fix(ruleset-bundler): virtualFs plugin incompatible with commonjs plugin

packages/ruleset-bundler/src/__tests__/index.jest.test.ts

@@ -0,0 +1,100 @@
+import { serveAssets } from '@stoplight/spectral-test-utils';
+import { fetch } from '@stoplight/spectral-runtime';
+import * as fs from 'fs';
+import { bundleRuleset } from '../index';
+import { IO } from '../types';
+import { node } from '../presets/node';
+import { browser } from '../presets/browser';
+import { commonjs } from '../plugins/commonjs';
+import { virtualFs } from '../plugins/virtualFs';
+import { runtime } from '../presets/runtime';
+
+jest.mock('fs');
+
+describe('Ruleset Bundler', () => {
+  let io: IO;
+
+  beforeEach(() => {
+    io = {
+      fs,
+      fetch,
+    };
+
+    serveAssets({
+      '/p/.spectral/my-fn.js': `module.exports = function f() { return [] };`,
+
+      '/p/spectral.js': `import myFn from './.spectral/my-fn.js';
+
+export default {
+  rules: {
+    rule: {
+       given: '$',
+       then: { function: myFn },
+    }
+  },
+};`,
+    });
+  });
+
+  it('given runtime target, should support commonjs', async () => {
+    const code = await bundleRuleset('/p/spectral.js', {
+      target: 'runtime',
+      plugins: [...runtime(io), commonjs()],
+    });
+
+    expect(code).toContain(`\tvar myFn = function f() { return [] };
+
+\tvar spectral = {
+\t  rules: {
+\t    rule: {
+\t       given: '$',
+\t       then: { function: myFn },
+\t    }
+\t  },
+\t};
+
+\treturn spectral;
+
+})();`);
+  });
+
+  it('given browser target, should support commonjs', async () => {
+    const code = await bundleRuleset('/p/spectral.js', {
+      target: 'browser',
+      plugins: [...browser(io), commonjs()],
+    });
+
+    expect(code).toContain(`var myFn = function f() { return [] };
+
+var spectral = {
+  rules: {
+    rule: {
+       given: '$',
+       then: { function: myFn },
+    }
+  },
+};
+
+export { spectral as default };`);
+  });
+
+  it('given node target, should support commonjs', async () => {
+    const code = await bundleRuleset('/p/spectral.js', {
+      target: 'node',
+      plugins: [...node(io), virtualFs(io), commonjs()],
+    });
+
+    expect(code).toContain(`var myFn = function f() { return [] };
+
+var spectral = {
+  rules: {
+    rule: {
+       given: '$',
+       then: { function: myFn },
+    }
+  },
+};
+
+export { spectral as default };`);
+  });
+});

packages/ruleset-bundler/src/plugins/virtualFs.ts

@@ -1,35 +1,48 @@
 import { dirname, parse, join, normalize, isAbsolute, isURL } from '@stoplight/path';
-import type { Plugin } from 'rollup';
+import type { Plugin, PluginContext } from 'rollup';
 import type { IO } from '../types';
 
-export const virtualFs = ({ fs }: IO): Plugin => ({
-  name: '@stoplight-spectral/virtual-fs',
-  resolveId(source, importer) {
-    const { protocol } = parse(source);
-
-    if (protocol === 'http' || protocol === 'https') {
-      return null;
-    }
-
-    if (protocol !== 'file' && !/^[./]/.test(source)) {
-      return null;
-    }
-
-    if (isAbsolute(source)) {
-      return normalize(source);
-    }
-
-    if (importer !== void 0) {
-      return join(dirname(importer), source);
-    }
-
-    return source;
-  },
-  load(id) {
-    if (!isURL(id)) {
-      return fs.promises.readFile(id, 'utf8');
-    }
-
-    return;
-  },
-});
+export const virtualFs = ({ fs }: IO): Plugin => {
+  const recognized = new WeakMap<PluginContext, string[]>();
+
+  return {
+    name: '@stoplight-spectral/virtual-fs',
+
+    resolveId(source, importer): string | null {
+      const { protocol } = parse(source);
+
+      if (protocol === 'http' || protocol === 'https') {
+        return null;
+      }
+
+      if (protocol !== 'file' && !/^[./]/.test(source)) {
+        return null;
+      }
+
+      let resolvedSource = source;
+
+      if (isAbsolute(source)) {
+        resolvedSource = normalize(source);
+      } else if (importer !== void 0) {
+        resolvedSource = join(dirname(importer), source);
+      }
+
+      let existingEntries = recognized.get(this);
+      if (existingEntries === void 0) {
+        existingEntries = [];
+        recognized.set(this, existingEntries);
+      }
+
+      existingEntries.push(resolvedSource);
+
+      return resolvedSource;
+    },
+    load(id): Promise<string> | undefined {
+      if (!isURL(id) && recognized.get(this)?.includes(id) === true) {
+        return fs.promises.readFile(id, 'utf8');
+      }
+
+      return;
+    },
+  };
+};