Add tests around Option[] type

Author: mildred

tests/test_option.nim

@@ -0,0 +1,40 @@
+import std/unittest
+import std/options
+
+import easy_sqlite3
+
+proc returnOptionNone(): tuple[col: Option[int]] {.importdb: "SELECT NULL;".}
+proc returnOptionSome(): tuple[col: Option[int]] {.importdb: "SELECT 1;".}
+
+proc takeOption(col: Option[int]): tuple[val: int, is_null: bool] {.importdb: "SELECT COALESCE($col, 0), $col IS NULL".}
+
+iterator options(a: Option[int], b: Option[int], c: Option[int]): tuple[val: Option[int]] {.importdb: "VALUES ($a+1), ($b+1), ($c+1)".} = discard
+
+suite "option":
+  setup:
+    var db = initDatabase(":memory:")
+
+  test "return option none":
+    let col = db.returnOptionNone().col
+    check col.is_none()
+
+  test "return option some":
+    let col = db.returnOptionSome().col
+    check col.is_some()
+    check col.get == 1
+
+  test "take option none":
+    let res = db.takeOption(none(int))
+    check res.is_null
+    check res.val == 0
+
+  test "take option some":
+    let res = db.takeOption(some(1))
+    check not res.is_null
+    check res.val == 1
+
+  test "iterator options":
+    var res: seq[Option[int]] = @[]
+    for row in db.options(some(1), none(int), some(2)):
+      res.add(row.val)
+    check res == @[some(2), none(int), some(3)]