snapshot: insert argv[0] at argv[1] in setDeserializeMainFunction

Author: watilde

doc/api/v8.md

@@ -1362,7 +1362,7 @@ v8.startupSnapshot.setDeserializeMainFunction((shelf) => {
   // process.env and process.argv are refreshed during snapshot
   // deserialization.
   const lang = process.env.BOOK_LANG || 'en_US';
-  const book = process.argv[1];
+  const book = process.argv[2];
   const name = `${book}.${lang}.txt`;
   console.log(shelf.storage.get(name));
 }, shelf);

lib/internal/v8/startup_snapshot.js

@@ -106,10 +106,10 @@ function setDeserializeMainFunction(callback, data) {
       markBootstrapComplete,
     } = require('internal/process/pre_execution');
 
-    // This should be in sync with run_main_module.js until we make that
-    // a built-in main function.
-    // TODO(joyeecheung): make a copy of argv[0] and insert it as argv[1].
     prepareMainThreadExecution(false);
+    // Like SEA (FixupArgsForSEA), insert argv[0] at argv[1] so that user
+    // args begin at argv[2], consistent with run_main_module.js.
+    process.argv.splice(1, 0, process.argv[0]);
     markBootstrapComplete();
     callback(data);
   });

test/embedding/test-embedding-snapshot-as-file.js

@@ -43,7 +43,7 @@ spawnSyncAndAssert(
     stdout(output) {
       assert.deepStrictEqual(JSON.parse(output), {
         originalArgv: [embedtest, '__node_anonymous_main', ...buildSnapshotExecArgs],
-        currentArgv: [embedtest, ...runSnapshotExecArgs],
+        currentArgv: [embedtest, embedtest, ...runSnapshotExecArgs],
       });
       return true;
     },

test/embedding/test-embedding-snapshot-basic.js

@@ -43,7 +43,7 @@ spawnSyncAndAssert(
     stdout(output) {
       assert.deepStrictEqual(JSON.parse(output), {
         originalArgv: [embedtest, '__node_anonymous_main', ...buildSnapshotExecArgs],
-        currentArgv: [embedtest, ...runSnapshotExecArgs],
+        currentArgv: [embedtest, embedtest, ...runSnapshotExecArgs],
       });
       return true;
     },

test/embedding/test-embedding-snapshot-without-code-cache.js

@@ -43,7 +43,7 @@ spawnSyncAndAssert(
     stdout(output) {
       assert.deepStrictEqual(JSON.parse(output), {
         originalArgv: [embedtest, '__node_anonymous_main', ...buildSnapshotExecArgs],
-        currentArgv: [embedtest, ...runSnapshotExecArgs],
+        currentArgv: [embedtest, embedtest, ...runSnapshotExecArgs],
       });
       return true;
     },

test/fixtures/snapshot/typescript-main.js

@@ -9,8 +9,8 @@ const v8 = require('v8');
 const assert = require('assert');
 
 v8.startupSnapshot.setDeserializeMainFunction(( { ts }) => {
-  const input = process.argv[1];
-  const output = process.argv[2];
+  const input = process.argv[2];
+  const output = process.argv[3];
   console.error(`Compiling ${input} to ${output}`);
   assert(input);
   assert(output);

test/fixtures/snapshot/v8-startup-snapshot-api.js

@@ -48,7 +48,7 @@ v8.startupSnapshot.setDeserializeMainFunction((shelf) => {
   // process.env and process.argv are refreshed during snapshot
   // deserialization.
   const lang = process.env.BOOK_LANG || 'en_US';
-  const book = process.argv[1];
+  const book = process.argv[2];
   const name = `${book}.${lang}.txt`;
   console.error('Reading', name);
   console.log(shelf.storage.get(name).toString());

test/parallel/test-snapshot-argv1.js

@@ -49,6 +49,7 @@ require('v8').startupSnapshot.setDeserializeMainFunction(() => {
 
   const stdout = JSON.parse(child.stdout.toString().trim());
   assert.deepStrictEqual(stdout, [
+    process.execPath,
     process.execPath,
     'argv1',
     'argv2',