fix(dev): show first compilation error when build fails

.changeset/thin-knives-try.md

@@ -0,0 +1,5 @@
+---
+"@remix-run/dev": patch
+---
+
+show first compilation error instead of cancelation errors

packages/remix-dev/compiler/compiler.ts

@@ -44,9 +44,13 @@ export let create = async (ctx: Context): Promise<Compiler> => {
   };
 
   let compile = async () => {
-    let errCancel = (error: unknown) => {
+    let error: unknown | undefined = undefined;
+    let errCancel = (thrown: unknown) => {
+      if (error === undefined) {
+        error = thrown;
+      }
       cancel();
-      return err(error);
+      return err(thrown);
     };
 
     // reset channels
@@ -69,7 +73,7 @@ export let create = async (ctx: Context): Promise<Compiler> => {
 
     // css compilation
     let css = await tasks.css;
-    if (!css.ok) throw css.error;
+    if (!css.ok) throw error ?? css.error;
 
     // css bundle
     let cssBundleHref =
@@ -87,7 +91,7 @@ export let create = async (ctx: Context): Promise<Compiler> => {
     // js compilation (implicitly writes artifacts/js)
     // TODO: js task should not return metafile, but rather js assets
     let js = await tasks.js;
-    if (!js.ok) throw js.error;
+    if (!js.ok) throw error ?? js.error;
     let { metafile, hmr } = js.value;
 
     // artifacts/manifest
@@ -102,7 +106,7 @@ export let create = async (ctx: Context): Promise<Compiler> => {
 
     // server compilation
     let server = await tasks.server;
-    if (!server.ok) throw server.error;
+    if (!server.ok) throw error ?? server.error;
     // artifacts/server
     writes.server = Server.write(ctx.config, server.value);