fix(compartment-mapper): Deterministic archives

packages/compartment-mapper/NEWS.md

@@ -20,6 +20,7 @@ User-visible changes to the compartment mapper:
   removal of the `ses/lockdown` light layering (there is no heavy layer to
   distinguish as the weight has shifted to the `@endo/static-module-record`
   package).
+* Archives are now deterministic.
 
 ## 0.2.4 (2021-03-30)
 

packages/compartment-mapper/src/archive.js

@@ -28,7 +28,7 @@ const parserForLanguage = {
  */
 const resolveLocation = (rel, abs) => new URL(rel, abs).toString();
 
-const { entries, fromEntries, values } = Object;
+const { keys, entries, fromEntries } = Object;
 
 /**
  * @param {Record<string, CompartmentDescriptor>} compartments
@@ -53,31 +53,39 @@ const renameCompartments = compartments => {
  */
 const translateCompartmentMap = (compartments, sources, renames) => {
   const result = {};
-  for (const [name, compartment] of entries(compartments)) {
+  for (const name of keys(compartments).sort()) {
+    const compartment = compartments[name];
     const { label } = compartment;
 
     // rename module compartments
     /** @type {Record<string, ModuleDescriptor>} */
     const modules = {};
-    for (const [name, module] of entries(compartment.modules || {})) {
-      const compartment = module.compartment
-        ? renames[module.compartment]
-        : undefined;
-      modules[name] = {
-        ...module,
-        compartment,
-      };
+    const compartmentModules = compartment.modules;
+    if (compartment.modules) {
+      for (const name of keys(compartmentModules).sort()) {
+        const module = compartmentModules[name];
+        const compartment = module.compartment
+          ? renames[module.compartment]
+          : undefined;
+        modules[name] = {
+          ...module,
+          compartment,
+        };
+      }
     }
 
     // integrate sources into modules
     const compartmentSources = sources[name];
-    for (const [name, source] of entries(compartmentSources || {})) {
-      const { location, parser, exit } = source;
-      modules[name] = {
-        location,
-        parser,
-        exit,
-      };
+    if (compartmentSources) {
+      for (const name of keys(compartmentSources).sort()) {
+        const source = compartmentSources[name];
+        const { location, parser, exit } = source;
+        modules[name] = {
+          location,
+          parser,
+          exit,
+        };
+      }
     }
 
     result[renames[name]] = {
@@ -111,9 +119,11 @@ const renameSources = (sources, renames) => {
  * @param {Sources} sources
  */
 const addSourcesToArchive = async (archive, sources) => {
-  for (const [compartment, modules] of entries(sources)) {
+  for (const compartment of keys(sources).sort()) {
+    const modules = sources[compartment];
     const compartmentLocation = resolveLocation(`${compartment}/`, 'file:///');
-    for (const { location, bytes } of values(modules)) {
+    for (const specifier of keys(modules).sort()) {
+      const { bytes, location } = modules[specifier];
       if (location !== undefined) {
         const moduleLocation = resolveLocation(location, compartmentLocation);
         const path = new URL(moduleLocation).pathname.slice(1); // elide initial "/"

packages/compartment-mapper/src/node-modules.js

@@ -26,7 +26,7 @@
 import { inferExports } from './infer-exports.js';
 import { parseLocatedJson } from './json.js';
 
-const { create, entries, keys, values } = Object;
+const { create, keys, values } = Object;
 
 const decoder = new TextDecoder();
 
@@ -222,7 +222,7 @@ const graphPackage = async (
   /** @type {Record<string, string>} */
   const dependencies = {};
   const children = [];
-  for (const name of keys(packageDescriptor.dependencies || {})) {
+  for (const name of keys(packageDescriptor.dependencies || {}).sort()) {
     children.push(
       // Mutual recursion ahead:
       // eslint-disable-next-line no-use-before-define
@@ -364,17 +364,17 @@ const translateGraph = (
   // The full map includes every exported module from every dependencey
   // package and is a complete list of every external module that the
   // corresponding compartment can import.
-  for (const [
-    packageLocation,
-    { label, dependencies, parsers, types },
-  ] of entries(graph)) {
+  for (const packageLocation of keys(graph).sort()) {
+    const { label, dependencies, parsers, types } = graph[packageLocation];
     /** @type {Record<string, ModuleDescriptor>} */
     const modules = {};
     /** @type {Record<string, ScopeDescriptor>} */
     const scopes = {};
-    for (const [dependencyName, packageLocation] of entries(dependencies)) {
+    for (const dependencyName of keys(dependencies).sort()) {
+      const packageLocation = dependencies[dependencyName];
       const { exports, explicit } = graph[packageLocation];
-      for (const [exportName, module] of entries(exports)) {
+      for (const exportName of keys(exports).sort()) {
+        const module = exports[exportName];
         modules[exportName] = {
           compartment: packageLocation,
           module,