module: reduce circular dependency of internal/modules/cjs/loader

Previously `internal/bootstrap/pre_execution.js` requires
`internal/modules/cjs/loader.js` which in turn requires
`internal/bootstrap/pre_execution.js`. This patch moves the
entry point execution logic out of `pre_execution.js` and
puts it into `internal/modules/run_main.js`. It also tests
that `Module.runMain` can be monkey-patched before further
deprecation/refactoring can be done.

Also added an internal assertion `hasLoadedAnyUserCJSModule`
for documentation purposes.

PR-URL: https://github.com/nodejs/node/pull/30349
Reviewed-By: Guy Bedford <guybedford@gmail.com>
Reviewed-By: James M Snell <jasnell@gmail.com>
Reviewed-By: Anna Henningsen <anna@addaleax.net>

1 files changed, 8 insertions, 0 deletions

diff --git a/test/fixtures/monkey-patch-run-main.js b/test/fixtures/monkey-patch-run-main.js
new file mode 100644
index 0000000000..949a5eca64
--- /dev/null
+++ b/test/fixtures/monkey-patch-run-main.js
@@ -0,0 +1,8 @@
+'use strict';
+
+const oldRunMain = require('module').runMain;
+
+require('module').runMain = function(...args) {
+  console.log('runMain is monkey patched!');
+  oldRunMain(...args);
+};