refactor: allow internal validators infrastructure to throw

Author: kylef

Sources/Applicators/additionalItems.swift

@@ -1,13 +1,13 @@
-func additionalItems(context: Context, additionalItems: Any, instance: Any, schema: [String: Any]) -> AnySequence<ValidationError> {
+func additionalItems(context: Context, additionalItems: Any, instance: Any, schema: [String: Any]) throws -> AnySequence<ValidationError> {
   guard let instance = instance as? [Any], let items = schema["items"] as? [Any], instance.count > items.count else {
     return AnySequence(EmptyCollection())
   }
 
   if let additionalItems = additionalItems as? [String: Any] {
-    return AnySequence(Array(instance.enumerated())[items.count...].map { (index, subinstance) -> AnySequence<ValidationError> in
+    return try AnySequence(Array(instance.enumerated())[items.count...].map { (index, subinstance) throws -> AnySequence<ValidationError> in
       context.instanceLocation.push(index.description)
       defer { context.instanceLocation.pop() }
-      return context.descend(instance: subinstance, subschema: additionalItems)
+      return try context.descend(instance: subinstance, subschema: additionalItems)
     }.joined())
   }
 

Sources/Applicators/additionalProperties.swift

@@ -25,15 +25,17 @@ func findAdditionalProperties(instance: [String: Any], schema: [String: Any]) ->
 }
 
 
-func additionalProperties(context: Context, additionalProperties: Any, instance: Any, schema: [String: Any]) -> AnySequence<ValidationError> {
+func additionalProperties(context: Context, additionalProperties: Any, instance: Any, schema: [String: Any]) throws -> AnySequence<ValidationError> {
   guard let instance = instance as? [String: Any] else {
     return AnySequence(EmptyCollection())
   }
 
   let extras = findAdditionalProperties(instance: instance, schema: schema)
 
   if let additionalProperties = additionalProperties as? [String: Any] {
-    return AnySequence(extras.map { context.descend(instance: instance[$0]!, subschema: additionalProperties) }.joined())
+    return try AnySequence(extras.map {
+      try context.descend(instance: instance[$0]!, subschema: additionalProperties)
+    }.joined())
   }
 
   if let additionalProperties = additionalProperties as? Bool, !additionalProperties && !extras.isEmpty {

Sources/Applicators/allOf.swift

@@ -1,7 +1,9 @@
-func allOf(context: Context, allOf: Any, instance: Any, schema: [String: Any]) -> AnySequence<ValidationError> {
+func allOf(context: Context, allOf: Any, instance: Any, schema: [String: Any]) throws -> AnySequence<ValidationError> {
   guard let allOf = allOf as? [Any] else {
     return AnySequence(EmptyCollection())
   }
 
-  return AnySequence(allOf.map({ context.descend(instance: instance, subschema: $0) }).joined())
+  return try AnySequence(allOf.map({
+    try context.descend(instance: instance, subschema: $0)
+  }).joined())
 }

Sources/Applicators/anyOf.swift

@@ -1,9 +1,9 @@
-func anyOf(context: Context, anyOf: Any, instance: Any, schema: [String: Any]) -> AnySequence<ValidationError> {
+func anyOf(context: Context, anyOf: Any, instance: Any, schema: [String: Any]) throws -> AnySequence<ValidationError> {
   guard let anyOf = anyOf as? [Any] else {
     return AnySequence(EmptyCollection())
   }
 
-  if !anyOf.contains(where: { context.descend(instance: instance, subschema: $0).isValid }) {
+  if try !anyOf.contains(where: { try context.descend(instance: instance, subschema: $0).isValid }) {
     return AnySequence([
       ValidationError(
         "\(instance) does not meet anyOf validation rules.",

Sources/Applicators/contains.swift

@@ -1,4 +1,4 @@
-func contains(context: Context, contains: Any, instance: Any, schema: [String: Any]) -> AnySequence<ValidationError> {
+func contains(context: Context, contains: Any, instance: Any, schema: [String: Any]) throws -> AnySequence<ValidationError> {
   guard let instance = instance as? [Any] else {
     return AnySequence(EmptyCollection())
   }
@@ -22,10 +22,10 @@ func contains(context: Context, contains: Any, instance: Any, schema: [String: A
     return AnySequence(EmptyCollection())
   }
 
-  let containsCount = Array(instance.enumerated()).filter({ (index, subinstance) -> Bool in
+  let containsCount = try Array(instance.enumerated()).filter({ (index, subinstance) throws -> Bool in
     context.instanceLocation.push(index.description)
     defer { context.instanceLocation.pop() }
-    return context.descend(instance: subinstance, subschema: contains).isValid
+    return try context.descend(instance: subinstance, subschema: contains).isValid
   }).count
   if let max = max, containsCount > max {
     return AnySequence([

