feat: add dedupeEnums option

.changeset/wet-foxes-watch.md

@@ -0,0 +1,5 @@
+---
+"openapi-typescript": minor
+---
+
+feat: add dedupeEnums option

docs/cli.md

@@ -113,6 +113,7 @@ The following flags are supported in the CLI:
 | `--empty-objects-unknown`          |       | `false`  | Allow arbitrary properties for schema objects with no specified properties, and no specified `additionalProperties` |
 | `--enum`                           |       | `false`  | Generate true [TS enums](https://www.typescriptlang.org/docs/handbook/enums.html) rather than string unions.        |
 | `--enum-values`                    |       | `false`  | Export enum values as arrays.                                                                                       |
+| `--dedupe-enums`                   |       | `false`  | Dedupe enum types when `--enum=true` is set                                                                         |
 | `--check`                    |     | `false`  | Check that the generated types are up-to-date.                                                                              |
 | `--exclude-deprecated`             |       | `false`  | Exclude deprecated fields from types                                                                                |
 | `--export-type`                    | `-t`  | `false`  | Export `type` instead of `interface`                                                                                |

docs/zh/cli.md

@@ -112,7 +112,8 @@ CLI 支持以下参数：
 | `--empty-objects-unknown` |      | `false`  | 允许在未指定属性和未指定 `additionalProperties` 的情况下，为模式对象设置任意属性                  |
 | `--enum`                  |      | `false`  | 生成真实的 [TS 枚举](https://www.typescriptlang.org/docs/handbook/enums.html)，而不是字符串联合。 |
 | `--enum-values`            |      | `false`  | 将 enum 值导出为数组                                                                                                  |
-| `--check`            |      | `false`  | 检查生成的类型是否是最新的                                                   |
+| `--dedupe-enums`            |      | `false`  | 将 enum 值导出为数组                                                                                                  |
+| `--check`            |      | `false`  | 当 --enum=true 时，去除重复定义的枚举类型                                                   |
 | `--exclude-deprecated`    |      | `false`  | 从类型中排除已弃用的字段                                                                          |
 | `--export-type`           | `-t` | `false`  | 导出 `type` 而不是 `interface`                                                                    |
 | `--immutable`             |      | `false`  | 生成不可变类型（只读属性和只读数组）                                                              |

packages/openapi-typescript-helpers/package.json

@@ -23,12 +23,7 @@
     },
     "./*": "./*"
   },
-  "files": [
-    "index.js",
-    "index.cjs",
-    "index.d.ts",
-    "index.d.cts"
-  ],
+  "files": ["index.js", "index.cjs", "index.d.ts", "index.d.cts"],
   "homepage": "https://openapi-ts.dev",
   "repository": {
     "type": "git",

packages/openapi-typescript/bin/cli.js

@@ -17,6 +17,7 @@ Options
   --output, -o               Specify output file (if not specified in redocly.yaml)
   --enum                     Export true TS enums instead of unions
   --enum-values              Export enum values as arrays
+  --dedupe-enums             Dedupe enum types when \`--enum=true\` is set
   --check                    Check that the generated types are up-to-date. (default: false)
   --export-type, -t          Export top-level \`type\` instead of \`interface\`
   --immutable                Generate readonly types
@@ -66,6 +67,7 @@ const flags = parser(args, {
     "emptyObjectsUnknown",
     "enum",
     "enumValues",
+    "dedupeEnums",
     "check",
     "excludeDeprecated",
     "exportType",
@@ -126,6 +128,7 @@ async function generateSchema(schema, { redocly, silent = false }) {
       emptyObjectsUnknown: flags.emptyObjectsUnknown,
       enum: flags.enum,
       enumValues: flags.enumValues,
+      dedupeEnums: flags.dedupeEnums,
       excludeDeprecated: flags.excludeDeprecated,
       exportType: flags.exportType,
       immutable: flags.immutable,

packages/openapi-typescript/src/index.ts

@@ -75,6 +75,7 @@ export default async function openapiTS(
     emptyObjectsUnknown: options.emptyObjectsUnknown ?? false,
     enum: options.enum ?? false,
     enumValues: options.enumValues ?? false,
+    dedupeEnums: options.dedupeEnums ?? false,
     excludeDeprecated: options.excludeDeprecated ?? false,
     exportType: options.exportType ?? false,
     immutable: options.immutable ?? false,

packages/openapi-typescript/src/lib/ts.ts

@@ -204,20 +204,37 @@ export function tsDedupe(types: ts.TypeNode[]): ts.TypeNode[] {
   return filteredTypes;
 }
 
