Adds new tests and updates old ones.

New tests are added to test for additional cases that might be trickier to
handle with the new logic.

Old tests are updated where their expectations are no longer expected to hold true.
For instance: previously, lines would be treated separately, allowing any index
offset between columns on different rows, as long as they had the same row index
as decided by a separator. When this is no longer the case, some things need to
be adjusted.

src/commands/from_ssv.rs

@@ -185,6 +185,20 @@ mod tests {
         );
     }
 
+    #[test]
+    fn it_deals_with_single_column_input() {
+        let input = r#"
+            a
+            1
+            2
+        "#;
+        let result = string_to_table(input, false, 1);
+        assert_eq!(
+            result,
+            Some(vec![vec![owned("a", "1")], vec![owned("a", "2")]])
+        );
+    }
+
     #[test]
     fn it_ignores_headers_when_headerless() {
         let input = r#"
@@ -206,7 +220,7 @@ mod tests {
     fn it_returns_none_given_an_empty_string() {
         let input = "";
         let result = string_to_table(input, true, 1);
-        assert_eq!(result, None);
+        assert!(result.is_none());
     }
 
     #[test]
@@ -240,11 +254,54 @@ mod tests {
         let trimmed = |s: &str| s.trim() == s;
 
         let result = string_to_table(input, false, 2).unwrap();
-        assert_eq!(
-            true,
-            result
+        assert!(result
             .iter()
-                .all(|row| row.iter().all(|(a, b)| trimmed(a) && trimmed(b)))
+            .all(|row| row.iter().all(|(a, b)| trimmed(a) && trimmed(b))))
+    }
+
+    #[test]
+    fn it_keeps_empty_columns() {
+        let input = r#"
+            colA   col B     col C
+                   val2      val3
+            val4   val 5     val 6
+            val7             val8
+        "#;
+
+        let result = string_to_table(input, false, 2).unwrap();
+        assert_eq!(
+            result,
+            vec![
+                vec![
+                    owned("colA", ""),
+                    owned("col B", "val2"),
+                    owned("col C", "val3")
+                ],
+                vec![
+                    owned("colA", "val4"),
+                    owned("col B", "val 5"),
+                    owned("col C", "val 6")
+                ],
+                vec![
+                    owned("colA", "val7"),
+                    owned("col B", ""),
+                    owned("col C", "val8")
+                ],
+            ]
+        )
+    }
+
+    #[test]
+    fn it_drops_trailing_values() {
+        let input = r#"
+            colA   col B
+            val1   val2   trailing value that should be ignored
+        "#;
+
+        let result = string_to_table(input, false, 2).unwrap();
+        assert_eq!(
+            result,
+            vec![vec![owned("colA", "val1"), owned("col B", "val2"),],]
         )
     }
 }