feat(compartment-mapper): Support source map generation

packages/compartment-mapper/src/archive.js

@@ -302,6 +302,7 @@ const digestLocation = async (powers, moduleLocation, options) => {
     commonDependencies = undefined,
     importHook: exitModuleImportHook = undefined,
     policy = undefined,
+    sourceMapHook = undefined,
   } = options || {};
   const { read, computeSha512 } = unpackReadPowers(powers);
   const {
@@ -350,6 +351,7 @@ const digestLocation = async (powers, moduleLocation, options) => {
     entryCompartmentName,
     entryModuleSpecifier,
     exitModuleImportHook: consolidatedExitModuleImportHook,
+    sourceMapHook,
   });
   // Induce importHook to record all the necessary modules to import the given module specifier.
   const { compartment, attenuatorsCompartment } = link(compartmentMap, {

packages/compartment-mapper/src/bundle.js

@@ -167,6 +167,7 @@ function getBundlerKitForModule(module) {
  * @param {Set<string>} [options.tags]
  * @param {object} [options.commonDependencies]
  * @param {Array<string>} [options.searchSuffixes]
+ * @param {import('./types.js').SourceMapHook} [options.sourceMapHook]
  * @returns {Promise<string>}
  */
 export const makeBundle = async (read, moduleLocation, options) => {
@@ -176,6 +177,7 @@ export const makeBundle = async (read, moduleLocation, options) => {
     tags: tagsOption,
     searchSuffixes,
     commonDependencies,
+    sourceMapHook = undefined,
   } = options || {};
   const tags = new Set(tagsOption);
 
@@ -212,6 +214,7 @@ export const makeBundle = async (read, moduleLocation, options) => {
     searchSuffixes,
     entryCompartmentName,
     entryModuleSpecifier,
+    sourceMapHook,
   });
 
   // Induce importHook to record all the necessary modules to import the given module specifier.

packages/compartment-mapper/src/import-archive.js

@@ -12,6 +12,7 @@
 /** @typedef {import('./types.js').HashFn} HashFn */
 /** @typedef {import('./types.js').StaticModuleType} StaticModuleType */
 /** @typedef {import('./types.js').ComputeSourceLocationHook} ComputeSourceLocationHook */
+/** @typedef {import('./types.js').ComputeSourceMapLocationHook} ComputeSourceMapLocationHook */
 /** @typedef {import('./types.js').LoadArchiveOptions} LoadArchiveOptions */
 /** @typedef {import('./types.js').ExecuteOptions} ExecuteOptions */
 /** @typedef {import('./types.js').ImportHookMaker} ImportHookMaker */
@@ -77,6 +78,7 @@ const postponeErrorToExecute = errorMessage => {
  * @param {HashFn} [computeSha512]
  * @param {ComputeSourceLocationHook} [computeSourceLocation]
  * @param {ExitModuleImportHook} [exitModuleImportHook]
+ * @param {import('./types.js').ComputeSourceMapLocationHook} [computeSourceMapLocation]
  * @returns {ImportHookMaker}
  */
 const makeArchiveImportHookMaker = (
@@ -86,6 +88,7 @@ const makeArchiveImportHookMaker = (
   computeSha512 = undefined,
   computeSourceLocation = undefined,
   exitModuleImportHook = undefined,
+  computeSourceMapLocation = undefined,
 ) => {
   // per-assembly:
   /** @type {ImportHookMaker} */
@@ -190,12 +193,28 @@ const makeArchiveImportHookMaker = (
           sourceLocation;
       }
 
