summaryrefslogtreecommitdiffstats
path: root/src/test/ui/for-loop-while/label_break_value.rs
diff options
context:
space:
mode:
Diffstat (limited to '')
-rw-r--r--src/test/ui/for-loop-while/label_break_value.rs167
1 files changed, 167 insertions, 0 deletions
diff --git a/src/test/ui/for-loop-while/label_break_value.rs b/src/test/ui/for-loop-while/label_break_value.rs
new file mode 100644
index 000000000..ca9d71a7a
--- /dev/null
+++ b/src/test/ui/for-loop-while/label_break_value.rs
@@ -0,0 +1,167 @@
+// run-pass
+#![allow(dead_code)]
+#![allow(unused_assignments)]
+#![feature(label_break_value)]
+
+// Test control flow to follow label_break_value semantics
+fn label_break(a: bool, b: bool) -> u32 {
+ let mut v = 0;
+ 'b: {
+ v = 1;
+ if a {
+ break 'b;
+ }
+ v = 2;
+ if b {
+ break 'b;
+ }
+ v = 3;
+ }
+ return v;
+}
+
+// Test that values can be returned
+fn break_value(a: bool, b: bool) -> u32 {
+ let result = 'block: {
+ if a { break 'block 1; }
+ if b { break 'block 2; }
+ 3
+ };
+ result
+}
+
+// Test nesting of labeled blocks
+// here we only check that it compiles
+fn label_break_nested() {
+ 'b: {
+ println!("hi");
+ if false {
+ break 'b;
+ }
+ 'c: {
+ if false {
+ break 'b;
+ }
+ break 'c;
+ }
+ println!("hello");
+ if true {
+ break 'b;
+ }
+ }
+}
+
+// Tests for mixing labeled blocks with loop constructs
+// This function should be the identity function
+fn label_break_mixed(v: u32) -> u32 {
+ let mut r = 0;
+ 'b: {
+ // Unlabeled break still works
+ // (only crossing boundaries is an error)
+ loop {
+ break;
+ }
+ if v == 0 {
+ break 'b;
+ }
+ // Labeled breaking an inner loop still works
+ 'c: loop {
+ if r == 1 {
+ break 'c;
+ }
+ r += 1;
+ }
+ assert_eq!(r, 1);
+ if v == 1 {
+ break 'b;
+ }
+ // Labeled breaking an outer loop still works
+ 'd: loop {
+ {
+ if v == r {
+ break 'b;
+ }
+ if r == 5 {
+ break 'd;
+ }
+ r += 1;
+ }
+ }
+ assert_eq!(r, 5);
+ assert!(v > r);
+ // Here we test return from inside a labeled block
+ return v;
+ }
+ r
+}
+
+fn label_break_match(c: u8, xe: u8, ye: i8) {
+ let mut x = 0;
+ let y = 'a: {
+ match c {
+ 0 => break 'a 0,
+ v if { if v % 2 == 0 { break 'a 1; }; v % 3 == 0 } => { x += 1; },
+ v if { 'b: { break 'b v == 5; } } => { x = 41; },
+ _ => 'b: {
+ break 'b ();
+ },
+ }
+ x += 1;
+ -1
+ };
+
+ assert_eq!(x, xe);
+ assert_eq!(y, ye);
+}
+
+#[allow(unused_labels)]
+fn label_break_macro() {
+ macro_rules! mac1 {
+ ($target:lifetime, $val:expr) => {
+ break $target $val;
+ };
+ }
+ let x: u8 = 'a: {
+ 'b: {
+ mac1!('b, 1);
+ };
+ 0
+ };
+ assert_eq!(x, 0);
+ let x: u8 = 'a: {
+ 'b: {
+ if true {
+ mac1!('a, 1);
+ }
+ };
+ 0
+ };
+ assert_eq!(x, 1);
+}
+
+pub fn main() {
+ assert_eq!(label_break(true, false), 1);
+ assert_eq!(label_break(false, true), 2);
+ assert_eq!(label_break(false, false), 3);
+
+ assert_eq!(break_value(true, false), 1);
+ assert_eq!(break_value(false, true), 2);
+ assert_eq!(break_value(false, false), 3);
+
+ assert_eq!(label_break_mixed(0), 0);
+ assert_eq!(label_break_mixed(1), 1);
+ assert_eq!(label_break_mixed(2), 2);
+ assert_eq!(label_break_mixed(3), 3);
+ assert_eq!(label_break_mixed(4), 4);
+ assert_eq!(label_break_mixed(5), 5);
+ assert_eq!(label_break_mixed(6), 6);
+
+ label_break_match(0, 0, 0);
+ label_break_match(1, 1, -1);
+ label_break_match(2, 0, 1);
+ label_break_match(3, 2, -1);
+ label_break_match(5, 42, -1);
+ label_break_match(7, 1, -1);
+
+ label_break_macro();
+}