fix(yarn): no longer error on pnp (#5009)

### Description

Fixes #4953

We had unintentionally dropped the PnP check in Go and reintroduced the
check in Rust. This PR simply removes this check and returns us to the
old unintentional behavior. I believe run should work as expected since
we execute all tasks via `yarn` which automatically does the right thing
with `.pnp.cjs`. (Also #4953 contains many reports of people using Yarn
PnP with turbo just fine)

This PR does not:
- Add support for PnP with prune. That check was never accidentally
dropped and I want to do a few more tests before enabling that.
- Fixup our examples to work correctly with Yarn PnP. All of the ones I
tried required adding some dependencies

Reviewer notes:
I apologize, but I ended up fixing all the clippy lints in the files I
touched and not just the ones introduced from the behavior change. This
resulted in the PR being larger than necessary.

### Testing Instructions

Existing unit tests around yarn/berry detection now pass without the a
`.yarnrc.yml` specifying `nodeLinker: node-modules`. Manual testing of
some test repos

Co-authored-by: Chris Olszewski <Chris Olszewski>

crates/turborepo-lib/src/package_manager/mod.rs

@@ -11,7 +11,6 @@ use anyhow::{anyhow, Result};
 use itertools::Itertools;
 use regex::Regex;
 use serde::{Deserialize, Serialize};
-use turbopath::AbsoluteSystemPathBuf;
 
 use crate::{
     commands::CommandBase,
@@ -166,9 +165,7 @@ impl PackageManager {
         // We don't surface errors for `read_package_manager` as we can fall back to
         // `detect_package_manager`
         if let Some(package_json) = pkg {
-            if let Ok(Some(package_manager)) =
-                Self::read_package_manager(&base.repo_root, package_json)
-            {
+            if let Ok(Some(package_manager)) = Self::read_package_manager(package_json) {
                 return Ok(package_manager);
             }
         }
@@ -177,10 +174,7 @@ impl PackageManager {
     }
 
     // Attempts to read the package manager from the package.json
-    fn read_package_manager(
-        repo_root: &AbsoluteSystemPathBuf,
-        pkg: &PackageJson,
-    ) -> Result<Option<Self>> {
+    fn read_package_manager(pkg: &PackageJson) -> Result<Option<Self>> {
         let Some(package_manager) = &pkg.package_manager else {
             return Ok(None)
         };
@@ -189,7 +183,7 @@ impl PackageManager {
         let version = version.parse()?;
         let manager = match manager {
             "npm" => Some(PackageManager::Npm),
-            "yarn" => Some(YarnDetector::detect_berry_or_yarn(repo_root, &version)?),
+            "yarn" => Some(YarnDetector::detect_berry_or_yarn(&version)?),
             "pnpm" => Some(PnpmDetector::detect_pnpm6_or_pnpm(&version)?),
             _ => None,
         };
@@ -246,9 +240,10 @@ mod tests {
     use std::{fs::File, path::Path};
 
     use tempfile::tempdir;
+    use turbopath::AbsoluteSystemPathBuf;
 
     use super::*;
-    use crate::{get_version, package_manager::yarn::YARN_RC, ui::UI, Args};
+    use crate::{get_version, ui::UI, Args};
 
     struct TestCase {
         name: String,
@@ -340,32 +335,26 @@ mod tests {
 
     #[test]
     fn test_read_package_manager() -> Result<()> {
-        let repo_root = tempdir()?;
-        let mut package_json = PackageJson::default();
-        let repo_root_path = AbsoluteSystemPathBuf::new(repo_root.path())?;
-
-        // Set up .yarnrc.yml file
-        let yarn_rc_path = repo_root.path().join(YARN_RC);
-        fs::write(&yarn_rc_path, "nodeLinker: node-modules")?;
-
-        package_json.package_manager = Some("npm@8.19.4".to_string());
-        let package_manager = PackageManager::read_package_manager(&repo_root_path, &package_json)?;
+        let mut package_json = PackageJson {
+            package_manager: Some("npm@8.19.4".to_string()),
+        };
+        let package_manager = PackageManager::read_package_manager(&package_json)?;
         assert_eq!(package_manager, Some(PackageManager::Npm));
 
         package_json.package_manager = Some("yarn@2.0.0".to_string());
-        let package_manager = PackageManager::read_package_manager(&repo_root_path, &package_json)?;
+        let package_manager = PackageManager::read_package_manager(&package_json)?;
         assert_eq!(package_manager, Some(PackageManager::Berry));
 
         package_json.package_manager = Some("yarn@1.9.0".to_string());
-        let package_manager = PackageManager::read_package_manager(&repo_root_path, &package_json)?;
+        let package_manager = PackageManager::read_package_manager(&package_json)?;
         assert_eq!(package_manager, Some(PackageManager::Yarn));
 
         package_json.package_manager = Some("pnpm@6.0.0".to_string());
-        let package_manager = PackageManager::read_package_manager(&repo_root_path, &package_json)?;
+        let package_manager = PackageManager::read_package_manager(&package_json)?;
         assert_eq!(package_manager, Some(PackageManager::Pnpm6));
 
         package_json.package_manager = Some("pnpm@7.2.0".to_string());
-        let package_manager = PackageManager::read_package_manager(&repo_root_path, &package_json)?;
+        let package_manager = PackageManager::read_package_manager(&package_json)?;
         assert_eq!(package_manager, Some(PackageManager::Pnpm));
 
