Issue #69: Change `range` to require only one arg

Currently range is hard-coded to take both max and min. This is
unhelpful in cases where we may only want to check one of the bounds.

Update so that it behaves more like the `length` validator and can take
either max or min, as well as both. Also ensure that at least one of
them is supplied.

3 files changed, 5 insertions, 16 deletions

diff --git a/validator_derive/tests/compile-fail/range/missing_arg.rs b/validator_derive/tests/compile-fail/range/missing_arg.rs
deleted file mode 100644
index 3aed1f0..0000000
--- a/validator_derive/tests/compile-fail/range/missing_arg.rs
+++ /dev/null
@@ -1,15 +0,0 @@
-#![feature(attr_literals)]
-
-#[macro_use] extern crate validator_derive;
-extern crate validator;
-use validator::Validate;
-
-#[derive(Validate)]
-//~^ ERROR: proc-macro derive panicked
-//~^^ HELP: Invalid attribute #[validate] on field `s`: Validator `range` requires 2 arguments: `min` and `max`
-struct Test {
-    #[validate(range(min = 2.0))]
-    s: i32,
-}
-
-fn main() {}
diff --git a/validator_derive/tests/compile-fail/range/no_args.rs b/validator_derive/tests/compile-fail/range/no_args.rs
index c2bdd03..b097b0a 100644
--- a/validator_derive/tests/compile-fail/range/no_args.rs
+++ b/validator_derive/tests/compile-fail/range/no_args.rs
@@ -4,7 +4,7 @@ use validator::Validate;
 
 #[derive(Validate)]
 //~^ ERROR: proc-macro derive panicked
-//~^^ HELP: Invalid attribute #[validate] on field `s`: Validator `range` requires 2 arguments: `min` and `max`
+//~^^ HELP: Invalid attribute #[validate] on field `s`: Validator `range` requires at least 1 argument out of `min` and `max`
 struct Test {
     #[validate(range())]
     s: i32,
diff --git a/validator_derive/tests/run-pass/range.rs b/validator_derive/tests/run-pass/range.rs
index e35f3df..520dd64 100644
--- a/validator_derive/tests/run-pass/range.rs
+++ b/validator_derive/tests/run-pass/range.rs
@@ -24,6 +24,10 @@ struct Test {
     s8: u8,
     #[validate(range(min = 18.0, max = 22))]
     s9: Option<u8>,
+    #[validate(range(min = 18.0))]
+    s10: Option<u8>,
+    #[validate(range(max = 18.0))]
+    s11: Option<u8>,
 }
 
 fn main() {}