+      let sourceMapUrl;
+      if (
+        computeSourceMapLocation !== undefined &&
+        module.sha512 !== undefined
+      ) {
+        sourceMapUrl = computeSourceMapLocation({
+          compartment: packageLocation,
+          module: moduleSpecifier,
+          location: sourceLocation,
+          sha512: module.sha512,
+        });
+      }
+
       // eslint-disable-next-line no-await-in-loop
       const { record } = await parse(
         moduleBytes,
         moduleSpecifier,
         sourceLocation,
         packageLocation,
+        {
+          sourceMapUrl,
+        },
       );
       return { record, specifier: moduleSpecifier };
     };
@@ -240,6 +259,7 @@ const makeFeauxModuleExportsNamespace = Compartment => {
  * @param {ExitModuleImportHook} [options.importHook]
  * @param {CompartmentConstructor} [options.Compartment]
  * @param {ComputeSourceLocationHook} [options.computeSourceLocation]
+ * @param {ComputeSourceMapLocationHook} [options.computeSourceMapLocation]
  * @returns {Promise<Application>}
  */
 export const parseArchive = async (
@@ -251,6 +271,7 @@ export const parseArchive = async (
     computeSha512 = undefined,
     expectedSha512 = undefined,
     computeSourceLocation = undefined,
+    computeSourceMapLocation = undefined,
     Compartment = DefaultCompartment,
     modules = undefined,
     importHook: exitModuleImportHook = undefined,
@@ -319,6 +340,7 @@ export const parseArchive = async (
       computeSha512,
       computeSourceLocation,
       compartmentExitModuleImportHook,
+      computeSourceMapLocation,
     );
     // A weakness of the current Compartment design is that the `modules` map
     // must be given a module namespace object that passes a brand check.
@@ -366,6 +388,7 @@ export const parseArchive = async (
       computeSha512,
       computeSourceLocation,
       compartmentExitModuleImportHook,
+      computeSourceMapLocation,
     );
     const { compartment, pendingJobsPromise } = link(compartmentMap, {
       makeImportHook,
@@ -398,13 +421,19 @@ export const loadArchive = async (
   options = {},
 ) => {
   const { read, computeSha512 } = unpackReadPowers(readPowers);
-  const { expectedSha512, computeSourceLocation, modules } = options;
+  const {
+    expectedSha512,
+    computeSourceLocation,
+    modules,
+    computeSourceMapLocation,
+  } = options;
   const archiveBytes = await read(archiveLocation);
   return parseArchive(archiveBytes, archiveLocation, {
     computeSha512,
     expectedSha512,
     computeSourceLocation,
     modules,
+    computeSourceMapLocation,
   });
 };
 

packages/compartment-mapper/src/import-hook.js

@@ -113,6 +113,7 @@ export const exitModuleImportHookMaker = ({
  * @param {string} options.entryCompartmentName
  * @param {string} options.entryModuleSpecifier
  * @param {ExitModuleImportHook} [options.exitModuleImportHook]
+ * @param {import('./types.js').SourceMapHook} [options.sourceMapHook]
  * @returns {ImportHookMaker}
  */
 export const makeImportHookMaker = (
@@ -124,6 +125,7 @@ export const makeImportHookMaker = (
     archiveOnly = false,
     computeSha512 = undefined,
     searchSuffixes = nodejsConventionSearchSuffixes,
+    sourceMapHook = undefined,
     entryCompartmentName,
     entryModuleSpecifier,
     exitModuleImportHook = undefined,
@@ -300,6 +302,8 @@ export const makeImportHookMaker = (
           _error => undefined,
         );
         if (moduleBytes !== undefined) {
+          /** @type {string | undefined} */
+          let sourceMap;
           // eslint-disable-next-line no-await-in-loop
           const envelope = await parse(
             moduleBytes,
@@ -308,6 +312,11 @@ export const makeImportHookMaker = (
             packageLocation,
             {
               readPowers,
+              sourceMapHook:
+                sourceMapHook &&
+                (nextSourceMapObject => {
+                  sourceMap = JSON.stringify(nextSourceMapObject);
+                }),
             },
           );
           const {
@@ -334,6 +343,15 @@ export const makeImportHookMaker = (
           let sha512;
           if (computeSha512 !== undefined) {
             sha512 = computeSha512(transformedBytes);
+
+            if (sourceMapHook !== undefined && sourceMap !== undefined) {
+              sourceMapHook(sourceMap, {
+                compartment: packageLocation,
+                module: candidateSpecifier,
+                location: moduleLocation,
+                sha512,
+              });
+            }
           }
 
           const packageRelativeLocation = moduleLocation.slice(

packages/compartment-mapper/src/link.js

@@ -91,13 +91,25 @@ const makeExtensionParser = (
       language = languageForExtension[extension] || extension;
     }
 
+    let sourceMap;
+
     if (has(moduleTransforms, language)) {
       try {
-        ({ bytes, parser: language } = await moduleTransforms[language](
+        ({
+          bytes,
+          parser: language,
+          sourceMap,
+        } = await moduleTransforms[language](
           bytes,
           specifier,
           location,
           packageLocation,
+          {
+            // At time of writing, sourceMap is always undefined, but keeping
+            // it here is more resilient if the surrounding if block becomes a
+            // loop for multi-step transforms.
+            sourceMap,
+          },
         ));
       } catch (err) {
         throw Error(
@@ -115,7 +127,10 @@ const makeExtensionParser = (
       );
     }
     const { parse } = parserForLanguage[language];
-    return parse(bytes, specifier, location, packageLocation, options);
+    return parse(bytes, specifier, location, packageLocation, {
+      sourceMap,
+      ...options,
+    });
   };
 };
 