         Ok(())
@@ -385,7 +374,7 @@ mod tests {
         let package_lock_json_path = repo_root.path().join(npm::LOCKFILE);
         File::create(&package_lock_json_path)?;
         let pnpm_lock_path = repo_root.path().join(pnpm::LOCKFILE);
-        File::create(&pnpm_lock_path)?;
+        File::create(pnpm_lock_path)?;
 
         let error = PackageManager::detect_package_manager(&base).unwrap_err();
         assert_eq!(

crates/turborepo-lib/src/package_manager/yarn.rs

@@ -1,21 +1,13 @@
-use std::{fs::File, process::Command};
+use std::process::Command;
 
-use anyhow::{anyhow, Context, Result};
+use anyhow::Result;
 use node_semver::{Range, Version};
-use serde::Deserialize;
 use turbopath::{AbsoluteSystemPathBuf, RelativeSystemPathBuf};
 use which::which;
 
 use crate::package_manager::PackageManager;
 
-#[derive(Debug, Deserialize)]
-struct YarnRC {
-    #[serde(rename = "nodeLinker")]
-    node_linker: Option<String>,
-}
-
 pub const LOCKFILE: &str = "yarn.lock";
-pub const YARN_RC: &str = ".yarnrc.yml";
 
 pub struct YarnDetector<'a> {
     repo_root: &'a AbsoluteSystemPathBuf,
@@ -46,34 +38,15 @@ impl<'a> YarnDetector<'a> {
         let yarn_binary = which("yarn")?;
         let output = Command::new(yarn_binary)
             .arg("--version")
-            .current_dir(&self.repo_root)
+            .current_dir(self.repo_root)
             .output()?;
         let yarn_version_output = String::from_utf8(output.stdout)?;
         Ok(yarn_version_output.trim().parse()?)
     }
 
-    fn is_nm_linker(repo_root: &AbsoluteSystemPathBuf) -> Result<bool> {
-        let yarnrc_path = repo_root.join_relative(RelativeSystemPathBuf::new(YARN_RC)?);
-        let yarnrc = File::open(yarnrc_path)?;
-        let yarnrc: YarnRC = serde_yaml::from_reader(&yarnrc)?;
-        Ok(yarnrc.node_linker.as_deref() == Some("node-modules"))
-    }
-
-    pub fn detect_berry_or_yarn(
-        repo_root: &AbsoluteSystemPathBuf,
-        version: &Version,
-    ) -> Result<PackageManager> {
+    pub fn detect_berry_or_yarn(version: &Version) -> Result<PackageManager> {
         let berry_constraint: Range = ">=2.0.0-0".parse()?;
         if berry_constraint.satisfies(version) {
-            let is_nm_linker = Self::is_nm_linker(repo_root)
-                .context("could not determine if yarn is using `nodeLinker: node-modules`")?;
-
-            if !is_nm_linker {
-                return Err(anyhow!(
-                    "only yarn v2/v3 with `nodeLinker: node-modules` is supported at this time"
-                ));
-            }
-
             Ok(PackageManager::Berry)
         } else {
             Ok(PackageManager::Yarn)
@@ -97,7 +70,7 @@ impl<'a> Iterator for YarnDetector<'a> {
         if yarn_lockfile.exists() {
             Some(
                 self.get_yarn_version()
-                    .and_then(|version| Self::detect_berry_or_yarn(self.repo_root, &version)),
+                    .and_then(|version| Self::detect_berry_or_yarn(&version)),
             )
         } else {
             None
@@ -107,7 +80,7 @@ impl<'a> Iterator for YarnDetector<'a> {
 
 #[cfg(test)]
 mod tests {
-    use std::{fs, fs::File};
+    use std::fs::File;
 
     use anyhow::Result;
     use tempfile::tempdir;
@@ -117,10 +90,7 @@ mod tests {
     use crate::{
         commands::CommandBase,
         get_version,
-        package_manager::{
-            yarn::{YarnDetector, YARN_RC},
-            PackageManager,
-        },
+        package_manager::{yarn::YarnDetector, PackageManager},
         ui::UI,
         Args,
     };
@@ -139,9 +109,6 @@ mod tests {
         let yarn_lock_path = repo_root.path().join(LOCKFILE);
         File::create(&yarn_lock_path)?;
 
-        let yarn_rc_path = repo_root.path().join(YARN_RC);
-        fs::write(&yarn_rc_path, "nodeLinker: node-modules")?;
-
         let absolute_repo_root = AbsoluteSystemPathBuf::new(base.repo_root)?;
         let mut detector = YarnDetector::new(&absolute_repo_root);
         detector.set_version_override("1.22.10".parse()?);