift"; sourceTree = "<group>"; };
 		537DCE9A1C35CD4100B5B899 /* UIKit.framework */ = {isa = PBXFileReference; lastKnownFileType = wrapper.framework; name = UIKit.framework; path = Platforms/AppleTVOS.platform/Developer/SDKs/AppleTVOS9.1.sdk/System/Library/Frameworks/UIKit.framework; sourceTree = DEVELOPER_DIR; };
 		7E1CB2AD227BB5520066B6C0 /* ConstraintDirectionalInsetTarget.swift */ = {isa = PBXFileReference; lastKnownFileType = sourcecode.swift; path = ConstraintDirectionalInsetTarget.swift; sourceTree = "<group>"; };
 		7E1CB2AF227BBDF70066B6C0 /* ConstraintDirectionalInsets.swift */ = {isa = PBXFileReference; lastKnownFileType = sourcecode.swift; path = ConstraintDirectionalInsets.swift; sourceTree = "<group>"; };
@@ -139,6 +141,7 @@
 			children = (
 				EE235FC61C5785E200C08960 /* ConstraintView+Extensions.swift */,
 				EEF68FAF1D784FB100980C26 /* ConstraintLayoutGuide+Extensions.swift */,
+				37AC176021B76CE700974541 /* RawRepresentable+Extensions.swift */,
 				EEF68FB31D784FBA00980C26 /* UILayoutSupport+Extensions.swift */,
 				3CA7D6C124592D4D005E10C2 /* ConstraintMakerRelatable+Extensions.swift */,
 			);
@@ -384,6 +387,7 @@
 				EE235F881C5785C600C08960 /* ConstraintItem.swift in Sources */,
 				2DBA080E1F1FAD66001CFED4 /* Typealiases.swift in Sources */,
 				EE235F9A1C5785CE00C08960 /* ConstraintPriorityTarget.swift in Sources */,
+				37AC176121B76CE700974541 /* RawRepresentable+Extensions.swift in Sources */,
 				EEF68FC01D7865AA00980C26 /* ConstraintLayoutSupport.swift in Sources */,
 				EEF68FB01D784FB100980C26 /* ConstraintLayoutGuide+Extensions.swift in Sources */,
 				EE235F761C5785C600C08960 /* ConstraintConfig.swift in Sources */,

Sources/ConstraintConstantTarget.swift

@@ -29,6 +29,9 @@
 
 
 public protocol ConstraintConstantTarget {
+
+    func constraintConstantTargetValueFor(layoutAttribute: LayoutAttribute) -> CGFloat
+
 }
 
 extension CGPoint: ConstraintConstantTarget {
@@ -48,7 +51,7 @@ extension ConstraintDirectionalInsets: ConstraintConstantTarget {
 
 extension ConstraintConstantTarget {
 
-    internal func constraintConstantTargetValueFor(layoutAttribute: LayoutAttribute) -> CGFloat {
+    public func constraintConstantTargetValueFor(layoutAttribute: LayoutAttribute) -> CGFloat {
         if let value = self as? CGFloat {
             return value
         }

Sources/ConstraintInsetTarget.swift

@@ -29,6 +29,9 @@
 
 
 public protocol ConstraintInsetTarget: ConstraintConstantTarget {
+
+    var constraintInsetTargetValue: ConstraintInsets { get }
+
 }
 
 extension Int: ConstraintInsetTarget {
@@ -51,7 +54,7 @@ extension ConstraintInsets: ConstraintInsetTarget {
 
 extension ConstraintInsetTarget {
 
-    internal var constraintInsetTargetValue: ConstraintInsets {
+    public var constraintInsetTargetValue: ConstraintInsets {
         if let amount = self as? ConstraintInsets {
             return amount
         } else if let amount = self as? Float {

Sources/ConstraintOffsetTarget.swift

@@ -29,6 +29,9 @@
 
 
 public protocol ConstraintOffsetTarget: ConstraintConstantTarget {
+
+    var constraintOffsetTargetValue: CGFloat { get }
+
 }
 
 extension Int: ConstraintOffsetTarget {
@@ -48,7 +51,7 @@ extension CGFloat: ConstraintOffsetTarget {
 
 extension ConstraintOffsetTarget {
 
-    internal var constraintOffsetTargetValue: CGFloat {
+    public var constraintOffsetTargetValue: CGFloat {
         let offset: CGFloat
         if let amount = self as? Float {
             offset = CGFloat(amount)

