process: add source-map support to stack traces

PR-URL: #29564
Reviewed-By: Anna Henningsen <anna@addaleax.net>
Reviewed-By: Benjamin Gruenbaum <benjamingr@gmail.com>
Reviewed-By: Matteo Collina <matteo.collina@gmail.com>
Reviewed-By: James M Snell <jasnell@gmail.com>

doc/api/cli.md

@@ -135,6 +135,15 @@ added: v6.0.0
 Enable FIPS-compliant crypto at startup. (Requires Node.js to be built with
 `./configure --openssl-fips`.)
 
+### `--enable-source-maps`
+<!-- YAML
+added: REPLACEME
+-->
+
+> Stability: 1 - Experimental
+
+Enable experimental Source Map V3 support for stack traces.
+
 ### `--es-module-specifier-resolution=mode`
 <!-- YAML
 added: v12.0.0
@@ -980,6 +989,7 @@ node --require "./a.js" --require "./b.js"
 Node.js options that are allowed are:
 <!-- node-options-node start -->
 * `--enable-fips`
+* `--enable-source-maps`
 * `--es-module-specifier-resolution`
 * `--experimental-exports`
 * `--experimental-loader`

lib/internal/bootstrap/pre_execution.js

@@ -21,6 +21,15 @@ function prepareMainThreadExecution(expandArgv1 = false) {
       setupCoverageHooks(process.env.NODE_V8_COVERAGE);
   }
 
+  // If source-map support has been enabled, we substitute in a new
+  // prepareStackTrace method, replacing the default in errors.js.
+  if (getOptionValue('--enable-source-maps')) {
+    const { prepareStackTrace } =
+      require('internal/source_map/source_map_cache');
+    const { setPrepareStackTraceCallback } = internalBinding('errors');
+    setPrepareStackTraceCallback(prepareStackTrace);
+  }
+
   setupDebugEnv();
 
   // Only main thread receives signals.
@@ -119,7 +128,8 @@ function setupCoverageHooks(dir) {
   const cwd = require('internal/process/execution').tryGetCwd();
   const { resolve } = require('path');
   const coverageDirectory = resolve(cwd, dir);
-  const { sourceMapCacheToObject } = require('internal/source_map');
+  const { sourceMapCacheToObject } =
+    require('internal/source_map/source_map_cache');
 
   if (process.features.inspector) {
     internalBinding('profiler').setCoverageDirectory(coverageDirectory);

lib/internal/modules/cjs/loader.js

@@ -31,7 +31,10 @@ const {
 } = primordials;
 
 const { NativeModule } = require('internal/bootstrap/loaders');
-const { maybeCacheSourceMap } = require('internal/source_map');
+const {
+  maybeCacheSourceMap,
+  rekeySourceMap
+} = require('internal/source_map/source_map_cache');
 const { pathToFileURL, fileURLToPath, URL } = require('internal/url');
 const { deprecate } = require('internal/util');
 const vm = require('vm');
@@ -51,6 +54,7 @@ const {
   loadNativeModule
 } = require('internal/modules/cjs/helpers');
 const { getOptionValue } = require('internal/options');
+const enableSourceMaps = getOptionValue('--enable-source-maps');
 const preserveSymlinks = getOptionValue('--preserve-symlinks');
 const preserveSymlinksMain = getOptionValue('--preserve-symlinks-main');
 const experimentalModules = getOptionValue('--experimental-modules');
@@ -707,7 +711,19 @@ Module._load = function(request, parent, isMain) {
 
   let threw = true;
   try {
-    module.load(filename);
+    // Intercept exceptions that occur during the first tick and rekey them
+    // on error instance rather than module instance (which will immediately be
+    // garbage collected).
+    if (enableSourceMaps) {
+      try {
+        module.load(filename);
+      } catch (err) {
+        rekeySourceMap(Module._cache[filename], err);
+        throw err; /* node-do-not-add-exception-line */
+      }
+    } else {
+      module.load(filename);
+    }
     threw = false;
   } finally {
     if (threw) {
@@ -846,9 +862,7 @@ Module.prototype.require = function(id) {
 var resolvedArgv;
 let hasPausedEntry = false;
 
-function wrapSafe(filename, content, cjsModuleInstance) {
-  maybeCacheSourceMap(filename, content, cjsModuleInstance);
-
+function wrapSafe(filename, content) {
   if (patched) {
     const wrapper = Module.wrap(content);
     return vm.runInThisContext(wrapper, {
@@ -913,7 +927,8 @@ Module.prototype._compile = function(content, filename) {
     manifest.assertIntegrity(moduleURL, content);
   }
 
-  const compiledWrapper = wrapSafe(filename, content, this);
+  maybeCacheSourceMap(filename, content, this);
+  const compiledWrapper = wrapSafe(filename, content);
 
   var inspectorWrapper = null;
   if (getOptionValue('--inspect-brk') && process._eval == null) {

lib/internal/modules/esm/translators.js

@@ -31,7 +31,7 @@ const {
 } = require('internal/errors').codes;
 const readFileAsync = promisify(fs.readFile);
 const JsonParse = JSON.parse;
-const { maybeCacheSourceMap } = require('internal/source_map');
+const { maybeCacheSourceMap } = require('internal/source_map/source_map_cache');
 
 const debug = debuglog('esm');