Add swift5 option for generating frozen enums

bin/configs/swift5-frozenEnums.yaml

@@ -0,0 +1,12 @@
+generatorName: swift5
+outputDir: samples/client/petstore/swift5/frozenEnums
+inputSpec: modules/openapi-generator/src/test/resources/2_0/swift/petstore-with-fake-endpoints-models-for-testing.yaml
+templateDir: modules/openapi-generator/src/main/resources/swift5
+generateAliasAsModel: true
+additionalProperties:
+  podAuthors: ""
+  podSummary: PetstoreClient
+  sortParamsByRequiredFlag: false
+  generateFrozenEnums: false
+  projectName: PetstoreClient
+  podHomepage: https://github.com/openapitools/openapi-generator

docs/generators/swift5.md

@@ -11,6 +11,7 @@ These options may be applied as additional-properties (cli) or configOptions (pl
 |apiNamePrefix|Prefix that will be appended to all API names ('tags'). Default: empty string. e.g. Pet => Pet.| |null|
 |disallowAdditionalPropertiesIfNotPresent|If false, the 'additionalProperties' implementation (set to true by default) is compliant with the OAS and JSON schema specifications. If true (default), keep the old (incorrect) behaviour that 'additionalProperties' is set to false by default.|<dl><dt>**false**</dt><dd>The 'additionalProperties' implementation is compliant with the OAS and JSON schema specifications.</dd><dt>**true**</dt><dd>Keep the old (incorrect) behaviour that 'additionalProperties' is set to false by default.</dd></dl>|true|
 |ensureUniqueParams|Whether to ensure parameter names are unique in an operation (rename parameters that are not).| |true|
+|generateFrozenEnums|Generate model enums that are "frozen". A frozen enum strictly represents the cases described in the spec, and nothing else. A non-frozen enum includes an unknown case that can represent future cases not yet described in the spec. (default: true)| |true|
 |generateModelAdditionalProperties|Generate model additional properties (default: true)| |true|
 |hashableModels|Make hashable models (default: true)| |true|
 |hideGenerationTimestamp|Hides the generation timestamp when files are generated.| |true|

modules/openapi-generator/src/main/java/org/openapitools/codegen/languages/Swift5ClientCodegen.java

@@ -66,6 +66,7 @@ public class Swift5ClientCodegen extends DefaultCodegen implements CodegenConfig
     public static final String SWIFT_PACKAGE_PATH = "swiftPackagePath";
     public static final String USE_CLASSES = "useClasses";
     public static final String USE_BACKTICK_ESCAPES = "useBacktickEscapes";
+    public static final String GENERATE_FROZEN_ENUMS = "generateFrozenEnums";
     public static final String GENERATE_MODEL_ADDITIONAL_PROPERTIES = "generateModelAdditionalProperties";
     public static final String HASHABLE_MODELS = "hashableModels";
     public static final String MAP_FILE_BINARY_TO_DATA = "mapFileBinaryToData";
@@ -90,6 +91,7 @@ public class Swift5ClientCodegen extends DefaultCodegen implements CodegenConfig
     protected boolean useClasses = false;
     protected boolean useBacktickEscapes = false;
     protected boolean generateModelAdditionalProperties = true;
+    protected boolean generateFrozenEnums = true;
     protected boolean hashableModels = true;
     protected boolean mapFileBinaryToData = false;
     protected String[] responseAs = new String[0];
@@ -281,6 +283,9 @@ public Swift5ClientCodegen() {
         cliOptions.add(new CliOption(USE_BACKTICK_ESCAPES,
                 "Escape reserved words using backticks (default: false)")
                 .defaultValue(Boolean.FALSE.toString()));
+        cliOptions.add(new CliOption(GENERATE_FROZEN_ENUMS,
+                "Generate frozen enums (default: true)")
+                .defaultValue(Boolean.TRUE.toString()));
         cliOptions.add(new CliOption(GENERATE_MODEL_ADDITIONAL_PROPERTIES,
                 "Generate model additional properties (default: true)")
                 .defaultValue(Boolean.TRUE.toString()));
@@ -485,6 +490,13 @@ public void processOpts() {
             setUseBacktickEscapes(convertPropertyToBooleanAndWriteBack(USE_BACKTICK_ESCAPES));
         }
 
