Add test for wasm_executor

substrate/executor/src/wasm_executor.rs

@@ -582,6 +582,29 @@ mod tests {
 		assert_eq!(expected, ext);
 	}
 
+	#[test]
+	fn clear_prefix_should_work() {
+		let mut ext = TestExternalities::default();
+		ext.set_storage(b"aaa".to_vec(), b"1".to_vec());
+		ext.set_storage(b"aab".to_vec(), b"2".to_vec());
+		ext.set_storage(b"aba".to_vec(), b"3".to_vec());
+		ext.set_storage(b"abb".to_vec(), b"4".to_vec());
+		ext.set_storage(b"bbb".to_vec(), b"5".to_vec());
+		let test_code = include_bytes!("../wasm/target/wasm32-unknown-unknown/release/runtime_test.compact.wasm");
+
+		// This will clear all entries which prefix is "ab".
+		let output = WasmExecutor.call(&mut ext, &test_code[..], "test_clear_prefix", b"ab").unwrap();
+
+		assert_eq!(output, b"all ok!".to_vec());
+
+		let expected: HashMap<_, _> = map![
+			b"aaa".to_vec() => b"1".to_vec(),
+			b"aab".to_vec() => b"2".to_vec(),
+			b"bbb".to_vec() => b"5".to_vec()
+		];
+		assert_eq!(expected, ext);
+	}
+
 	#[test]
 	fn blake2_256_should_work() {
 		let mut ext = TestExternalities::default();

substrate/executor/wasm/src/lib.rs

@@ -11,7 +11,7 @@ extern crate substrate_runtime_io as runtime_io;
 extern crate substrate_runtime_sandbox as sandbox;
 
 use runtime_io::{
-	set_storage, storage, print, blake2_256,
+	set_storage, storage, clear_prefix, print, blake2_256,
 	twox_128, twox_256, ed25519_verify, enumerated_trie_root
 };
 
@@ -29,6 +29,10 @@ impl_stubs!(
 		print("finished!");
 		b"all ok!".to_vec()
 	},
+	test_clear_prefix NO_DECODE => |input| {
+		clear_prefix(input);
+		b"all ok!".to_vec()
+	},
 	test_empty_return NO_DECODE => |_| Vec::new(),
 	test_panic NO_DECODE => |_| panic!("test panic"),
 	test_conditional_panic NO_DECODE => |input: &[u8]| {