+export const enumCache = new Map<string, ts.EnumDeclaration>();
+
 /** Create a TS enum (with sanitized name and members) */
 export function tsEnum(
   name: string,
   members: (string | number)[],
   metadata?: { name?: string; description?: string }[],
-  options?: { export?: boolean },
+  options?: { export?: boolean; shouldCache?: boolean },
 ) {
   let enumName = sanitizeMemberName(name);
   enumName = `${enumName[0].toUpperCase()}${enumName.substring(1)}`;
-  return ts.factory.createEnumDeclaration(
+  let key = "";
+  if (options?.shouldCache) {
+    key = `${members
+      .slice(0)
+      .sort()
+      .map((v, i) => {
+        return `${metadata?.[i]?.name ?? String(v)}:${metadata?.[i]?.description || ""}`;
+      })
+      .join(",")}`;
+    if (enumCache.has(key)) {
+      return enumCache.get(key) as ts.EnumDeclaration;
+    }
+  }
+  const enumDeclaration = ts.factory.createEnumDeclaration(
     /* modifiers */ options ? tsModifiers({ export: options.export ?? false }) : undefined,
     /* name      */ enumName,
     /* members   */ members.map((value, i) => tsEnumMember(value, metadata?.[i])),
   );
+  options?.shouldCache && enumCache.set(key, enumDeclaration);
+  return enumDeclaration;
 }
 
 /** Create an exported TS array literal expression  */

packages/openapi-typescript/src/transform/schema-object.ts

@@ -102,17 +102,14 @@ export function transformSchemaObjectWithComposition(
         name: schemaObject["x-enum-varnames"]?.[i] ?? schemaObject["x-enumNames"]?.[i],
         description: schemaObject["x-enum-descriptions"]?.[i] ?? schemaObject["x-enumDescriptions"]?.[i],
       }));
-      const enumType = tsEnum(
-        enumName,
-        schemaObject.enum as (string | number)[],
-        metadata,
-
-        {
-          export: true,
-          // readonly: TS enum do not support the readonly modifier
-        },
-      );
-      options.ctx.injectFooter.push(enumType);
+      const enumType = tsEnum(enumName, schemaObject.enum as (string | number)[], metadata, {
+        shouldCache: options.ctx.dedupeEnums,
+        export: true,
+        // readonly: TS enum do not support the readonly modifier
+      });
+      if (!options.ctx.injectFooter.includes(enumType)) {
+        options.ctx.injectFooter.push(enumType);
+      }
       return ts.factory.createTypeReferenceNode(enumType.name);
     }
     const enumType = schemaObject.enum.map(tsLiteral);

packages/openapi-typescript/src/types.ts

@@ -651,6 +651,8 @@ export interface OpenAPITSOptions {
   enum?: boolean;
   /** Export union values as arrays */
   enumValues?: boolean;
+  /** Dedupe enum values */
+  dedupeEnums?: boolean;
   /** (optional) Substitute path parameter names with their respective types */
   pathParamsAsTypes?: boolean;
   /** Treat all objects as if they have \`required\` set to all properties by default (default: false) */
@@ -678,6 +680,7 @@ export interface GlobalContext {
   emptyObjectsUnknown: boolean;
   enum: boolean;
   enumValues: boolean;
+  dedupeEnums: boolean;
   excludeDeprecated: boolean;
   exportType: boolean;
   immutable: boolean;

packages/openapi-typescript/test/node-api.test.ts

@@ -804,6 +804,93 @@ export type operations = Record<string, never>;`,
         options: { enumValues: true },
       },
     ],
+    [
+      "options > dedupeEnums",
+      {
+        given: {
+          openapi: "3.1",
+          info: { title: "Test", version: "1.0" },
+          paths: {
+            "/url": {
+              get: {
+                parameters: [
+                  {
+                    name: "status",
+                    in: "query",
+                    schema: {
+                      type: "string",
+                      enum: ["active", "inactive"],
+                    },
+                  },
+                ],
+              },
+            },
+          },
+          components: {
+            schemas: {
+              Status: {
+                type: "string",
+                enum: ["active", "inactive"],
+              },
+              StatusReverse: {
+                type: "string",
+                enum: ["inactive", "active"],
+              },
+            },
+          },
+        },
+        want: `export interface paths {
+    "/url": {
+        parameters: {
+            query?: never;
+            header?: never;
+            path?: never;
+            cookie?: never;
+        };
+        get: {
+            parameters: {
+                query?: {
+                    status?: PathsUrlGetParametersQueryStatus;
+                };
+                header?: never;
+                path?: never;
+                cookie?: never;
+            };
+            requestBody?: never;
+            responses: never;
+        };
+        put?: never;
+        post?: never;
+        delete?: never;
+        options?: never;
+        head?: never;
+        patch?: never;
+        trace?: never;
+    };
+}
+export type webhooks = Record<string, never>;
+export interface components {
+    schemas: {
+        /** @enum {string} */
+        Status: PathsUrlGetParametersQueryStatus;
+        /** @enum {string} */
+        StatusReverse: PathsUrlGetParametersQueryStatus;
+    };
+    responses: never;
+    parameters: never;
+    requestBodies: never;
+    headers: never;
+    pathItems: never;
+}
+export type $defs = Record<string, never>;
+export enum PathsUrlGetParametersQueryStatus {
+    active = "active",
+    inactive = "inactive"
+}
+export type operations = Record<string, never>;`,
+        options: { enum: true, dedupeEnums: true },
+      },
+    ],
     [
       "snapshot > GitHub",
       {

packages/openapi-typescript/test/test-helpers.ts

@@ -15,6 +15,7 @@ export const DEFAULT_CTX: GlobalContext = {
   emptyObjectsUnknown: false,
   enum: false,
   enumValues: false,
+  dedupeEnums: false,
   excludeDeprecated: false,
   exportType: false,
   immutable: false,