Command tests (#922)

* WIP command tests

* Finish marking todo tests

* update

* update

* Windows cd test ignoring

crates/nu-command/tests/commands/all.rs

@@ -0,0 +1,57 @@
+use nu_test_support::{nu, pipeline};
+
+#[test]
+fn checks_all_rows_are_true() {
+    let actual = nu!(
+        cwd: ".", pipeline(
+        r#"
+                echo  [ "Andrés", "Andrés", "Andrés" ] 
+                | all? $it == "Andrés"
+        "#
+    ));
+
+    assert_eq!(actual.out, "true");
+}
+
+#[test]
+fn checks_all_rows_are_false_with_param() {
+    let actual = nu!(
+        cwd: ".", pipeline(
+        r#"
+                [1, 2, 3, 4] | all? { |a| $a >= 5 }
+        "#
+    ));
+
+    assert_eq!(actual.out, "false");
+}
+
+#[test]
+fn checks_all_rows_are_true_with_param() {
+    let actual = nu!(
+        cwd: ".", pipeline(
+        r#"
+                [1, 2, 3, 4] | all? { |a| $a < 5 }
+        "#
+    ));
+
+    assert_eq!(actual.out, "true");
+}
+
+#[test]
+fn checks_all_columns_of_a_table_is_true() {
+    let actual = nu!(
+        cwd: ".", pipeline(
+        r#"
+                echo [
+                        [  first_name, last_name,   rusty_at, likes  ];
+                        [      Andrés,  Robalino, 10/11/2013,   1    ]
+                        [    Jonathan,    Turner, 10/12/2013,   1    ]
+                        [      Darren, Schroeder, 10/11/2013,   1    ]
+                        [      Yehuda,      Katz, 10/11/2013,   1    ]
+                ]
+                | all? likes > 0
+        "#
+    ));
+
+    assert_eq!(actual.out, "true");
+}