Public extrinsic apply doesn't panic (#178)

* Merge remote-tracking branch 'origin/master' into gav-xts-dont-panic

* Update wasm.

* consensus, session and staking all panic-safe.

* Democracy doesn't panic in apply.

* Fix tests.

* Extra helper macro, council depanicked.

* Fix one test.

* Fix up all council tests. No panics!

* Council voting depanicked.

* utilise hygene

substrate/substrate/runtime-support/src/lib.rs

@@ -44,3 +44,62 @@ mod hashable;
 pub use self::storage::{StorageVec, StorageList, StorageValue, StorageMap};
 pub use self::hashable::Hashable;
 pub use self::dispatch::{Parameter, Dispatchable, Callable, AuxDispatchable, AuxCallable, IsSubType, IsAuxSubType};
+pub use runtime_io::print;
+
+#[macro_export]
+macro_rules! fail {
+	( $y:expr ) => {{
+		$crate::print($y);
+		return;
+	}}
+}
+
+#[macro_export]
+macro_rules! ensure {
+	( $x:expr, $y:expr ) => {{
+		if !$x {
+			fail!($y);
+		}
+	}};
+	($x:expr) => {{
+		if !$x {
+			$crate::print("Bailing! Cannot ensure: ");
+			$crate::print(stringify!($x));
+			return;
+		}
+	}}
+}
+
+#[macro_export]
+macro_rules! ensure_unwrap {
+	($x:expr, $y: expr) => {
+		if let Some(v) = $x {
+			v
+		} else {
+			fail!{$y}
+		}
+	}
+}
+
+#[macro_export]
+macro_rules! ensure_unwrap_err {
+	($x:expr, $y: expr) => {
+		if let Err(v) = $x {
+			v
+		} else {
+			fail!{$y}
+		}
+	}
+}
+
+#[macro_export]
+#[cfg(feature = "std")]
+macro_rules! assert_noop {
+	( $( $x:tt )* ) => {
+		let h = runtime_io::storage_root();
+		{
+			$( $x )*
+		}
+		assert_eq!(h, runtime_io::storage_root());
+	}
+}