perf(jsr): fast check cache and lazy fast check graph (#22485)

1 files changed, 7 insertions, 0 deletions

diff --git a/tests/util/server/src/fs.rs b/tests/util/server/src/fs.rs
index 0e47a7503..d99572b06 100644
--- a/tests/util/server/src/fs.rs
+++ b/tests/util/server/src/fs.rs
@@ -4,6 +4,8 @@ use pretty_assertions::assert_eq;
 use std::borrow::Cow;
 use std::ffi::OsStr;
 use std::fs;
+use std::fs::OpenOptions;
+use std::io::Write;
 use std::path::Path;
 use std::path::PathBuf;
 use std::process::Command;
@@ -134,6 +136,11 @@ impl PathRef {
     fs::rename(self, self.join(to)).unwrap();
   }
 
+  pub fn append(&self, text: impl AsRef<str>) {
+    let mut file = OpenOptions::new().append(true).open(self).unwrap();
+    file.write_all(text.as_ref().as_bytes()).unwrap();
+  }
+
   pub fn write(&self, text: impl AsRef<str>) {
     fs::write(self, text.as_ref()).unwrap();
   }