1 files changed, 42 insertions, 3 deletions
diff --git a/lib/internal/bootstrap/node.js b/lib/internal/bootstrap/node.js
index 284778becf..128725a532 100644
--- a/lib/internal/bootstrap/node.js
+++ b/lib/internal/bootstrap/node.js
@@ -671,9 +671,45 @@
     const test = Function.call.bind(RegExp.prototype.test);
 
     const {
-      allowedV8EnvironmentFlags,
-      allowedNodeEnvironmentFlags
-    } = process.binding('config');
+      getOptions,
+      types: { kV8Option },
+      envSettings: { kAllowedInEnvironment }
+    } = internalBinding('options');
+    const { options, aliases } = getOptions();
+
+    const allowedV8EnvironmentFlags = [];
+    const allowedNodeEnvironmentFlags = [];
+    for (const [name, info] of options) {
+      if (info.envVarSettings === kAllowedInEnvironment) {
+        if (info.type === kV8Option) {
+          allowedV8EnvironmentFlags.push(name);
+        } else {
+          allowedNodeEnvironmentFlags.push(name);
+        }
+      }
+    }
+
+    for (const [ from, expansion ] of aliases) {
+      let isAccepted = true;
+      for (const to of expansion) {
+        if (!to.startsWith('-')) continue;
+        const recursiveExpansion = aliases.get(to);
+        if (recursiveExpansion) {
+          expansion.push(...recursiveExpansion);
+          continue;
+        }
+        isAccepted = options.get(to).envVarSettings === kAllowedInEnvironment;
+        if (!isAccepted) break;
+      }
+      if (isAccepted) {
+        let canonical = from;
+        if (canonical.endsWith('='))
+          canonical = canonical.substr(0, canonical.length - 1);
+        if (canonical.endsWith(' <arg>'))
+          canonical = canonical.substr(0, canonical.length - 4);
+        allowedNodeEnvironmentFlags.push(canonical);
+      }
+    }
 
     const trimLeadingDashes = (flag) => replace(flag, leadingDashesRegex, '');
 
@@ -711,6 +747,9 @@
         // permutations of a flag, including present/missing leading
         // dash(es) and/or underscores-for-dashes in the case of V8-specific
         // flags.  Strips any values after `=`, inclusive.
+        // TODO(addaleax): It might be more flexible to run the option parser
+        // on a dummy option set and see whether it rejects the argument or
+        // not.
         if (typeof key === 'string') {
           key = replace(key, trailingValuesRegex, '');
           if (test(leadingDashesRegex, key)) {