Sources/RawRepresentable+Extensions.swift

@@ -0,0 +1,61 @@
+//
+//  SnapKit
+//
+//  Copyright (c) 2011-Present SnapKit Team - https://github.com/SnapKit
+//
+//  Permission is hereby granted, free of charge, to any person obtaining a copy
+//  of this software and associated documentation files (the "Software"), to deal
+//  in the Software without restriction, including without limitation the rights
+//  to use, copy, modify, merge, publish, distribute, sublicense, and/or sell
+//  copies of the Software, and to permit persons to whom the Software is
+//  furnished to do so, subject to the following conditions:
+//
+//  The above copyright notice and this permission notice shall be included in
+//  all copies or substantial portions of the Software.
+//
+//  THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
+//  IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
+//  FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE
+//  AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
+//  LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
+//  OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN
+//  THE SOFTWARE.
+
+#if os(iOS) || os(tvOS)
+    import UIKit
+#else
+    import AppKit
+#endif
+
+
+public extension RawRepresentable where Self: ConstraintConstantTarget, Self.RawValue: ConstraintConstantTarget {
+
+    public func constraintConstantTargetValueFor(layoutAttribute: LayoutAttribute) -> CGFloat {
+        return rawValue.constraintConstantTargetValueFor(layoutAttribute: layoutAttribute)
+    }
+
+}
+
+public extension RawRepresentable where Self: ConstraintMultiplierTarget, Self.RawValue: ConstraintMultiplierTarget {
+
+    public var constraintMultiplierTargetValue: CGFloat {
+        return rawValue.constraintMultiplierTargetValue
+    }
+
+}
+
+public extension RawRepresentable where Self: ConstraintOffsetTarget, Self.RawValue: ConstraintOffsetTarget {
+
+    public var constraintOffsetTargetValue: CGFloat {
+        return rawValue.constraintOffsetTargetValue
+    }
+
+}
+
+public extension RawRepresentable where Self: ConstraintInsetTarget, Self.RawValue: ConstraintInsetTarget {
+
+    public var constraintInsetTargetValue: ConstraintInsets {
+        return rawValue.constraintInsetTargetValue
+    }
+
+}

Sources/Typealiases.swift

@@ -27,16 +27,16 @@ import Foundation
     import UIKit
 #if swift(>=4.2)
     typealias LayoutRelation = NSLayoutConstraint.Relation
-    typealias LayoutAttribute = NSLayoutConstraint.Attribute
+    public typealias LayoutAttribute = NSLayoutConstraint.Attribute
 #else
     typealias LayoutRelation = NSLayoutRelation
-    typealias LayoutAttribute = NSLayoutAttribute
+    public typealias LayoutAttribute = NSLayoutAttribute
 #endif
     typealias LayoutPriority = UILayoutPriority
 #else
     import AppKit
     typealias LayoutRelation = NSLayoutConstraint.Relation
-    typealias LayoutAttribute = NSLayoutConstraint.Attribute
+    public typealias LayoutAttribute = NSLayoutConstraint.Attribute
     typealias LayoutPriority = NSLayoutConstraint.Priority
 #endif
 

Tests/SnapKitTests/Tests.swift

@@ -768,4 +768,29 @@ class SnapKitTests: XCTestCase {
         let higherPriority: ConstraintPriority = ConstraintPriority.high.advanced(by: 1)
         XCTAssertEqual(higherPriority.value, highPriority.value + 1)
     }
+
+    func testEnumAsConstraints() {
+        let view = View()
+        self.container.addSubview(view)
+
+        view.snp.makeConstraints { make in
+            make.top.equalTo(Enum.value)
+            make.height.equalToSuperview().multipliedBy(Enum.value)
+            make.left.equalToSuperview().offset(Enum.value)
+            make.right.equalToSuperview().inset(Enum.value)
+        }
+
+        XCTAssertEqual(self.container.snp_constraints.count, 4, "Should have 4 constraints")
+
+        let constraints = (self.container.snp_constraints as! [NSLayoutConstraint]).sorted { $0.constant > $1.constant }
+
+        XCTAssertEqual(constraints[0].constant, Enum.value.rawValue, "Should be enum")
+        XCTAssertEqual(constraints[1].constant, Enum.value.rawValue, "Should be enum")
+        XCTAssertEqual(constraints[2].multiplier, Enum.value.rawValue, "Multiplier should be enum")
+        XCTAssertEqual(constraints[3].constant, -Enum.value.rawValue, "Should be negative enum")
+    }
+}
+
+private enum Enum: CGFloat, ConstraintRelatableTarget, ConstraintMultiplierTarget, ConstraintOffsetTarget, ConstraintInsetTarget {
+    case value = 50
 }