Avoid re-fetching Unicode data

If the unicode-downloads folder already exists, we likely just fetched the data,
so don't make any further network requests. Unicode versions are released rarely
enough that this doesn't matter much in practice.

1 files changed, 8 insertions, 3 deletions

diff --git a/src/tools/unicode-table-generator/src/unicode_download.rs b/src/tools/unicode-table-generator/src/unicode_download.rs
index 3f6de9ea3bb..fa57f650ac0 100644
--- a/src/tools/unicode-table-generator/src/unicode_download.rs
+++ b/src/tools/unicode-table-generator/src/unicode_download.rs
@@ -11,10 +11,15 @@ static RESOURCES: &[&str] =
 
 pub fn fetch_latest() {
     let directory = Path::new(UNICODE_DIRECTORY);
+    if directory.exists() {
+        eprintln!(
+            "Not refetching unicode data, already exists, please delete {:?} to regenerate",
+            directory
+        );
+        return;
+    }
     if let Err(e) = std::fs::create_dir_all(directory) {
-        if e.kind() != std::io::ErrorKind::AlreadyExists {
-            panic!("Failed to create {:?}: {}", UNICODE_DIRECTORY, e);
-        }
+        panic!("Failed to create {:?}: {}", UNICODE_DIRECTORY, e);
     }
     let output = Command::new("curl").arg(URL_PREFIX.to_owned() + README).output().unwrap();
     if !output.status.success() {