Specialize polymorphic values before binding to pattern

Closes #2811

compiler/test_mono/src/tests.rs

@@ -1282,6 +1282,17 @@ fn issue_2583_specialize_errors_behind_unified_branches() {
     )
 }
 
+#[mono_test]
+fn issue_2811() {
+    indoc!(
+        r#"
+        x = Command { tool: "bash" }
+        Command c = x
+        c.tool
+        "#
+    )
+}
+
 // #[ignore]
 // #[mono_test]
 // fn static_str_closure() {