+        // Setup generateFrozenEnums option. If true, enums will strictly include
+        // cases matching the spec. If false, enums will also include an extra catch-all case.
+        if (additionalProperties.containsKey(GENERATE_FROZEN_ENUMS)) {
+            setGenerateFrozenEnums(convertPropertyToBooleanAndWriteBack(GENERATE_FROZEN_ENUMS));
+        }
+        additionalProperties.put(GENERATE_FROZEN_ENUMS, generateFrozenEnums);
+
         if (additionalProperties.containsKey(GENERATE_MODEL_ADDITIONAL_PROPERTIES)) {
             setGenerateModelAdditionalProperties(convertPropertyToBooleanAndWriteBack(GENERATE_MODEL_ADDITIONAL_PROPERTIES));
         }
@@ -943,6 +955,10 @@ public void setUseBacktickEscapes(boolean useBacktickEscapes) {
         this.useBacktickEscapes = useBacktickEscapes;
     }
 
+    public void setGenerateFrozenEnums(boolean generateFrozenEnums) {
+        this.generateFrozenEnums = generateFrozenEnums;
+    }
+
     public void setGenerateModelAdditionalProperties(boolean generateModelAdditionalProperties) {
         this.generateModelAdditionalProperties = generateModelAdditionalProperties;
     }

modules/openapi-generator/src/main/resources/swift5/Models.mustache

@@ -14,6 +14,28 @@ extension JSONEncodable {
     func encodeToJSON() -> Any { self }
 }
 
+/// An enum where the last case value can be used as a default catch-all.
+protocol CaseIterableDefaultsLast: Decodable & CaseIterable & RawRepresentable
+where RawValue: Decodable, AllCases: BidirectionalCollection {}
+
+extension CaseIterableDefaultsLast {
+    /// Initializes an enum such that if a known raw value is found, then it is decoded.
+    /// Otherwise the last case is used.
+    /// - Parameter decoder: A decoder.
+    public init(from decoder: Decoder) throws {
+        if let value = try Self(rawValue: decoder.singleValueContainer().decode(RawValue.self)) {
+            self = value
+        } else if let lastValue = Self.allCases.last {
+            self = lastValue
+        } else {
+            throw DecodingError.valueNotFound(
+                Self.Type.self,
+                .init(codingPath: decoder.codingPath, debugDescription: "CaseIterableDefaultsLast")
+            )
+        }
+    }
+}
+
 {{#nonPublicApi}}internal{{/nonPublicApi}}{{^nonPublicApi}}public{{/nonPublicApi}} enum ErrorResponse: Error {
     case error(Int, Data?, URLResponse?, Error)
 }

modules/openapi-generator/src/main/resources/swift5/modelEnum.mustache

@@ -1,7 +1,32 @@
-{{#nonPublicApi}}internal{{/nonPublicApi}}{{^nonPublicApi}}public{{/nonPublicApi}} enum {{classname}}: {{dataType}}, {{#useVapor}}Content, Hashable{{/useVapor}}{{^useVapor}}Codable{{/useVapor}}, CaseIterable {
+{{#nonPublicApi}}internal{{/nonPublicApi}}{{^nonPublicApi}}public{{/nonPublicApi}} enum {{classname}}: {{dataType}}, {{#useVapor}}Content, Hashable{{/useVapor}}{{^useVapor}}Codable{{/useVapor}}, CaseIterable{{^generateFrozenEnums}}{{#isInteger}}, CaseIterableDefaultsLast{{/isInteger}}{{#isFloat}}, CaseIterableDefaultsLast{{/isFloat}}{{#isDouble}}, CaseIterableDefaultsLast{{/isDouble}}{{#isString}}, CaseIterableDefaultsLast{{/isString}}{{/generateFrozenEnums}} {
 {{#allowableValues}}
 {{#enumVars}}
     case {{{name}}} = {{{value}}}
 {{/enumVars}}
 {{/allowableValues}}
+{{^generateFrozenEnums}}
+    // This case is a catch-all generated by OpenAPI such that the enum is "non-frozen".
+    // If new enum cases are added that are unknown to the spec/client, they are safely
+    // decoded to this case. The raw value of this case is a dummy value that attempts
+    // to avoids collisions with previously specified cases.
+{{#isString}}
+    case unknownDefaultOpenAPI = "unknown_default_open_api"
+{{/isString}}
+{{#isNumeric}}
+    //
+    // 192, used to calculate the raw value, was the Swift Evolution proposal for
+    // frozen/non-frozen enums.
+    // [SE-0192](https://github.com/apple/swift-evolution/blob/master/proposals/0192-non-exhaustive-enums.md)
+    //
+{{/isNumeric}}
+{{#isInteger}}
+    case unknownDefaultOpenAPI = -11184809 // Int.min / 192
+{{/isInteger}}
+{{#isDouble}}
+    case unknownDefaultOpenAPI = -11184809 // Int.min / 192
+{{/isDouble}}
+{{#isFloat}}
+    case unknownDefaultOpenAPI = -11184809 // Int.min / 192
+{{/isFloat}}
+{{/generateFrozenEnums}}
 }

modules/openapi-generator/src/main/resources/swift5/modelInlineEnumDeclaration.mustache