Sources/Applicators/dependencies.swift

@@ -1,4 +1,4 @@
-func dependencies(context: Context, dependencies: Any, instance: Any, schema: [String: Any]) -> AnySequence<ValidationError> {
+func dependencies(context: Context, dependencies: Any, instance: Any, schema: [String: Any]) throws -> AnySequence<ValidationError> {
   guard let dependencies = dependencies as? [String: Any] else {
     return AnySequence(EmptyCollection())
   }
@@ -22,7 +22,7 @@ func dependencies(context: Context, dependencies: Any, instance: Any, schema: [S
         }
       }
     } else {
-      results.append(context.descend(instance: instance, subschema: dependency))
+      results.append(try context.descend(instance: instance, subschema: dependency))
     }
   }
 

Sources/Applicators/dependentSchemas.swift

@@ -1,4 +1,4 @@
-func dependentSchemas(context: Context, dependentRequired: Any, instance: Any, schema: [String: Any]) -> AnySequence<ValidationError> {
+func dependentSchemas(context: Context, dependentRequired: Any, instance: Any, schema: [String: Any]) throws -> AnySequence<ValidationError> {
   guard let instance = instance as? [String: Any] else {
     return AnySequence(EmptyCollection())
   }
@@ -7,9 +7,9 @@ func dependentSchemas(context: Context, dependentRequired: Any, instance: Any, s
     return AnySequence(EmptyCollection())
   }
 
-  return AnySequence(dependentRequired.compactMap({ (key, subschema) -> AnySequence<ValidationError> in
+  return try AnySequence(dependentRequired.compactMap({ (key, subschema) throws -> AnySequence<ValidationError> in
     if instance.keys.contains(key) {
-      return context.descend(instance: instance, subschema: subschema)
+      return try context.descend(instance: instance, subschema: subschema)
     }
 
     return AnySequence(EmptyCollection())

Sources/Applicators/if.swift

@@ -1,10 +1,10 @@
-func `if`(context: Context, `if`: Any, instance: Any, schema: [String: Any]) -> AnySequence<ValidationError> {
-  if context.validate(instance: instance, schema: `if`).isValid {
+func `if`(context: Context, `if`: Any, instance: Any, schema: [String: Any]) throws -> AnySequence<ValidationError> {
+  if try context.validate(instance: instance, schema: `if`).isValid {
     if let then = schema["then"] {
-      return context.descend(instance: instance, subschema: then)
+      return try context.descend(instance: instance, subschema: then)
     }
   } else if let `else` = schema["else"] {
-    return context.descend(instance: instance, subschema: `else`)
+    return try context.descend(instance: instance, subschema: `else`)
   }
 
   return AnySequence(EmptyCollection())

Sources/Applicators/items.swift

@@ -1,21 +1,21 @@
-func items(context: Context, items: Any, instance: Any, schema: [String: Any]) -> AnySequence<ValidationError> {
+func items(context: Context, items: Any, instance: Any, schema: [String: Any]) throws -> AnySequence<ValidationError> {
   guard let instance = instance as? [Any] else {
     return AnySequence(EmptyCollection())
   }
 
   if let items = items as? [String: Any] {
-    return AnySequence(Array(instance.enumerated()).map { (index, instance) -> AnySequence<ValidationError> in
+    return try AnySequence(Array(instance.enumerated()).map { (index, instance) throws -> AnySequence<ValidationError> in
       context.instanceLocation.push(index.description)
       defer { context.instanceLocation.pop() }
-      return context.descend(instance: instance, subschema: items)
+      return try context.descend(instance: instance, subschema: items)
     }.joined())
   }
 
   if let items = items as? Bool {
-    return AnySequence(Array(instance.enumerated()).map { (index, instance) -> AnySequence<ValidationError> in
+    return try AnySequence(Array(instance.enumerated()).map { (index, instance) throws -> AnySequence<ValidationError> in
       context.instanceLocation.push(index.description)
       defer { context.instanceLocation.pop() }
-      return context.descend(instance: instance, subschema: items)
+      return try context.descend(instance: instance, subschema: items)
     }.joined())
   }
 
@@ -24,8 +24,8 @@ func items(context: Context, items: Any, instance: Any, schema: [String: Any]) -
 
     for (index, item) in instance.enumerated() where index < items.count {
       context.instanceLocation.push(index.description)
-      results.append(context.descend(instance: item, subschema: items[index]))
-      context.instanceLocation.pop()
+      defer { context.instanceLocation.pop() }
+      results.append(try context.descend(instance: item, subschema: items[index]))
     }
 
     return AnySequence(results.joined())

