Add another check for render doneness for validation failure

packages/gatsby-recipes/src/renderer/render.js

@@ -268,10 +268,18 @@ const render = (recipe, cb, inputs = {}, isApply, isStream, name) => {
         // If there's still nothing on the queue and we've drained the queue, that means we're done.
       } else if (isDrained && queue.length === 0) {
         return true
+        // If there's one resource & it fails validation, it doesn't go into the queue
+        // so we check if inFlightCache is empty & all resources have an error.
+      } else if (
+        !resources.some(r => !r.error) &&
+        ![...inFlightCache.values()].some(a => a)
+      ) {
+        return true
       }
 
       return false
     }
+
     if (isDone()) {
       // Rerender with the resources and resolve the data from the cache.
       emitter.emit(`done`, resources)

packages/gatsby-recipes/src/validate-steps.js

@@ -11,17 +11,12 @@ module.exports = async steps => {
     }
   })
 
-  try {
-    const firstStepPlan = await render(steps[0])
-    if (firstStepPlan.length) {
-      errors.push({
-        step: 0,
-        validationError: `Resources should not be placed in the introduction step (0)`,
-      })
-    }
-  } catch (e) {
-    // This means the first step has a syntax error which is already
-    // addressed above.
+  const firstStepPlan = await render(steps[0])
+  if (firstStepPlan.length) {
+    errors.push({
+      step: 0,
+      validationError: `Resources should not be placed in the introduction step (0)`,
+    })
   }
 
   return errors