Avoid error when repeatedly clearing cache (#51)

Also avoid failing to clear the cache when it contains non-directories
(e.g., I had a `.DS_Store` after looking at it in Finder).

crates/puffin-cli/src/commands/clean.rs

@@ -1,6 +1,6 @@
 use std::path::Path;
 
-use anyhow::Result;
+use anyhow::{Context, Result};
 use tracing::info;
 
 use crate::commands::ExitStatus;
@@ -11,7 +11,32 @@ pub(crate) async fn clean(cache: Option<&Path>) -> Result<ExitStatus> {
         return Err(anyhow::anyhow!("No cache found"));
     };
 
+    if !cache.exists() {
+        return Ok(ExitStatus::Success);
+    }
+
     info!("Clearing cache at {}", cache.display());
-    cacache::clear(cache).await?;
+
+    for entry in cache
+        .read_dir()
+        .with_context(|| {
+            format!(
+                "Failed to read directory contents while clearing {}",
+                cache.display()
+            )
+        })?
+        .flatten()
+    {
+        if entry.file_type()?.is_dir() {
+            tokio::fs::remove_dir_all(entry.path())
+                .await
+                .with_context(|| format!("Failed to clear cache at {}", cache.display()))?;
+        } else {
+            tokio::fs::remove_file(entry.path())
+                .await
+                .with_context(|| format!("Failed to clear cache at {}", cache.display()))?;
+        }
+    }
+
     Ok(ExitStatus::Success)
 }