feat: Adding constant handling (#220)

* Adding constant handling.

* Add Kusmeroglu as contributor

---------

Co-authored-by: Fabien Bernard <[email protected]>

Author: Kusmeroglu

.all-contributorsrc

@@ -105,6 +105,13 @@
       "avatar_url": "https://avatars.githubusercontent.com/u/22816887?v=4",
       "profile": "https://github.com/dan-cooke",
       "contributions": ["bug", "code"]
+    },
+    {
+      "login": "Kusmeroglu",
+      "name": "Linden Wright",
+      "avatar_url": "https://avatars.githubusercontent.com/u/1638544?v=4",
+      "profile": "https://github.com/Kusmeroglu",
+      "contributions": ["code"]
     }
   ],
   "contributorsPerLine": 7

README.md

@@ -303,6 +303,7 @@ Thanks goes to these wonderful people ([emoji key](https://allcontributors.org/d
       <td align="center" valign="top" width="14.28%"><a href="https://github.com/Cellule"><img src="https://avatars.githubusercontent.com/u/4157103?v=4?s=100" width="100px;" alt="Michael &quot;Mike&quot; Ferris"/><br /><sub><b>Michael &quot;Mike&quot; Ferris</b></sub></a><br /><a href="https://github.com/fabien0102/openapi-codegen/commits?author=Cellule" title="Code">💻</a></td>
       <td align="center" valign="top" width="14.28%"><a href="https://github.com/rajzik"><img src="https://avatars.githubusercontent.com/u/10364836?v=4?s=100" width="100px;" alt="Jan Šilhan"/><br /><sub><b>Jan Šilhan</b></sub></a><br /><a href="https://github.com/fabien0102/openapi-codegen/issues?q=author%3Arajzik" title="Bug reports">🐛</a> <a href="https://github.com/fabien0102/openapi-codegen/commits?author=rajzik" title="Code">💻</a> <a href="https://github.com/fabien0102/openapi-codegen/commits?author=rajzik" title="Documentation">📖</a></td>
       <td align="center" valign="top" width="14.28%"><a href="https://github.com/dan-cooke"><img src="https://avatars.githubusercontent.com/u/22816887?v=4?s=100" width="100px;" alt="Daniel Cooke"/><br /><sub><b>Daniel Cooke</b></sub></a><br /><a href="https://github.com/fabien0102/openapi-codegen/issues?q=author%3Adan-cooke" title="Bug reports">🐛</a> <a href="https://github.com/fabien0102/openapi-codegen/commits?author=dan-cooke" title="Code">💻</a></td>
+      <td align="center" valign="top" width="14.28%"><a href="https://github.com/Kusmeroglu"><img src="https://avatars.githubusercontent.com/u/1638544?v=4?s=100" width="100px;" alt="Linden Wright"/><br /><sub><b>Linden Wright</b></sub></a><br /><a href="https://github.com/fabien0102/openapi-codegen/commits?author=Kusmeroglu" title="Code">💻</a></td>
     </tr>
   </tbody>
 </table>

plugins/typescript/src/core/schemaToTypeAliasDeclaration.test.ts

@@ -59,6 +59,15 @@ describe("schemaToTypeAliasDeclaration", () => {
     expect(printSchema(schema)).toBe("export type Test = number[];");
   });
 
+  it("should generate a string const", () => {
+    const schema: SchemaObject = {
+      const: "CONSTANT",
+      title: "Test",
+    };
+
+    expect(printSchema(schema)).toBe('export type Test = "CONSTANT";');
+  });
+
   it("should generate enums (strings)", () => {
     const schema: SchemaObject = {
       type: "string",

plugins/typescript/src/core/schemaToTypeAliasDeclaration.ts

@@ -189,6 +189,11 @@ export const getType = (
     schema.type = "array";
   }
 
+  // Handle string constant
+  if (schema.const && !schema.type) {
+    return f.createLiteralTypeNode(f.createStringLiteral(schema.const));
+  }
+
   switch (schema.type) {
     case "null":
       return f.createLiteralTypeNode(f.createNull());