Sources/Applicators/not.swift

@@ -1,5 +1,5 @@
-func not(context: Context, not: Any, instance: Any, schema: [String: Any]) -> AnySequence<ValidationError> {
-  guard context.descend(instance: instance, subschema: not).isValid else {
+func not(context: Context, not: Any, instance: Any, schema: [String: Any]) throws -> AnySequence<ValidationError> {
+  guard try context.descend(instance: instance, subschema: not).isValid else {
     return AnySequence(EmptyCollection())
   }
 

Sources/Applicators/oneOf.swift

@@ -1,9 +1,9 @@
-func oneOf(context: Context, oneOf: Any, instance: Any, schema: [String: Any]) -> AnySequence<ValidationError> {
+func oneOf(context: Context, oneOf: Any, instance: Any, schema: [String: Any]) throws -> AnySequence<ValidationError> {
   guard let oneOf = oneOf as? [Any] else {
     return AnySequence(EmptyCollection())
   }
 
-  if oneOf.filter({ context.descend(instance: instance, subschema: $0).isValid }).count != 1 {
+  if try oneOf.filter({ try context.descend(instance: instance, subschema: $0).isValid }).count != 1 {
     return AnySequence([
       ValidationError(
         "Only one value from `oneOf` should be met",

Sources/Applicators/patternProperties.swift

@@ -1,7 +1,7 @@
 import Foundation
 
 
-func patternProperties(context: Context, patternProperties: Any, instance: Any, schema: [String: Any]) -> AnySequence<ValidationError> {
+func patternProperties(context: Context, patternProperties: Any, instance: Any, schema: [String: Any]) throws -> AnySequence<ValidationError> {
   guard let instance = instance as? [String: Any] else {
     return AnySequence(EmptyCollection())
   }
@@ -21,8 +21,8 @@ func patternProperties(context: Context, patternProperties: Any, instance: Any,
 
       for key in keys {
         context.instanceLocation.push(key)
-        results.append(context.descend(instance: instance[key]!, subschema: schema))
-        context.instanceLocation.pop()
+        defer { context.instanceLocation.pop() }
+        results.append(try context.descend(instance: instance[key]!, subschema: schema))
       }
     } catch {
       return AnySequence([

Sources/Applicators/properties.swift

@@ -1,4 +1,4 @@
-func properties(context: Context, properties: Any, instance: Any, schema: [String: Any]) -> AnySequence<ValidationError> {
+func properties(context: Context, properties: Any, instance: Any, schema: [String: Any]) throws -> AnySequence<ValidationError> {
   guard let instance = instance as? [String: Any] else {
     return AnySequence(EmptyCollection())
   }
@@ -7,11 +7,11 @@ func properties(context: Context, properties: Any, instance: Any, schema: [Strin
     return AnySequence(EmptyCollection())
   }
 
-  return AnySequence(instance.map { (key, value) -> AnySequence<ValidationError> in
+  return try AnySequence(instance.map { (key, value) throws -> AnySequence<ValidationError> in
     if let schema = properties[key] {
       context.instanceLocation.push(key)
       defer { context.instanceLocation.pop() }
-      return context.descend(instance: value, subschema: schema)
+      return try context.descend(instance: value, subschema: schema)
     }
 
     return AnySequence(EmptyCollection())

Sources/Applicators/propertyNames.swift

@@ -1,7 +1,9 @@
-func propertyNames(context: Context, propertyNames: Any, instance: Any, schema: [String: Any]) -> AnySequence<ValidationError> {
+func propertyNames(context: Context, propertyNames: Any, instance: Any, schema: [String: Any]) throws -> AnySequence<ValidationError> {
   guard let instance = instance as? [String: Any] else {
     return AnySequence(EmptyCollection())
   }
 
-  return AnySequence(instance.keys.map { context.descend(instance: $0, subschema: propertyNames) }.joined())
+  return try AnySequence(instance.keys.map {
+    try context.descend(instance: $0, subschema: propertyNames)
+  }.joined())
 }

Sources/Core/ref.swift

@@ -1,4 +1,4 @@
-func ref(context: Context, reference: Any, instance: Any, schema: [String: Any]) -> AnySequence<ValidationError> {
+func ref(context: Context, reference: Any, instance: Any, schema: [String: Any]) throws -> AnySequence<ValidationError> {
   guard let reference = reference as? String else {
     return AnySequence(EmptyCollection())
   }
@@ -28,5 +28,5 @@ func ref(context: Context, reference: Any, instance: Any, schema: [String: Any])
     }
   }
 