@@ -1,7 +1,35 @@
-    {{#nonPublicApi}}internal{{/nonPublicApi}}{{^nonPublicApi}}public{{/nonPublicApi}} enum {{enumName}}: {{^isContainer}}{{dataType}}{{/isContainer}}{{#isContainer}}String{{/isContainer}}, {{#useVapor}}Content, Hashable{{/useVapor}}{{^useVapor}}Codable{{/useVapor}}, CaseIterable {
+    {{#nonPublicApi}}internal{{/nonPublicApi}}{{^nonPublicApi}}public{{/nonPublicApi}} enum {{enumName}}: {{^isContainer}}{{dataType}}{{/isContainer}}{{#isContainer}}String{{/isContainer}}, {{#useVapor}}Content, Hashable{{/useVapor}}{{^useVapor}}Codable{{/useVapor}}, CaseIterable{{^generateFrozenEnums}}{{#isInteger}}, CaseIterableDefaultsLast{{/isInteger}}{{#isFloat}}, CaseIterableDefaultsLast{{/isFloat}}{{#isDouble}}, CaseIterableDefaultsLast{{/isDouble}}{{#isString}}, CaseIterableDefaultsLast{{/isString}}{{#isContainer}}, CaseIterableDefaultsLast{{/isContainer}}{{/generateFrozenEnums}} {
         {{#allowableValues}}
         {{#enumVars}}
         case {{{name}}} = {{{value}}}
         {{/enumVars}}
         {{/allowableValues}}
+        {{^generateFrozenEnums}}
+        // This case is a catch-all generated by OpenAPI such that the enum is "non-frozen".
+        // If new enum cases are added that are unknown to the spec/client, they are safely
+        // decoded to this case. The raw value of this case is a dummy value that attempts
+        // to avoids collisions with previously specified cases.
+        {{#isString}}
+        case unknownDefaultOpenAPI = "unknown_default_open_api"
+        {{/isString}}
+        {{#isContainer}}
+        case unknownDefaultOpenAPI = "unknown_default_open_api"
+        {{/isContainer}}
+        {{#isNumeric}}
+        //
+        // 192, used to calculate the raw value, was the Swift Evolution proposal for
+        // frozen/non-frozen enums.
+        // [SE-0192](https://github.com/apple/swift-evolution/blob/master/proposals/0192-non-exhaustive-enums.md)
+        //
+        {{/isNumeric}}
+        {{#isInteger}}
+        case unknownDefaultOpenAPI = -11184809 // Int.min / 192
+        {{/isInteger}}
+        {{#isDouble}}
+        case unknownDefaultOpenAPI = -11184809 // Int.min / 192
+        {{/isDouble}}
+        {{#isFloat}}
+        case unknownDefaultOpenAPI = -11184809 // Int.min / 192
+        {{/isFloat}}
+        {{/generateFrozenEnums}}
     }

modules/openapi-generator/src/test/java/org/openapitools/codegen/options/Swift5OptionsProvider.java

@@ -48,6 +48,7 @@ public class Swift5OptionsProvider implements OptionsProvider {
     public static final String REMOVE_MIGRATION_PROJECT_NAME_CLASS_VALUE = "false";
     public static final String SWIFT_USE_API_NAMESPACE_VALUE = "swiftUseApiNamespace";
     public static final String USE_BACKTICKS_ESCAPES_VALUE = "false";
+    public static final String GENERATE_FROZEN_ENUMS_VALUE = "true";
     public static final String GENERATE_MODEL_ADDITIONAL_PROPERTIES_VALUE = "true";
     public static final String HASHABLE_MODELS_VALUE = "true";
     public static final String ALLOW_UNICODE_IDENTIFIERS_VALUE = "false";
@@ -95,6 +96,7 @@ public Map<String, String> createOptions() {
                 .put(CodegenConstants.DISALLOW_ADDITIONAL_PROPERTIES_IF_NOT_PRESENT, "true")
                 .put(Swift5ClientCodegen.USE_SPM_FILE_STRUCTURE, USE_SPM_FILE_STRUCTURE_VALUE)
                 .put(Swift5ClientCodegen.SWIFT_PACKAGE_PATH, SWIFT_PACKAGE_PATH_VALUE)
+                .put(Swift5ClientCodegen.GENERATE_FROZEN_ENUMS, GENERATE_FROZEN_ENUMS_VALUE)
                 .put(Swift5ClientCodegen.GENERATE_MODEL_ADDITIONAL_PROPERTIES, GENERATE_MODEL_ADDITIONAL_PROPERTIES_VALUE)
                 .put(Swift5ClientCodegen.HASHABLE_MODELS, HASHABLE_MODELS_VALUE)
                 .put(Swift5ClientCodegen.MAP_FILE_BINARY_TO_DATA, "false")

