move codingPath into a parent protocol and use it more widely between…

… validation and other OpenAPI errors. see if duplicate validation errors are due to an extra pass at the document that is no longer necessary for some reason (fix in Codable, perhaps).

Sources/OpenAPIKit/Validator/Validation.swift

@@ -109,7 +109,7 @@ public struct Validation<Subject: Validatable> {
 
 /// Validation errors are just a textual reason for validation failure and
 /// a coding path where the validation error occurred.
-public struct ValidationError: Swift.Error, CustomStringConvertible {
+public struct ValidationError: Swift.Error, CustomStringConvertible, PathContextError {
     /// The reason for the validation failure.
     public let reason: String
     /// The location where the failure occurred.
@@ -149,6 +149,7 @@ public struct ValidationErrorCollection: Swift.Error, CustomStringConvertible, E
     public var description: String { localizedDescription }
 
     public var swiftErrors: [Swift.Error] { values }
+    public var pathContextErrors: [PathContextError] { values }
 }
 
 /// Erases the type on which a `Validator` is specialized and combines

Sources/OpenAPIKit/Validator/Validator.swift

@@ -36,7 +36,7 @@ extension OpenAPI.Document {
         // and then encoding with the single value container.
         // After this, validations are only applied by keyed/unkeyed containers and
         // by the leaf node methods of the single value container.
-        validator.applyValidations(to: self)
+//        validator.applyValidations(to: self)
         try container.encode(self)
 
         let errors: [ValidationError]

Sources/OpenAPIKit30/Validator/Validation.swift

@@ -109,7 +109,7 @@ public struct Validation<Subject: Validatable> {
 
 /// Validation errors are just a textual reason for validation failure and
 /// a coding path where the validation error occurred.
-public struct ValidationError: Swift.Error, CustomStringConvertible {
+public struct ValidationError: Swift.Error, CustomStringConvertible, PathContextError {
     /// The reason for the validation failure.
     public let reason: String
     /// The location where the failure occurred.
@@ -149,6 +149,7 @@ public struct ValidationErrorCollection: Swift.Error, CustomStringConvertible, E
     public var description: String { localizedDescription }
 
     public var swiftErrors: [Swift.Error] { values }
+    public var pathContextErrors: [PathContextError] { values }
 }
 
 /// Erases the type on which a `Validator` is specialized and combines

Sources/OpenAPIKitCore/Encoding and Decoding Errors And Warnings/OpenAPIDecodingErrors.swift

@@ -28,7 +28,16 @@ public enum ErrorCategory {
     }
 }
 
-public protocol OpenAPIError: Swift.Error, CustomStringConvertible {
+public protocol PathContextError {
+    /// The complete coding path for where the error occurred.
+    ///
+    /// This will often overlap with the `contextString` but there is not
+    /// a 1-1 relationship between the two. This is the same concept of
+    /// "codingPath" as is used elsewhere for the Swift `Codable` featureset.
+    var codingPath: [CodingKey] { get }
+}
+
+public protocol OpenAPIError: Swift.Error, CustomStringConvertible, PathContextError {
     /// The subject of the error (i.e. the thing being worked with
     ///     when the error occurred).
     ///
@@ -52,12 +61,6 @@ public protocol OpenAPIError: Swift.Error, CustomStringConvertible {
     ///     key in Document.info but it is missing." the **category** is
     ///     `.missing(.key)`.
     var errorCategory: ErrorCategory { get }
-    /// The complete coding path for where the error occurred.
-    ///
-    /// This will often overlap with the `contextString` but there is not
-    /// a 1-1 relationship between the two. This is the same concept of
-    /// "codingPath" as is used elsewhere for the Swift `Codable` featureset.
-    var codingPath: [CodingKey] { get }
 }
 
 public extension OpenAPIError {
@@ -121,6 +124,7 @@ public extension OpenAPIError {
 
 public protocol ErrorCollection {
     var swiftErrors: [Swift.Error] { get }
+    var pathContextErrors: [PathContextError] { get }
 
     var localizedDescription: String { get }
 }

Sources/OpenAPIKitCore/Encoding and Decoding Errors And Warnings/OpenAPIError.swift

@@ -46,7 +46,12 @@ public struct Error: Swift.Error, CustomStringConvertible {
 
         } else if let errorCollection = underlyingError as? ErrorCollection {
             localizedDescription = errorCollection.localizedDescription
-            codingPath = []
+            if errorCollection.pathContextErrors.count == 1,
+               let error = errorCollection.pathContextErrors.first {
+                codingPath = error.codingPath
+            } else {
+                codingPath = []
+            }
 
         } else {
             localizedDescription = underlyingError.localizedDescription

Tests/OpenAPIKitTests/Validator/BuiltinValidationTests.swift

@@ -22,9 +22,14 @@ final class BuiltinValidationTests: XCTestCase {
         let validator = Validator.blank.validating(.documentContainsPaths)
 
         XCTAssertThrowsError(try document.validate(using: validator)) { error in
-            let error = error as? ValidationErrorCollection
-            XCTAssertEqual(error?.values.first?.reason, "Failed to satisfy: Document contains at least one path")
-            XCTAssertEqual(error?.values.first?.codingPath.map { $0.stringValue }, [])
+            let errorCollection = error as? ValidationErrorCollection
+            XCTAssertEqual(errorCollection?.values.first?.reason, "Failed to satisfy: Document contains at least one path")
+            XCTAssertEqual(errorCollection?.values.first?.codingPath.map { $0.stringValue }, [])
+            XCTAssertEqual(errorCollection?.values.count, 1)
+
+            let openAPIError = OpenAPI.Error(from: error)
+            XCTAssertEqual(openAPIError.localizedDescription, "Failed to satisfy: Document contains at least one path at root of document")
+            XCTAssertEqual(openAPIError.codingPath.map { $0.stringValue }, [])
         }
     }
 
@@ -58,6 +63,7 @@ final class BuiltinValidationTests: XCTestCase {
             let error = error as? ValidationErrorCollection
             XCTAssertEqual(error?.values.first?.reason, "Failed to satisfy: Paths contain at least one operation")
             XCTAssertEqual(error?.values.first?.codingPath.map { $0.stringValue }, ["paths", "/hello/world"])
+            XCTAssertEqual(error?.values.count, 1)
         }
     }