feat: Added error comparing (#250)

* Added error comparing

Add the ability to easily compare Swift Errors with ParseErrors.

* Added tests

* Fix SwiftLint script for autocorrection

* Changelog

* Recommendations from cbaker6

* Recommendations from cbaker6

* Description change

* lint

* Requested changes

* Requested changes

* nits on comments and structure

Co-authored-by: Corey <[email protected]>

Author: vdkdamian

CHANGELOG.md

@@ -4,6 +4,9 @@
 [Full Changelog](https://github.com/parse-community/Parse-Swift/compare/1.10.1...main)
 * _Contributing to this repo? Add info about your change here to be included in the next release_
 
+__Improvements__
+- Added an extension to compare a Swift Error with a single ParseError or multiple ParseErrors ([#250](https://github.com/parse-community/Parse-Swift/pull/250)), thanks to [Damian Van de Kauter](https://github.com/novemTeam).
+
 ### 1.10.1
 [Full Changelog](https://github.com/parse-community/Parse-Swift/compare/1.10.0...1.10.1)
 

ParseSwift.playground/Pages/2 - Finding Objects.xcplaygroundpage/Contents.swift

@@ -54,7 +54,11 @@ query.limit(2).find(callbackQueue: .main) { results in
         }
 
     case .failure(let error):
-        assertionFailure("Error querying: \(error)")
+        if error.equalsTo(.objectNotFound) {
+            assertionFailure("Object not found for this query")
+        } else {
+            assertionFailure("Error querying: \(error)")
+        }
     }
 }
 
@@ -80,7 +84,11 @@ query.first { results in
         print("Found score: \(score)")
 
     case .failure(let error):
-        assertionFailure("Error querying: \(error)")
+        if error.containedIn([.objectNotFound, .invalidQuery]) {
+            assertionFailure("The query is invalid or the object is not found.")
+        } else {
+            assertionFailure("Error querying: \(error)")
+        }
     }
 }
 
@@ -109,7 +117,11 @@ querySelect.first { results in
         print("Found score using select: \(score)")
 
     case .failure(let error):
-        assertionFailure("Error querying: \(error)")
+        if let parseError = error.equalsTo(.objectNotFound) {
+            assertionFailure("Object not found: \(parseError)")
+        } else {
+            assertionFailure("Error querying: \(error)")
+        }
     }
 }
 
@@ -124,7 +136,11 @@ queryExclude.first { results in
         print("Found score using exclude: \(score)")
 
     case .failure(let error):
-        assertionFailure("Error querying: \(error)")
+        if let parseError = error.containedIn(.objectNotFound, .invalidQuery) {
+            assertionFailure("Matching error found: \(parseError)")
+        } else {
+            assertionFailure("Error querying: \(error)")
+        }
     }
 }
 

ParseSwift.xcodeproj/project.pbxproj

@@ -1723,7 +1723,7 @@
 			);
 			runOnlyForDeploymentPostprocessing = 0;
 			shellPath = /bin/sh;
-			shellScript = "if which swiftlint >/dev/null; then\n    swiftlint autocorrect && swiftlint --strict\nelse\n    echo \"warning: SwiftLint not installed, download from https://github.com/realm/SwiftLint\"\nfi\n";
+			shellScript = "if which swiftlint >/dev/null; then\n    swiftlint --fix --strict\nelse\n    echo \"warning: SwiftLint not installed, download from https://github.com/realm/SwiftLint\"\nfi\n";
 		};
 		918CED61268A23A700CFDC83 /* SwiftLint */ = {
 			isa = PBXShellScriptBuildPhase;