modules/openapi-generator/src/test/java/org/openapitools/codegen/swift5/Swift5OptionsTest.java

@@ -49,6 +49,7 @@ protected void verifyOptions() {
         verify(clientCodegen).setPrependFormOrBodyParameters(Boolean.valueOf(Swift5OptionsProvider.PREPEND_FORM_OR_BODY_PARAMETERS_VALUE));
         verify(clientCodegen).setReadonlyProperties(Boolean.parseBoolean(Swift5OptionsProvider.READONLY_PROPERTIES_VALUE));
         verify(clientCodegen).setRemoveMigrationProjectNameClass(Boolean.parseBoolean(Swift5OptionsProvider.REMOVE_MIGRATION_PROJECT_NAME_CLASS_VALUE));
+        verify(clientCodegen).setGenerateFrozenEnums(Boolean.parseBoolean(Swift5OptionsProvider.GENERATE_FROZEN_ENUMS_VALUE));
         verify(clientCodegen).setGenerateModelAdditionalProperties(Boolean.parseBoolean(Swift5OptionsProvider.GENERATE_MODEL_ADDITIONAL_PROPERTIES_VALUE));
         verify(clientCodegen).setHashableModels(Boolean.parseBoolean(Swift5OptionsProvider.HASHABLE_MODELS_VALUE));
     }

pom.xml

@@ -1434,6 +1434,7 @@
                 <module>samples/client/petstore/swift5/combineLibrary</module>
                 <module>samples/client/petstore/swift5/default</module>
                 <module>samples/client/petstore/swift5/deprecated</module>
+                <module>samples/client/petstore/swift5/frozenEnums</module>
                 <module>samples/client/petstore/swift5/nonPublicApi</module>
                 <module>samples/client/petstore/swift5/objcCompatible</module>
                 <module>samples/client/petstore/swift5/promisekitLibrary</module>

samples/client/petstore/swift5/alamofireLibrary/PetstoreClient/Classes/OpenAPIs/Models.swift

@@ -14,6 +14,28 @@ extension JSONEncodable {
     func encodeToJSON() -> Any { self }
 }
 
+/// An enum where the last case value can be used as a default catch-all.
+protocol CaseIterableDefaultsLast: Decodable & CaseIterable & RawRepresentable
+where RawValue: Decodable, AllCases: BidirectionalCollection {}
+
+extension CaseIterableDefaultsLast {
+    /// Initializes an enum such that if a known raw value is found, then it is decoded.
+    /// Otherwise the last case is used.
+    /// - Parameter decoder: A decoder.
+    public init(from decoder: Decoder) throws {
+        if let value = try Self(rawValue: decoder.singleValueContainer().decode(RawValue.self)) {
+            self = value
+        } else if let lastValue = Self.allCases.last {
+            self = lastValue
+        } else {
+            throw DecodingError.valueNotFound(
+                Self.Type.self,
+                .init(codingPath: decoder.codingPath, debugDescription: "CaseIterableDefaultsLast")
+            )
+        }
+    }
+}
+
 public enum ErrorResponse: Error {
     case error(Int, Data?, URLResponse?, Error)
 }

samples/client/petstore/swift5/asyncAwaitLibrary/PetstoreClient/Classes/OpenAPIs/Models.swift

@@ -14,6 +14,28 @@ extension JSONEncodable {
     func encodeToJSON() -> Any { self }
 }
 
