Introduce a gpui::test macro

gpui_macros/src/lib.rs

@@ -0,0 +1,39 @@
+use std::mem;
+
+use proc_macro::TokenStream;
+use quote::{format_ident, quote};
+use syn::{parse_macro_input, ItemFn};
+
+#[proc_macro_attribute]
+pub fn test(args: TokenStream, function: TokenStream) -> TokenStream {
+    assert!(args.is_empty());
+
+    let mut inner_fn = parse_macro_input!(function as ItemFn);
+    let inner_fn_name = format_ident!("_{}", inner_fn.sig.ident);
+    let outer_fn_name = mem::replace(&mut inner_fn.sig.ident, inner_fn_name.clone());
+    let outer_fn = if inner_fn.sig.asyncness.is_some() {
+        quote! {
+            #[test]
+            fn #outer_fn_name() {
+                #inner_fn
+
+                gpui::App::test_async((), move |ctx| async {
+                    #inner_fn_name(ctx).await;
+                });
+            }
+        }
+    } else {
+        quote! {
+            #[test]
+            fn #outer_fn_name() {
+                #inner_fn
+
+                gpui::App::test((), |ctx| {
+                    #inner_fn_name(ctx);
+                });
+            }
+        }
+    };
+
+    TokenStream::from(outer_fn)
+}