Sources/ParseSwift/Types/ParseError.swift

@@ -406,3 +406,123 @@ extension ParseError: CustomStringConvertible {
         debugDescription
     }
 }
+
+// MARK: Compare Errors
+public extension Error {
+
+    /**
+     Returns the respective `ParseError` if the given `ParseError` code is equal to the error.
+     
+    **Example use case:**
+    ~~~
+    if let parseError = error.equalsTo(.objectNotFound)  {
+        print(parseError.description)
+    }
+    ~~~
+     - parameter errorCode: A `ParseError` code to compare to.
+     
+     - returns: Returns the `ParseError` with respect to the `Error`. If the error is not a `ParseError`, returns nil.
+     */
+    func equalsTo(_ errorCode: ParseError.Code) -> ParseError? {
+        guard let error = self as? ParseError,
+                error.code == errorCode else {
+            return nil
+        }
+        return error
+    }
+
+    /**
+     Validates if the given `ParseError` code is equal to the error.
+     
+    **Example use case:**
+    ~~~
+    if error.equalsTo(.objectNotFound)  {
+        //Do stuff
+    }
+    ~~~
+     - parameter errorCode: A `ParseError` code to compare to.
+     
+     - returns: A boolean indicating whether or not the `Error` is the `errorCode`.
+     */
+    func equalsTo(_ errorCode: ParseError.Code) -> Bool {
+        guard equalsTo(errorCode) != nil else {
+            return false
+        }
+        return true
+    }
+
+    /**
+     Returns the respective `ParseError` if the `Error` is contained in the array of `ParseError` codes.
+     
+    **Example use case:**
+    ~~~
+    if let parseError = error.containedIn([.objectNotFound, .invalidQuery])  {
+        print(parseError.description)
+    }
+    ~~~
+     - parameter errorCodes: An array of zero or more of `ParseError` codes to compare to.
+     
+     - returns: Returns the `ParseError` with respect to the `Error`. If the error is not a `ParseError`, returns nil.
+     */
+    func containedIn(_ errorCodes: [ParseError.Code]) -> ParseError? {
+        guard let error = self as? ParseError,
+              errorCodes.contains(error.code) == true else {
+            return nil
+        }
+        return error
+    }
+
+    /**
+     Returns the respective `ParseError` if the `Error` is contained in the list of `ParseError` codes.
+     
+    **Example use case:**
+    ~~~
+    if let parseError = error.containedIn(.objectNotFound, .invalidQuery)  {
+        print(parseError.description)
+    }
+    ~~~
+     - parameter errorCodes: A variadic amount of zero or more of `ParseError` codes to compare to.
+     
+     - returns: Returns the `ParseError` with respect to the `Error`. If the error is not a `ParseError`, returns nil.
+     */
+    func containedIn(_ errorCodes: ParseError.Code...) -> ParseError? {
+        containedIn(errorCodes)
+    }
+
+    /**
+     Validates if the given `ParseError` codes contains the error.
+     
+    **Example use case:**
+    ~~~
+    if error.containedIn([.objectNotFound, .invalidQuery])  {
+        //Do stuff
+    }
+    ~~~
+     - parameter errorCodes: An array of zero or more of `ParseError` codes to compare to.
+     
+     - returns: A boolean indicating whether or not the `Error` is contained in the `errorCodes`.
+     */
+    func containedIn(_ errorCodes: [ParseError.Code]) -> Bool {
+        guard containedIn(errorCodes) != nil else {
+            return false
+        }
+        return true
+    }
+
+    /**
+     Validates if the given `ParseError` codes contains the error.
+     
+    **Example use case:**
+    ~~~
+    if error.containedIn(.objectNotFound, .invalidQuery)  {
+        //Do stuff
+    }
+    ~~~
+     - parameter errorCodes: A variadic amount of zero or more of `ParseError` codes to compare to.
+     
+     - returns: A boolean indicating whether or not the `Error` is contained in the `errorCodes`.
+     */
+    func containedIn(_ errorCodes: ParseError.Code...) -> Bool {
+        containedIn(errorCodes)
+    }
+}

Tests/ParseSwiftTests/ParseErrorTests.swift

@@ -62,4 +62,34 @@ class ParseErrorTests: XCTestCase {
                        "ParseError code=\(ParseError.Code.other.rawValue) error=\(message) otherCode=\(code)")
         XCTAssertEqual(decoded.otherCode, code)
     }
+
+    func testCompare() throws {
+        let code = ParseError.Code.objectNotFound.rawValue
+        let message = "testing ParseError"
+        guard let encoded = "{\"error\":\"\(message)\",\"code\":\(code)}".data(using: .utf8) else {
+            XCTFail("Should have unwrapped")
+            return
+        }
+        let decoded = try ParseCoding.jsonDecoder().decode(ParseError.self, from: encoded)
+
+        let error: Error = decoded
+
+        XCTAssertTrue(error.equalsTo(.objectNotFound))
+        XCTAssertFalse(error.equalsTo(.invalidQuery))
+
+        XCTAssertTrue(error.containedIn(.objectNotFound, .invalidQuery))
+        XCTAssertFalse(error.containedIn(.operationForbidden, .invalidQuery))
+
+        XCTAssertTrue(error.containedIn([.objectNotFound, .invalidQuery]))
+        XCTAssertFalse(error.containedIn([.operationForbidden, .invalidQuery]))
+
+        XCTAssertNotNil(error.equalsTo(.objectNotFound))
+        XCTAssertNil(error.equalsTo(.invalidQuery))
+
+        XCTAssertNotNil(error.containedIn(.objectNotFound, .invalidQuery))
+        XCTAssertNil(error.containedIn(.operationForbidden, .invalidQuery))
+
+        XCTAssertNotNil(error.containedIn([.objectNotFound, .invalidQuery]))
+        XCTAssertNil(error.containedIn([.operationForbidden, .invalidQuery]))
+    }
 }