+/// An enum where the last case value can be used as a default catch-all.
+protocol CaseIterableDefaultsLast: Decodable & CaseIterable & RawRepresentable
+where RawValue: Decodable, AllCases: BidirectionalCollection {}
+
+extension CaseIterableDefaultsLast {
+    /// Initializes an enum such that if a known raw value is found, then it is decoded.
+    /// Otherwise the last case is used.
+    /// - Parameter decoder: A decoder.
+    public init(from decoder: Decoder) throws {
+        if let value = try Self(rawValue: decoder.singleValueContainer().decode(RawValue.self)) {
+            self = value
+        } else if let lastValue = Self.allCases.last {
+            self = lastValue
+        } else {
+            throw DecodingError.valueNotFound(
+                Self.Type.self,
+                .init(codingPath: decoder.codingPath, debugDescription: "CaseIterableDefaultsLast")
+            )
+        }
+    }
+}
+
 public enum ErrorResponse: Error {
     case error(Int, Data?, URLResponse?, Error)
 }

samples/client/petstore/swift5/combineLibrary/PetstoreClient/Classes/OpenAPIs/Models.swift

@@ -14,6 +14,28 @@ extension JSONEncodable {
     func encodeToJSON() -> Any { self }
 }
 
+/// An enum where the last case value can be used as a default catch-all.
+protocol CaseIterableDefaultsLast: Decodable & CaseIterable & RawRepresentable
+where RawValue: Decodable, AllCases: BidirectionalCollection {}
+
+extension CaseIterableDefaultsLast {
+    /// Initializes an enum such that if a known raw value is found, then it is decoded.
+    /// Otherwise the last case is used.
+    /// - Parameter decoder: A decoder.
+    public init(from decoder: Decoder) throws {
+        if let value = try Self(rawValue: decoder.singleValueContainer().decode(RawValue.self)) {
+            self = value
+        } else if let lastValue = Self.allCases.last {
+            self = lastValue
+        } else {
+            throw DecodingError.valueNotFound(
+                Self.Type.self,
+                .init(codingPath: decoder.codingPath, debugDescription: "CaseIterableDefaultsLast")
+            )
+        }
+    }
+}
+
 public enum ErrorResponse: Error {
     case error(Int, Data?, URLResponse?, Error)
 }

samples/client/petstore/swift5/default/PetstoreClient/Classes/OpenAPIs/Models.swift

@@ -14,6 +14,28 @@ extension JSONEncodable {
     func encodeToJSON() -> Any { self }
 }
 
+/// An enum where the last case value can be used as a default catch-all.
+protocol CaseIterableDefaultsLast: Decodable & CaseIterable & RawRepresentable
+where RawValue: Decodable, AllCases: BidirectionalCollection {}
+
+extension CaseIterableDefaultsLast {
+    /// Initializes an enum such that if a known raw value is found, then it is decoded.
+    /// Otherwise the last case is used.
+    /// - Parameter decoder: A decoder.
+    public init(from decoder: Decoder) throws {
+        if let value = try Self(rawValue: decoder.singleValueContainer().decode(RawValue.self)) {
+            self = value
+        } else if let lastValue = Self.allCases.last {
+            self = lastValue
+        } else {
+            throw DecodingError.valueNotFound(
+                Self.Type.self,
+                .init(codingPath: decoder.codingPath, debugDescription: "CaseIterableDefaultsLast")
+            )
+        }
+    }
+}
+
 public enum ErrorResponse: Error {
     case error(Int, Data?, URLResponse?, Error)
 }

samples/client/petstore/swift5/deprecated/PetstoreClient/Classes/OpenAPIs/Models.swift

@@ -14,6 +14,28 @@ extension JSONEncodable {
     func encodeToJSON() -> Any { self }
 }
 
+/// An enum where the last case value can be used as a default catch-all.
+protocol CaseIterableDefaultsLast: Decodable & CaseIterable & RawRepresentable
+where RawValue: Decodable, AllCases: BidirectionalCollection {}
+
+extension CaseIterableDefaultsLast {
+    /// Initializes an enum such that if a known raw value is found, then it is decoded.
+    /// Otherwise the last case is used.
+    /// - Parameter decoder: A decoder.
+    public init(from decoder: Decoder) throws {
+        if let value = try Self(rawValue: decoder.singleValueContainer().decode(RawValue.self)) {
+            self = value
+        } else if let lastValue = Self.allCases.last {
+            self = lastValue
+        } else {
+            throw DecodingError.valueNotFound(
+                Self.Type.self,
+                .init(codingPath: decoder.codingPath, debugDescription: "CaseIterableDefaultsLast")
+            )
+        }
+    }
+}
+
 public enum ErrorResponse: Error {
     case error(Int, Data?, URLResponse?, Error)
 }