Qute: relax cdi/inject namespace validation

- do not fail the build if a safe expression is used

extensions/qute/deployment/src/main/java/io/quarkus/qute/deployment/QuteProcessor.java

@@ -1783,7 +1783,7 @@ private static BeanInfo findBean(Expression expression, IndexView index,
         Expression.Part firstPart = expression.getParts().get(0);
         if (firstPart.isVirtualMethod()) {
             incorrectExpressions.produce(new IncorrectExpressionBuildItem(expression.toOriginalString(),
-                    "The inject: namespace must be followed by a bean name",
+                    "The " + expression.getNamespace() + ": namespace must be followed by a bean name",
                     expression.getOrigin()));
             return null;
         }
@@ -1793,8 +1793,12 @@ private static BeanInfo findBean(Expression expression, IndexView index,
             return bean;
         } else {
             // User is injecting a non-existing bean
-            incorrectExpressions.produce(new IncorrectExpressionBuildItem(expression.toOriginalString(),
-                    beanName, null, expression.getOrigin()));
+            if (!expression.toOriginalString().endsWith("or(null)")) {
+                // Fail unless a safe expression
+                // Note that foo.val?? becomes foo.val.or(null) during parsing
+                incorrectExpressions.produce(new IncorrectExpressionBuildItem(expression.toOriginalString(),
+                        beanName, null, expression.getOrigin()));
+            }
             return null;
         }
     }

extensions/qute/deployment/src/test/java/io/quarkus/qute/deployment/inject/NamedBeanNotFoundSafeTest.java

@@ -0,0 +1,29 @@
+package io.quarkus.qute.deployment.inject;
+
+import static org.junit.jupiter.api.Assertions.assertEquals;
+
+import jakarta.inject.Inject;
+
+import org.jboss.shrinkwrap.api.asset.StringAsset;
+import org.junit.jupiter.api.Test;
+import org.junit.jupiter.api.extension.RegisterExtension;
+
+import io.quarkus.qute.Template;
+import io.quarkus.test.QuarkusUnitTest;
+
+public class NamedBeanNotFoundSafeTest {
+
+    @RegisterExtension
+    static final QuarkusUnitTest config = new QuarkusUnitTest()
+            .withApplicationRoot(root -> root
+                    .addAsResource(new StringAsset("{cdi:ping.val??}"), "templates/ping.html"));
+
+    @Inject
+    Template ping;
+
+    @Test
+    public void testTemplate() {
+        assertEquals("", ping.render());
+    }
+
+}