feat: add preserve line breaks tag

Ticket: DX-2385

Author: starfy84

packages/openapi-generator/README.md

@@ -472,6 +472,9 @@ These are some tags that you can use in your schema JSDocs are custom to this ge
   will have `x-internal: true` for schemas with the `@private` tag.
 - `@deprecated` allows to mark any field in any schema as deprecated. The final spec
   will include `deprecated: true` in the final specificaiton.
+- `@preserveLineBreaks` preserves line breaks in descriptions. By default, multiline
+  descriptions are collapsed into a single line. Use this tag when you need to preserve
+  formatting, such as for markdown lists or structured text.
 
 ```typescript
 import * as t from 'io-ts';
@@ -482,5 +485,15 @@ const Schema = t.type({
   /** @deprecated */
   deprecatedField: t.string,
   publicNonDeprecatedField: t.string,
+  /**
+   * @preserveLineBreaks
+   * This description spans multiple lines
+   * and will preserve its line breaks.
+   *
+   * Available options:
+   * - `option1` - First option
+   * - `option2` - Second option
+   */
+  fieldWithFormattedDescription: t.string,
 });
 ```

packages/openapi-generator/src/comments.ts

@@ -40,7 +40,17 @@ export function leadingComment(
     commentString = commentString + endingSubstring;
   }
 
-  const parsedComment = parseComment(commentString, { spacing: 'preserve' });
+  const shouldPreserveLineBreaks = commentString.includes('@preserveLineBreaks');
+  if (shouldPreserveLineBreaks) {
+    // This handles both inline and separate line cases
+    commentString = commentString.replace(/^\s*\*\s*@preserveLineBreaks\s*$/gm, '');
+    commentString = commentString.replace(/@preserveLineBreaks\s*/g, '');
+  }
+
+  const parsedComment = parseComment(
+    commentString,
+    shouldPreserveLineBreaks ? { spacing: 'preserve' } : undefined,
+  );
 
   for (const block of parsedComment) {
     block.description = block.description.trim();

packages/openapi-generator/test/openapi/comments.test.ts

@@ -1658,7 +1658,7 @@ testCase(
   },
 );
 
-const ROUTE_WITH_MARKDOWN_LIST = `
+const ROUTE_WITH_MARKDOWN_LIST_AND_PRESERVE_LINE_BREAKS = `
 import * as t from 'io-ts';
 import * as h from '@api-ts/io-ts-http';
 
@@ -1674,6 +1674,7 @@ export const route = h.httpRoute({
   request: h.httpRequest({
     query: {
       /**
+       * @preserveLineBreaks
        * The permissions granted by this access token.
        *
        * - \`all\` - Access all actions in the test environment.
@@ -1688,46 +1689,127 @@ export const route = h.httpRoute({
 });
 `;
 
-testCase('route with markdown list in comment', ROUTE_WITH_MARKDOWN_LIST, {
-  openapi: '3.0.3',
-  info: {
-    title: 'Test',
-    version: '1.0.0',
-  },
-  paths: {
-    '/list': {
-      get: {
-        summary: 'A route with a list in the comment',
-        operationId: 'api.v1.list',
-        tags: ['Test Routes'],
-        parameters: [
-          {
-            name: 'permissions',
-            in: 'query',
-            required: true,
-            schema: {
-              type: 'string',
+testCase(
+  'route with markdown list in comment and @preserveLineBreaks tag',
+  ROUTE_WITH_MARKDOWN_LIST_AND_PRESERVE_LINE_BREAKS,
+  {
+    openapi: '3.0.3',
+    info: {
+      title: 'Test',
+      version: '1.0.0',
+    },
+    paths: {
+      '/list': {
+        get: {
+          summary: 'A route with a list in the comment',
+          operationId: 'api.v1.list',
+          tags: ['Test Routes'],
+          parameters: [
+            {
+              name: 'permissions',
+              in: 'query',
+              required: true,
+              schema: {
+                type: 'string',
+              },
+              description:
+                'The permissions granted by this access token.\n\n- `all` - Access all actions in the test environment.\n- `crypto_compare` - Call CryptoCompare API.',
             },
-            description:
-              'The permissions granted by this access token.\n\n- `all` - Access all actions in the test environment.\n- `crypto_compare` - Call CryptoCompare API.',
-          },
-        ],
-        responses: {
-          200: {
-            description: 'OK',
-            content: {
-              'application/json': {
-                schema: {
-                  type: 'string',
+          ],
+          responses: {
+            200: {
+              description: 'OK',
+              content: {
+                'application/json': {
+                  schema: {
+                    type: 'string',
+                  },
                 },
               },
             },
           },
         },
       },
     },
+    components: {
+      schemas: {},
+    },
   },
-  components: {
-    schemas: {},
+);
+
+const ROUTE_WITH_INLINE_PRESERVE_LINE_BREAKS = `
+import * as t from 'io-ts';
+import * as h from '@api-ts/io-ts-http';
+
+/**
+ * A route with inline preserveLineBreaks tag
+ *
+ * @operationId api.v1.inline
+ * @tag Test Routes
+ */
+export const route = h.httpRoute({
+  path: '/inline',
+  method: 'GET',
+  request: h.httpRequest({
+    query: {
+      /**
+       * @preserveLineBreaks This tag is inline with other text
+       * This is a long description that
+       * spans multiple lines in the source.
+       */
+      field1: t.string,
+    },
+  }),
+  response: {
+    200: t.string
   },
 });
+`;
+
+testCase(
+  'route with inline @preserveLineBreaks tag',
+  ROUTE_WITH_INLINE_PRESERVE_LINE_BREAKS,
+  {
+    openapi: '3.0.3',
+    info: {
+      title: 'Test',
+      version: '1.0.0',
+    },
+    paths: {
+      '/inline': {
+        get: {
+          summary: 'A route with inline preserveLineBreaks tag',
+          operationId: 'api.v1.inline',
+          tags: ['Test Routes'],
+          parameters: [
+            {
+              name: 'field1',
+              in: 'query',
+              required: true,
+              schema: {
+                type: 'string',
+              },
+              description:
+                'This tag is inline with other text\nThis is a long description that\nspans multiple lines in the source.',
+            },
+          ],
+          responses: {
+            200: {
+              description: 'OK',
+              content: {
+                'application/json': {
+                  schema: {
+                    type: 'string',
+                  },
+                },
+              },
+            },
+          },
+        },
+      },
+    },
+    components: {
+      schemas: {},
+    },
+  },
+);