Add tests for printing of NonZero-optimized enums in Rust

gdb/testsuite/ChangeLog:
2016-06-25  Manish Goregaokar  <manish@mozilla.com>

    PR gdb/20239
    * gdb.rust/simple.rs: Add more tests for printing NonZero enums.
    * gdb.rust/simple.exp: Add test expectations for new NonZero tests.

gdb/testsuite/ChangeLog

@@ -1,3 +1,9 @@
+2016-06-25  Manish Goregaokar  <manish@mozilla.com>
+
+	PR gdb/20239
+	* gdb.rust/simple.rs: Add more tests for printing NonZero enums.
+	* gdb.rust/simple.exp: Add test expectations for new NonZero tests.
+
 2016-06-24  David Taylor  <dtaylor@emc.com>
 
 	* gdb.base/offsets.exp: New file.

gdb/testsuite/gdb.rust/simple.exp

@@ -169,6 +169,17 @@ gdb_test "print ..5" " = .*::ops::RangeTo.* \\{end: 5\\}"
 gdb_test "print 5.." " = .*::ops::RangeFrom.* \\{start: 5\\}"
 gdb_test "print .." " = .*::ops::RangeFull"
 
+gdb_test "print str_some" \
+    " = core::option::Option<collections::string::String>::Some\\(collections::string::String .*"
+gdb_test "print str_none" " = core::option::Option<collections::string::String>::None"
+gdb_test "print int_some" " = core::option::Option::Some\\(1\\)"
+gdb_test "print int_none" " = core::option::Option::None"
+gdb_test "print box_some" " = core::option::Option<Box<u8>>::Some\\(.*\\)"
+gdb_test "print box_none" " = core::option::Option<Box<u8>>::None"
+gdb_test "print custom_some" \
+    " = simple::NonZeroOptimized::Value\\(collections::string::String .*"
+gdb_test "print custom_none" " = simple::NonZeroOptimized::Empty"
+
 proc test_one_slice {svar length base range} {
     global hex
 

gdb/testsuite/gdb.rust/simple.rs

@@ -38,6 +38,12 @@ enum MoreComplicated {
     Four{this: bool, is: u8, a: char, struct_: u64, variant: u32},
 }
 
+// tests the nonzero optimization, but fields are reversed
+enum NonZeroOptimized {
+    Empty,
+    Value(String),
+}
+
 fn diff2(x: i32, y: i32) -> i32 {
     x - y
 }
@@ -92,6 +98,17 @@ fn main () {
     let to1 = &w[..3];
     let to2 = &slice[..1];
 
+    // tests for enum optimizations
+
+    let str_some = Some("hi".to_string());
+    let str_none = None::<String>;
+    let box_some = Some(Box::new(1u8));
+    let box_none = None::<Box<u8>>;
+    let int_some = Some(1u8);
+    let int_none = None::<u8>;
+    let custom_some = NonZeroOptimized::Value("hi".into());
+    let custom_none = NonZeroOptimized::Empty;
+
     println!("{}, {}", x.0, x.1);        // set breakpoint here
     println!("{}", diff2(92, 45));
 }