From 226a373c497cc3439e032332fefaffa75211afbd Mon Sep 17 00:00:00 2001
From: =?UTF-8?q?Bartek=20Iwa=C5=84czuk?= <biwanczuk@gmail.com>
Date: Sat, 13 May 2023 21:42:34 +0200
Subject: [PATCH] fix(lsp): increase default max heap size to 3Gb (#19115)

---
 cli/main.rs           |  8 +++++++-
 cli/standalone/mod.rs |  2 +-
 cli/util/v8.rs        | 15 ++++++++++++---
 3 files changed, 20 insertions(+), 5 deletions(-)

diff --git a/cli/main.rs b/cli/main.rs
index 03e7cf41e7..75425cf105 100644
--- a/cli/main.rs
+++ b/cli/main.rs
@@ -281,7 +281,13 @@ pub fn main() {
       Err(err) => unwrap_or_exit(Err(AnyError::from(err))),
     };
 
-    init_v8_flags(&flags.v8_flags, get_v8_flags_from_env());
+    let default_v8_flags = match flags.subcommand {
+      // Using same default as VSCode:
+      // https://github.com/microsoft/vscode/blob/48d4ba271686e8072fc6674137415bc80d936bc7/extensions/typescript-language-features/src/configuration/configuration.ts#L213-L214
+      DenoSubcommand::Lsp => vec!["--max-old-space-size=3072".to_string()],
+      _ => vec![],
+    };
+    init_v8_flags(&default_v8_flags, &flags.v8_flags, get_v8_flags_from_env());
 
     util::logger::init(flags.log_level);
 
diff --git a/cli/standalone/mod.rs b/cli/standalone/mod.rs
index db2743be86..eb5cf5d828 100644
--- a/cli/standalone/mod.rs
+++ b/cli/standalone/mod.rs
@@ -430,7 +430,7 @@ pub async fn run(
     },
   );
 
-  v8_set_flags(construct_v8_flags(&metadata.v8_flags, vec![]));
+  v8_set_flags(construct_v8_flags(&[], &metadata.v8_flags, vec![]));
 
   let mut worker = worker_factory
     .create_main_worker(main_module.clone(), permissions)
diff --git a/cli/util/v8.rs b/cli/util/v8.rs
index 6afaf285e3..93a2ef83f7 100644
--- a/cli/util/v8.rs
+++ b/cli/util/v8.rs
@@ -10,17 +10,26 @@ pub fn get_v8_flags_from_env() -> Vec<String> {
 
 #[inline(always)]
 pub fn construct_v8_flags(
+  default_v8_flags: &[String],
   v8_flags: &[String],
   env_v8_flags: Vec<String>,
 ) -> Vec<String> {
   std::iter::once("UNUSED_BUT_NECESSARY_ARG0".to_owned())
+    .chain(default_v8_flags.iter().cloned())
     .chain(env_v8_flags.into_iter())
     .chain(v8_flags.iter().cloned())
     .collect::<Vec<_>>()
 }
 
-pub fn init_v8_flags(v8_flags: &[String], env_v8_flags: Vec<String>) {
-  if v8_flags.is_empty() && env_v8_flags.is_empty() {
+pub fn init_v8_flags(
+  default_v8_flags: &[String],
+  v8_flags: &[String],
+  env_v8_flags: Vec<String>,
+) {
+  if default_v8_flags.is_empty()
+    && v8_flags.is_empty()
+    && env_v8_flags.is_empty()
+  {
     return;
   }
 
@@ -29,7 +38,7 @@ pub fn init_v8_flags(v8_flags: &[String], env_v8_flags: Vec<String>) {
     .chain(v8_flags)
     .any(|flag| flag == "-help" || flag == "--help");
   // Keep in sync with `standalone.rs`.
-  let v8_flags = construct_v8_flags(v8_flags, env_v8_flags);
+  let v8_flags = construct_v8_flags(default_v8_flags, v8_flags, env_v8_flags);
   let unrecognized_v8_flags = deno_core::v8_set_flags(v8_flags)
     .into_iter()
     .skip(1)