Merge pull request #4767 from Agoric/mfig-xsnap-logging

Rework `xsnap/src/object-inspect.js`

packages/SwingSet/test/snapshots/test-xsnap-store.js.md

@@ -12,8 +12,8 @@ Generated by [AVA](https://avajs.dev).
 
 > after SES boot - sensitive to SES-shim, XS, and supervisor
 
-    'e71b8f4b7b749dea1a295da4b66c6b7bef8b2eb812bba5ccf0a3d91c408ce43f'
+    'e728d42dcfad5a32fbce4767ede358a833a52e3d4f3e6e998651280a947d576c'
 
 > after use of harden() - sensitive to SES-shim, XS, and supervisor
 
-    '7ddd8102ddb1f626ecf3833796d16abfd29cf74a8be3f55a1a13038092f73140'
+    '8ef12286ec4b89aad9679480c79f35e3198a7e6e6ad687b76f37fdf303599483'

packages/xsnap/lib/confined-object-inspect.js

@@ -0,0 +1,24 @@
+import objectInspectSources from '../dist/src-object-inspect.js';
+
+// Ensure the object inspector is confined.
+const c = new Compartment();
+harden(c.globalThis);
+
+// Transform the imported inspector module source string into an evaluable
+// string.  We could have played more games with bundlers to do something less
+// fragile, but even so, SES should fail-safe if this replacement doesn't match.
+//
+// The goal (presuming the file ends with a single export default statement):
+//   `...\n  export default harden(inspect0);`
+// becomes:
+//   `...\n  /* export default */ harden(inspect0);`
+// and we can evaluate it to obtain the completion value as the object inspector.
+const src = objectInspectSources.replace(
+  /(^|\s)(export\s+default)(\s+)/g,
+  '$1/* $2 */$3',
+);
+const objectInspect = c.evaluate(
+  `${src}\n//# sourceURL=xsnap/src/object-inspect.js\n`,
+);
+
+export default objectInspect;

packages/xsnap/lib/console-shim.js

@@ -1,6 +1,12 @@
 /* global globalThis, print */
 
-import inspect from './object-inspect.js';
+// Default implementation just stringifies.
+let inspect = String;
+
+// Allow the importer to override the inspect function.
+export const setObjectInspector = objectInspector => {
+  inspect = objectInspector;
+};
 
 const printAll = (...args) => {
   // Though xsnap doesn't have a whole console, it does have print().