feat: extract package implementation (#1647)

* feat: extract registry implementation

* feat: tinymist package

* fix: guard

* fix: guard 2

* feat: no specifier

* fix: temp_dir_in impl

* fix: impls

* feat: UniversePack::new

* feat: clone into memory

* feat: implement some pack for testing

* build: update cargo.lock

* feat: fit for web

* fix: guard

crates/tinymist-std/src/fs/paths.rs

@@ -220,6 +220,23 @@ pub fn write_atomic<P: AsRef<Path>, C: AsRef<[u8]>>(path: P, contents: C) -> Res
     Ok(())
 }
 
+/// Creates a temporary directory in the given path and calls the given
+/// function.
+///
+/// The temporary directory is automatically destroyed after the function
+/// returns, even if it panics.
+///
+/// Note: it may leak if the process is killed.
+pub fn temp_dir_in<P: AsRef<Path>, T>(path: P, f: impl FnOnce(&Path) -> Result<T>) -> Result<T> {
+    let path = path.as_ref();
+
+    std::fs::create_dir_all(path)
+        .with_context(|| format!("failed to create directory for tmpdir `{}`", path.display()))?;
+
+    let tmp = TempFileBuilder::new().tempdir_in(path)?;
+    f(tmp.path())
+}
+
 /// Equivalent to [`write()`], but does not write anything if the file contents
 /// are identical to the given contents.
 pub fn write_if_changed<P: AsRef<Path>, C: AsRef<[u8]>>(path: P, contents: C) -> Result<()> {