-  return context.descend(instance: instance, subschema: document)
+  return try context.descend(instance: instance, subschema: document)
 }

Sources/Validation/dependentRequired.swift

@@ -1,4 +1,4 @@
-func dependentRequired(context: Context, dependentRequired: Any, instance: Any, schema: [String: Any]) -> AnySequence<ValidationError> {
+func dependentRequired(context: Context, dependentRequired: Any, instance: Any, schema: [String: Any]) throws -> AnySequence<ValidationError> {
   guard let instance = instance as? [String: Any] else {
     return AnySequence(EmptyCollection())
   }
@@ -7,9 +7,9 @@ func dependentRequired(context: Context, dependentRequired: Any, instance: Any,
     return AnySequence(EmptyCollection())
   }
 
-  return AnySequence(dependentRequired.compactMap({ (key, required) -> AnySequence<ValidationError> in
+  return try AnySequence(dependentRequired.compactMap({ (key, required) -> AnySequence<ValidationError> in
     if instance.keys.contains(key) {
-      return JSONSchema.required(context: context, required: required, instance: instance, schema: schema)
+      return try JSONSchema.required(context: context, required: required, instance: instance, schema: schema)
     }
 
     return AnySequence(EmptyCollection())

Sources/Validation/required.swift

@@ -1,4 +1,4 @@
-func required(context: Context, required: Any, instance: Any, schema: [String: Any]) -> AnySequence<ValidationError> {
+func required(context: Context, required: Any, instance: Any, schema: [String: Any]) throws -> AnySequence<ValidationError> {
   guard let instance = instance as? [String: Any] else {
     return AnySequence(EmptyCollection())
   }

Sources/Validator.swift

@@ -11,7 +11,7 @@ class Context {
     self.validator = validator
   }
 
-  func validate(instance: Any, schema: Any) -> AnySequence<ValidationError> {
+  func validate(instance: Any, schema: Any) throws -> AnySequence<ValidationError> {
     if let schema = schema as? Bool {
       if schema == true {
         return AnySequence(EmptyCollection())
@@ -30,13 +30,13 @@ class Context {
       // Older versions of JSON Schema, $ref ignores any alongside keywords
       if let ref = schema["$ref"] as? String {
         let validation = validator.validations["$ref"]!
-        return validation(self, ref, instance, schema)
+        return try validation(self, ref, instance, schema)
       }
     }
 
-    return AnySequence(validator.validations.compactMap { (key, validation) -> AnySequence<ValidationError> in
+    return try AnySequence(validator.validations.compactMap { (key, validation) -> AnySequence<ValidationError> in
       if let value = schema[key] {
-        return validation(self, value, instance, schema)
+        return try validation(self, value, instance, schema)
       }
 
       return AnySequence(EmptyCollection())
@@ -47,13 +47,13 @@ class Context {
     return resolver.resolve(reference: ref)
   }
 
-  func descend(instance: Any, subschema: Any) -> AnySequence<ValidationError> {
-    return validate(instance: instance, schema: subschema)
+  func descend(instance: Any, subschema: Any) throws -> AnySequence<ValidationError> {
+    return try validate(instance: instance, schema: subschema)
   }
 }
 
 protocol Validator {
-  typealias Validation = (Context, Any, Any, [String: Any]) -> AnySequence<ValidationError>
+  typealias Validation = (Context, Any, Any, [String: Any]) throws -> AnySequence<ValidationError>
 
   var resolver: RefResolver { get }
 
@@ -66,11 +66,11 @@ protocol Validator {
 extension Validator {
   public func validate(instance: Any) throws -> ValidationResult {
     let context = Context(resolver: resolver, validator: self)
-    return context.validate(instance: instance, schema: schema).validationResult()
+    return try context.validate(instance: instance, schema: schema).validationResult()
   }
 
   public func validate(instance: Any) throws -> AnySequence<ValidationError> {
     let context = Context(resolver: resolver, validator: self)
-    return context.validate(instance: instance, schema: schema)
+    return try context.validate(instance: instance, schema: schema)
   }
 }

Sources/format.swift

@@ -1,7 +1,7 @@
 import Foundation
 
 
-func format(context: Context, format: Any, instance: Any, schema: [String: Any]) -> AnySequence<ValidationError> {
+func format(context: Context, format: Any, instance: Any, schema: [String: Any]) throws -> AnySequence<ValidationError> {
   guard let format = format as? String else {
     return AnySequence(EmptyCollection())
   }