2 files changed, 52 insertions, 0 deletions

diff --git a/cli/args/flags.rs b/cli/args/flags.rs
index 7922a3c19..513307e92 100644
--- a/cli/args/flags.rs
+++ b/cli/args/flags.rs
@@ -301,6 +301,7 @@ pub struct Flags {
   pub cached_only: bool,
   pub type_check_mode: TypeCheckMode,
   pub config_flag: ConfigFlag,
+  pub node_modules_dir: bool,
   pub coverage_dir: Option<String>,
   pub enable_testing_features: bool,
   pub ignore: Vec<PathBuf>,
@@ -1734,6 +1735,7 @@ fn compile_args(app: Command) -> Command {
     .arg(import_map_arg())
     .arg(no_remote_arg())
     .arg(no_npm_arg())
+    .arg(local_npm_arg())
     .arg(no_config_arg())
     .arg(config_arg())
     .arg(no_check_arg())
@@ -1749,6 +1751,7 @@ fn compile_args_without_check_args(app: Command) -> Command {
     .arg(import_map_arg())
     .arg(no_remote_arg())
     .arg(no_npm_arg())
+    .arg(local_npm_arg())
     .arg(config_arg())
     .arg(no_config_arg())
     .arg(reload_arg())
@@ -2153,6 +2156,12 @@ fn no_npm_arg<'a>() -> Arg<'a> {
     .help("Do not resolve npm modules")
 }
 
+fn local_npm_arg<'a>() -> Arg<'a> {
+  Arg::new("node-modules-dir")
+    .long("node-modules-dir")
+    .help("Creates a local node_modules folder")
+}
+
 fn unsafely_ignore_certificate_errors_arg<'a>() -> Arg<'a> {
   Arg::new("unsafely-ignore-certificate-errors")
     .long("unsafely-ignore-certificate-errors")
@@ -2799,6 +2808,7 @@ fn compile_args_parse(flags: &mut Flags, matches: &clap::ArgMatches) {
   import_map_arg_parse(flags, matches);
   no_remote_arg_parse(flags, matches);
   no_npm_arg_parse(flags, matches);
+  local_npm_args_parse(flags, matches);
   config_args_parse(flags, matches);
   no_check_arg_parse(flags, matches);
   check_arg_parse(flags, matches);
@@ -2814,6 +2824,7 @@ fn compile_args_without_no_check_parse(
   import_map_arg_parse(flags, matches);
   no_remote_arg_parse(flags, matches);
   no_npm_arg_parse(flags, matches);
+  local_npm_args_parse(flags, matches);
   config_args_parse(flags, matches);
   reload_arg_parse(flags, matches);
   lock_args_parse(flags, matches);
@@ -3061,6 +3072,12 @@ fn no_npm_arg_parse(flags: &mut Flags, matches: &clap::ArgMatches) {
   }
 }
 
+fn local_npm_args_parse(flags: &mut Flags, matches: &ArgMatches) {
+  if matches.is_present("node-modules-dir") {
+    flags.node_modules_dir = true;
+  }
+}
+
 fn inspect_arg_validate(val: &str) -> Result<(), String> {
   match val.parse::<SocketAddr>() {
     Ok(_) => Ok(()),
@@ -5035,6 +5052,22 @@ mod tests {
   }
 
   #[test]
+  fn local_npm() {
+    let r =
+      flags_from_vec(svec!["deno", "run", "--node-modules-dir", "script.ts"]);
+    assert_eq!(
+      r.unwrap(),
+      Flags {
+        subcommand: DenoSubcommand::Run(RunFlags {
+          script: "script.ts".to_string(),
+        }),
+        node_modules_dir: true,
+        ..Flags::default()
+      }
+    );
+  }
+
+  #[test]
   fn cached_only() {
     let r = flags_from_vec(svec!["deno", "run", "--cached-only", "script.ts"]);
     assert_eq!(
diff --git a/cli/args/mod.rs b/cli/args/mod.rs
index e4c0d8556..1e0c72b1c 100644
--- a/cli/args/mod.rs
+++ b/cli/args/mod.rs
@@ -42,6 +42,7 @@ use crate::emit::TsConfigWithIgnoredOptions;
 use crate::emit::TsTypeLib;
 use crate::file_fetcher::get_root_cert_store;
 use crate::file_fetcher::CacheSetting;
+use crate::fs_util;
 use crate::lockfile::Lockfile;
 use crate::version;
 
@@ -146,6 +147,24 @@ impl CliOptions {
     self.overrides.import_map_specifier = Some(path);
   }
 
+  /// Resolves the path to use for a local node_modules folder.
+  pub fn resolve_local_node_modules_folder(
+    &self,
+  ) -> Result<Option<PathBuf>, AnyError> {
+    let path = if !self.flags.node_modules_dir {
+      return Ok(None);
+    } else if let Some(config_path) = self
+      .maybe_config_file
+      .as_ref()
+      .and_then(|c| c.specifier.to_file_path().ok())
+    {
+      config_path.parent().unwrap().join("node_modules")
+    } else {
+      std::env::current_dir()?.join("node_modules")
+    };
+    Ok(Some(fs_util::canonicalize_path_maybe_not_exists(&path)?))
+  }
+
   pub fn resolve_root_cert_store(&self) -> Result<RootCertStore, AnyError> {
     get_root_cert_store(
       None,