packages/compartment-mapper/src/parse-archive-mjs.js

@@ -8,12 +8,18 @@ const textDecoder = new TextDecoder();
 /** @type {import('./types.js').ParseFn} */
 export const parseArchiveMjs = async (
   bytes,
-  _specifier,
-  _location,
-  _packageLocation,
+  specifier,
+  sourceUrl,
+  packageLocation,
+  options = {},
 ) => {
+  const { sourceMap, sourceMapHook } = options;
   const source = textDecoder.decode(bytes);
-  const record = new StaticModuleRecord(source);
+  const record = new StaticModuleRecord(source, {
+    sourceMap,
+    sourceMapUrl: sourceUrl,
+    sourceMapHook,
+  });
   const pre = textEncoder.encode(JSON.stringify(record));
   return {
     parser: 'pre-mjs-json',

packages/compartment-mapper/src/parse-mjs.js

@@ -8,11 +8,18 @@ const textDecoder = new TextDecoder();
 export const parseMjs = async (
   bytes,
   _specifier,
-  location,
+  sourceUrl,
   _packageLocation,
+  options = {},
 ) => {
+  const { sourceMap, sourceMapHook } = options;
   const source = textDecoder.decode(bytes);
-  const record = new StaticModuleRecord(source, location);
+  const record = new StaticModuleRecord(source, {
+    sourceUrl,
+    sourceMap,
+    sourceMapUrl: sourceUrl,
+    sourceMapHook,
+  });
   return {
     parser: 'mjs',
     bytes,

packages/compartment-mapper/src/parse-pre-mjs.js

@@ -10,11 +10,17 @@ export const parsePreMjs = async (
   _specifier,
   location,
   _packageLocation,
+  { sourceMapUrl },
 ) => {
   const text = textDecoder.decode(bytes);
   const record = parseLocatedJson(text, location);
-  // eslint-disable-next-line no-underscore-dangle
-  record.__syncModuleProgram__ += `//# sourceURL=${location}\n`;
+  if (sourceMapUrl) {
+    // eslint-disable-next-line no-underscore-dangle
+    record.__syncModuleProgram__ += `//# sourceMappingURL=${sourceMapUrl}\n`;
+  } else {
+    // eslint-disable-next-line no-underscore-dangle
+    record.__syncModuleProgram__ += `//# sourceURL=${location}\n`;
+  }
   return {
     parser: 'pre-mjs-json',
     bytes,

packages/compartment-mapper/src/types.js

@@ -194,24 +194,56 @@ export {};
  * @property {ShouldDeferError} shouldDeferError
  * @property {Record<string, Compartment>} compartments
  */
+
 /**
  * @callback ImportHookMaker
  * @param {ImportHookMakerOptions} options
  * @returns {ImportHook}
  */
 
+/**
+ * @typedef {object} SourceMapHookDetails
+ * @property {string} compartment
+ * @property {string} module
+ * @property {string} location
+ * @property {string} sha512
+ */
+
+/**
+ * @callback SourceMapHook
+ * @param {string} sourceMap
+ * @param {SourceMapHookDetails} details
+ */
+
+/**
+ * @typedef {object} ComputeSourceMapLocationDetails
+ * @property {string} compartment
+ * @property {string} module
+ * @property {string} location
+ * @property {string} sha512
+ */
+
+/**
+ * @callback ComputeSourceMapLocationHook
+ * @param {ComputeSourceMapLocationDetails} details
+ * @returns {string}
+ */
+
 /**
  * @callback ParseFn
  * @param {Uint8Array} bytes
  * @param {string} specifier
  * @param {string} location
  * @param {string} packageLocation
  * @param {object} [options]
+ * @param {string} [options.sourceMap]
+ * @param {string} [options.sourceMapUrl]
  * @param {ReadFn | ReadPowers} [options.readPowers]
  * @returns {Promise<{
  *   bytes: Uint8Array,
  *   parser: Language,
  *   record: FinalStaticModuleType,
+ *   sourceMap?: string,
  * }>}
  */
 
@@ -243,6 +275,7 @@ export {};
  * @property {Record<string, any>} [modules]
  * @property {typeof Compartment} [Compartment]
  * @property {ComputeSourceLocationHook} [computeSourceLocation]
+ * @property {ComputeSourceMapLocationHook} [computeSourceMapLocation]
  */
 
 /**
@@ -283,7 +316,9 @@ export {};
  * @param {string} specifier
  * @param {string} location
  * @param {string} packageLocation
- * @returns {Promise<{bytes: Uint8Array, parser: Language}>}
+ * @param {object} [options]
+ * @param {string} [options.sourceMap]
+ * @returns {Promise<{bytes: Uint8Array, parser: Language, sourceMap?: string}>}
  */
 
 // /////////////////////////////////////////////////////////////////////////////
@@ -335,6 +370,7 @@ export {};
  * @property {ExitModuleImportHook} [importHook]
  * @property {Array<string>} [searchSuffixes]
  * @property {Record<string, string>} [commonDependencies]
+ * @property {SourceMapHook} [sourceMapHook]
  */
 
 // /////////////////////////////////////////////////////////////////////////////