feat(openapi-generator): support Identifier type in route expressions

Add support for passing variables directly to apiSpec() without
requiring object literal syntax with spread operator.

Previously, this would fail:

```typescript
export const MyApiSpec = apiSpec(myApiSpecProps);
```

And required this workaround:

```typescript
export const MyApiSpec = apiSpec({
  ...myApiSpecProps
});
```

This change resolves identifiers when passed directly to apiSpec(),
handling both nested and imported identifiers.

Closes Ticket: DX-1604

Author: ericcrosson-bitgo

packages/openapi-generator/src/apiSpec.ts

@@ -15,6 +15,16 @@ export function parseApiSpec(
   sourceFile: SourceFile,
   expr: swc.Expression,
 ): E.Either<string, Route[]> {
+  // If apiSpec is passed an identifier (variable), first resolve it to its actual value
+  if (expr.type === 'Identifier') {
+    const resolvedE = resolveLiteralOrIdentifier(project, sourceFile, expr);
+    if (E.isLeft(resolvedE)) {
+      return resolvedE;
+    }
+    const [newSourceFile, resolvedExpr] = resolvedE.right;
+    return parseApiSpec(project, newSourceFile, resolvedExpr);
+  }
+
   if (expr.type !== 'ObjectExpression') {
     return errorLeft(`unimplemented route expression type ${expr.type}`);
   }

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

@@ -0,0 +1,204 @@
+import * as E from 'fp-ts/lib/Either';
+import assert from 'node:assert/strict';
+import test from 'node:test';
+import type { NestedDirectoryJSON } from 'memfs';
+
+import { TestProject } from './testProject';
+import { parseApiSpec, type Route } from '../src';
+import { MOCK_NODE_MODULES_DIR } from './externalModules';
+import { stripStacktraceOfErrors } from '../src/error';
+
+async function testCase(
+  description: string,
+  files: NestedDirectoryJSON,
+  entryPoint: string,
+  expected: Record<string, Route[]>,
+  expectedErrors: string[] = [],
+) {
+  test(description, async () => {
+    const project = new TestProject({ ...files, ...MOCK_NODE_MODULES_DIR });
+
+    await project.parseEntryPoint(entryPoint);
+    const sourceFile = project.get(entryPoint);
+    if (sourceFile === undefined) {
+      throw new Error(`could not find source file ${entryPoint}`);
+    }
+
+    const actual: Record<string, Route[]> = {};
+    const errors: string[] = [];
+    for (const symbol of sourceFile.symbols.declarations) {
+      if (symbol.init !== undefined) {
+        if (symbol.init.type !== 'CallExpression') {
+          continue;
+        } else if (
+          symbol.init.callee.type !== 'MemberExpression' ||
+          symbol.init.callee.property.type !== 'Identifier' ||
+          symbol.init.callee.property.value !== 'apiSpec'
+        ) {
+          continue;
+        } else if (symbol.init.arguments.length !== 1) {
+          continue;
+        }
+        const arg = symbol.init.arguments[0]!;
+        // Note: This test should handle identifiers, but currently fails
+        const result = parseApiSpec(project, sourceFile, arg.expression);
+        if (E.isLeft(result)) {
+          errors.push(result.left);
+        } else {
+          actual[symbol.name] = result.right;
+        }
+      }
+    }
+
+    assert.deepEqual(stripStacktraceOfErrors(errors), expectedErrors);
+    assert.deepEqual(actual, expected);
+  });
+}
+
+const IDENTIFIER_API_SPEC = {
+  '/index.ts': `
+    import * as t from 'io-ts';
+    import * as h from '@api-ts/io-ts-http';
+
+    const myApiSpecProps = {
+      'api.test': {
+        get: h.httpRoute({
+          path: '/test',
+          method: 'GET',
+          request: h.httpRequest({}),
+          response: {
+            200: t.string,
+          },
+        })
+      }
+    };
+
+    // This fails due to Identifier type not being handled
+    export const test = h.apiSpec(myApiSpecProps);`,
+};
+
+testCase(
+  'identifier api spec',
+  IDENTIFIER_API_SPEC,
+  '/index.ts',
+  {
+    test: [
+      {
+        path: '/test',
+        method: 'GET',
+        parameters: [],
+        response: { 200: { type: 'string', primitive: true } },
+      },
+    ],
+  },
+  [],
+);
+
+const WORKAROUND_API_SPEC = {
+  '/index.ts': `
+    import * as t from 'io-ts';
+    import * as h from '@api-ts/io-ts-http';
+
+    const myApiSpecProps = {
+      'api.test': {
+        get: h.httpRoute({
+          path: '/test',
+          method: 'GET',
+          request: h.httpRequest({}),
+          response: {
+            200: t.string,
+          },
+        })
+      }
+    };
+
+    // This works with the workaround
+    export const test = h.apiSpec({
+      ...myApiSpecProps
+    });`,
+};
+
+testCase('workaround api spec', WORKAROUND_API_SPEC, '/index.ts', {
+  test: [
+    {
+      path: '/test',
+      method: 'GET',
+      parameters: [],
+      response: { 200: { type: 'string', primitive: true } },
+    },
+  ],
+});
+
+const NESTED_IDENTIFIER_API_SPEC = {
+  '/index.ts': `
+    import * as t from 'io-ts';
+    import * as h from '@api-ts/io-ts-http';
+
+    const routeSpec = h.httpRoute({
+      path: '/test',
+      method: 'GET',
+      request: h.httpRequest({}),
+      response: {
+        200: t.string,
+      },
+    });
+
+    const routeObj = {
+      get: routeSpec
+    };
+
+    const myApiSpecProps = {
+      'api.test': routeObj
+    };
+
+    // This should now work with our fix
+    export const test = h.apiSpec(myApiSpecProps);`,
+};
+
+testCase('nested identifier api spec', NESTED_IDENTIFIER_API_SPEC, '/index.ts', {
+  test: [
+    {
+      path: '/test',
+      method: 'GET',
+      parameters: [],
+      response: { 200: { type: 'string', primitive: true } },
+    },
+  ],
+});
+
+const IMPORTED_IDENTIFIER_API_SPEC = {
+  '/routes.ts': `
+    import * as t from 'io-ts';
+    import * as h from '@api-ts/io-ts-http';
+
+    export const apiRoutes = {
+      'api.test': {
+        get: h.httpRoute({
+          path: '/test',
+          method: 'GET',
+          request: h.httpRequest({}),
+          response: {
+            200: t.string,
+          },
+        })
+      }
+    };
+  `,
+  '/index.ts': `
+    import * as h from '@api-ts/io-ts-http';
+    import { apiRoutes } from './routes';
+
+    // This should now work with our fix
+    export const test = h.apiSpec(apiRoutes);`,
+};
+
+testCase('imported identifier api spec', IMPORTED_IDENTIFIER_API_SPEC, '/index.ts', {
+  test: [
+    {
+      path: '/test',
+      method: 'GET',
+      parameters: [],
+      response: { 200: { type: 'string', primitive: true } },
+    },
+  ],
+});