Move some Encodable/Decodable tests.

Round-trip encoding/decoding of many types is tested in
`compiler/rustc_serialize/tests/opaque.rs`. There is also a small amount
of encoding/decoding testing in three files in `tests/ui-fulldeps`.

There is no obvious reason why these three files are necessary. They
were originally added in 2014. Maybe it wasn't possible for a proc
macro to run in a unit test back then?

This commit just moves the testing from those three files into the unit
test.

compiler/rustc_serialize/tests/opaque.rs

@@ -251,3 +251,42 @@ fn test_tuples() {
     check_round_trip(vec![(1234567isize, 100000000000000u64, 99999999999999i64)]);
     check_round_trip(vec![(String::new(), "some string".to_string())]);
 }
+
+#[test]
+fn test_unit_like_struct() {
+    #[derive(Encodable, Decodable, PartialEq, Debug)]
+    struct UnitLikeStruct;
+
+    check_round_trip(vec![UnitLikeStruct]);
+}
+
+#[test]
+fn test_box() {
+    #[derive(Encodable, Decodable, PartialEq, Debug)]
+    struct A {
+        foo: Box<[bool]>,
+    }
+
+    let obj = A { foo: Box::new([true, false]) };
+    check_round_trip(vec![obj]);
+}
+
+#[test]
+fn test_cell() {
+    use std::cell::{Cell, RefCell};
+
+    #[derive(Encodable, Decodable, PartialEq, Debug)]
+    struct A {
+        baz: isize,
+    }
+
+    #[derive(Encodable, Decodable, PartialEq, Debug)]
+    struct B {
+        foo: Cell<bool>,
+        bar: RefCell<A>,
+    }
+
+    let obj = B { foo: Cell::new(true), bar: RefCell::new(A { baz: 2 }) };
+    check_round_trip(vec![obj]);
+}
+

tests/ui-fulldeps/deriving-encodable-decodable-box.rs

@@ -1,34 +0,0 @@
-// run-pass
-
-#![allow(unused_imports)]
-#![feature(rustc_private)]
-
-extern crate rustc_macros;
-extern crate rustc_serialize;
-
-// Necessary to pull in object code as the rest of the rustc crates are shipped only as rmeta
-// files.
-#[allow(unused_extern_crates)]
-extern crate rustc_driver;
-
-use rustc_macros::{Decodable, Encodable};
-use rustc_serialize::opaque::{MemDecoder, MemEncoder};
-use rustc_serialize::{Decodable, Encodable, Encoder};
-
-#[derive(Encodable, Decodable)]
-struct A {
-    foo: Box<[bool]>,
-}
-
-fn main() {
-    let obj = A { foo: Box::new([true, false]) };
-
-    let mut encoder = MemEncoder::new();
-    obj.encode(&mut encoder);
-    let data = encoder.finish();
-
-    let mut decoder = MemDecoder::new(&data, 0);
-    let obj2 = A::decode(&mut decoder);
-
-    assert_eq!(obj.foo, obj2.foo);
-}

tests/ui-fulldeps/deriving-encodable-decodable-cell-refcell.rs

@@ -1,44 +0,0 @@
-// run-pass
-
-#![allow(unused_imports)]
-// This briefly tests the capability of `Cell` and `RefCell` to implement the
-// `Encodable` and `Decodable` traits via `#[derive(Encodable, Decodable)]`
-#![feature(rustc_private)]
-
-extern crate rustc_macros;
-extern crate rustc_serialize;
-
-// Necessary to pull in object code as the rest of the rustc crates are shipped only as rmeta
-// files.
-#[allow(unused_extern_crates)]
-extern crate rustc_driver;
-
-use rustc_macros::{Decodable, Encodable};
-use rustc_serialize::opaque::{MemDecoder, MemEncoder};
-use rustc_serialize::{Decodable, Encodable, Encoder};
-use std::cell::{Cell, RefCell};
-
-#[derive(Encodable, Decodable)]
-struct A {
-    baz: isize,
-}
-
-#[derive(Encodable, Decodable)]
-struct B {
-    foo: Cell<bool>,
-    bar: RefCell<A>,
-}
-
-fn main() {
-    let obj = B { foo: Cell::new(true), bar: RefCell::new(A { baz: 2 }) };
-
-    let mut encoder = MemEncoder::new();
-    obj.encode(&mut encoder);
-    let data = encoder.finish();
-
-    let mut decoder = MemDecoder::new(&data, 0);
-    let obj2 = B::decode(&mut decoder);
-
-    assert_eq!(obj.foo.get(), obj2.foo.get());
-    assert_eq!(obj.bar.borrow().baz, obj2.bar.borrow().baz);
-}

tests/ui-fulldeps/issue-14021.rs

@@ -1,33 +0,0 @@
-// run-pass
-
-#![allow(unused_mut)]
-#![allow(unused_imports)]
-#![feature(rustc_private)]
-
-extern crate rustc_macros;
-extern crate rustc_serialize;
-
-// Necessary to pull in object code as the rest of the rustc crates are shipped only as rmeta
-// files.
-#[allow(unused_extern_crates)]
-extern crate rustc_driver;
-
-use rustc_macros::{Decodable, Encodable};
-use rustc_serialize::opaque::{MemDecoder, MemEncoder};
-use rustc_serialize::{Decodable, Encodable, Encoder};
-
-#[derive(Encodable, Decodable, PartialEq, Debug)]
-struct UnitLikeStruct;
-
-pub fn main() {
-    let obj = UnitLikeStruct;
-
-    let mut encoder = MemEncoder::new();
-    obj.encode(&mut encoder);
-    let data = encoder.finish();
-
-    let mut decoder = MemDecoder::new(&data, 0);
-    let obj2 = UnitLikeStruct::decode(&mut decoder);
-
-    assert_eq!(obj, obj2);
-}