UPDATE: Dump of initial files

base/src/test/test_fn_concatenate.rs

@@ -0,0 +1,34 @@
+#![allow(clippy::unwrap_used)]
+
+use crate::test::util::new_empty_model;
+
+#[test]
+fn fn_concatenate_args_number() {
+    let mut model = new_empty_model();
+    model._set("A1", "=CONCATENATE()");
+
+    model.evaluate();
+
+    assert_eq!(model._get_text("A1"), *"#ERROR!");
+}
+
+#[test]
+fn fn_concatenate() {
+    let mut model = new_empty_model();
+    model._set("A1", "Hello");
+    model._set("A2", " my ");
+    model._set("A3", "World");
+
+    model._set("B1", r#"=CONCATENATE(A1, A2, A3, "!")"#);
+    // This will break once we implement the implicit intersection operator
+    // It should be:
+    // model._set("B2", r#"=CONCATENATE(@A1:A3, "!")"#);
+    model._set("B2", r#"=CONCATENATE(A1:A3, "!")"#);
+    model._set("B3", r#"=CONCAT(A1:A3, "!")"#);
+
+    model.evaluate();
+
+    assert_eq!(model._get_text("B1"), *"Hello my World!");
+    assert_eq!(model._get_text("B2"), *" my !");
+    assert_eq!(model._get_text("B3"), *"Hello my World!");
+}