From 8c17ceb38fd9bc550f6e5fedb25ad80120396aba Mon Sep 17 00:00:00 2001 From: Joyee Cheung Date: Wed, 11 Jun 2025 11:33:16 +0200 Subject: [PATCH] module: allow cycles in require() in the CJS handling in ESM loader When --import is used, the ESM loader is used to handle even pure CJS entry points, and it can run into CJS module facades in the evaluating state when the parent CJS module is being evaluated. In this case it should be allowed, since the ESM <-> CJS cycles that are meant to be disallowed (for the time being) should already be detected before evaluation and wouldn't get here, and CJS <-> CJS cycles are fine. PR-URL: https://github.com/nodejs/node/pull/58598 Fixes: https://github.com/nodejs/node/issues/58515 Reviewed-By: Anna Henningsen Reviewed-By: Ethan Arrowood --- lib/internal/modules/esm/module_job.js | 11 ++++++++-- src/module_wrap.cc | 3 +-- .../test-import-preload-require-cycle.js | 20 +++++++++++++++++++ test/fixtures/import-require-cycle/a.js | 1 + test/fixtures/import-require-cycle/b.js | 1 + test/fixtures/import-require-cycle/c.js | 3 +++ .../fixtures/import-require-cycle/preload.mjs | 7 +++++++ 7 files changed, 42 insertions(+), 4 deletions(-) create mode 100644 test/es-module/test-import-preload-require-cycle.js create mode 100644 test/fixtures/import-require-cycle/a.js create mode 100644 test/fixtures/import-require-cycle/b.js create mode 100644 test/fixtures/import-require-cycle/c.js create mode 100644 test/fixtures/import-require-cycle/preload.mjs diff --git a/lib/internal/modules/esm/module_job.js b/lib/internal/modules/esm/module_job.js index 51aa863dd61..cac4f603229 100644 --- a/lib/internal/modules/esm/module_job.js +++ b/lib/internal/modules/esm/module_job.js @@ -26,6 +26,7 @@ const { ModuleWrap, kErrored, kEvaluated, + kEvaluating, kEvaluationPhase, kInstantiated, kUninstantiated, @@ -338,8 +339,14 @@ class ModuleJob extends ModuleJobBase { return { __proto__: null, module: this.module, namespace }; } throw this.module.getError(); - - } else if (status === kEvaluated) { + } else if (status === kEvaluating || status === kEvaluated) { + // kEvaluating can show up when this is being used to deal with CJS <-> CJS cycles. + // Allow it for now, since we only need to ban ESM <-> CJS cycles which would be + // detected earlier during the linking phase, though the CJS handling in the ESM + // loader won't be able to emit warnings on pending circular exports like what + // the CJS loader does. + // TODO(joyeecheung): remove the re-invented require() in the ESM loader and + // always handle CJS using the CJS loader to eliminate the quirks. return { __proto__: null, module: this.module, namespace: this.module.getNamespaceSync() }; } assert.fail(`Unexpected module status ${status}.`); diff --git a/src/module_wrap.cc b/src/module_wrap.cc index dd0f74c5580..2b81a4d5da6 100644 --- a/src/module_wrap.cc +++ b/src/module_wrap.cc @@ -783,11 +783,10 @@ void ModuleWrap::GetNamespaceSync(const FunctionCallbackInfo& args) { return realm->env()->ThrowError( "Cannot get namespace, module has not been instantiated"); case Module::Status::kInstantiated: + case Module::Status::kEvaluating: case Module::Status::kEvaluated: case Module::Status::kErrored: break; - case Module::Status::kEvaluating: - UNREACHABLE(); } if (module->IsGraphAsync()) { diff --git a/test/es-module/test-import-preload-require-cycle.js b/test/es-module/test-import-preload-require-cycle.js new file mode 100644 index 00000000000..c47b64ba584 --- /dev/null +++ b/test/es-module/test-import-preload-require-cycle.js @@ -0,0 +1,20 @@ +'use strict'; + +// This tests that --import preload does not break CJS entry points that contains +// require cycles. + +require('../common'); +const fixtures = require('../common/fixtures'); +const { spawnSyncAndAssert } = require('../common/child_process'); + +spawnSyncAndAssert( + process.execPath, + [ + '--import', + fixtures.fileURL('import-require-cycle/preload.mjs'), + fixtures.path('import-require-cycle/c.js'), + ], + { + stdout: /cycle equality true/, + } +); diff --git a/test/fixtures/import-require-cycle/a.js b/test/fixtures/import-require-cycle/a.js new file mode 100644 index 00000000000..595a5085cf5 --- /dev/null +++ b/test/fixtures/import-require-cycle/a.js @@ -0,0 +1 @@ +module.exports.b = require('./b.js'); diff --git a/test/fixtures/import-require-cycle/b.js b/test/fixtures/import-require-cycle/b.js new file mode 100644 index 00000000000..869be257319 --- /dev/null +++ b/test/fixtures/import-require-cycle/b.js @@ -0,0 +1 @@ +module.exports.a = require('./a.js'); diff --git a/test/fixtures/import-require-cycle/c.js b/test/fixtures/import-require-cycle/c.js new file mode 100644 index 00000000000..39099ad7607 --- /dev/null +++ b/test/fixtures/import-require-cycle/c.js @@ -0,0 +1,3 @@ +const obj = require('./b.js'); + +console.log('cycle equality', obj.a.b === obj); diff --git a/test/fixtures/import-require-cycle/preload.mjs b/test/fixtures/import-require-cycle/preload.mjs new file mode 100644 index 00000000000..81eed70009e --- /dev/null +++ b/test/fixtures/import-require-cycle/preload.mjs @@ -0,0 +1,7 @@ +import * as mod from "module"; + +mod.registerHooks({ + load(url, context, nextLoad) { + return nextLoad(url, context); + }, +});