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|
#![allow(unused_assignments, unused_variables)]
fn main() {
// Initialize test constants in a way that cannot be determined at compile time, to ensure
// rustc and LLVM cannot optimize out statements (or coverage counters) downstream from
// dependent conditions.
let is_true = std::env::args().len() == 1;
let is_false = ! is_true;
let mut some_string = Some(String::from("the string content"));
println!(
"The string or alt: {}"
,
some_string
.
unwrap_or_else
(
||
{
let mut countdown = 0;
if is_false {
countdown = 10;
}
"alt string 1".to_owned()
}
)
);
some_string = Some(String::from("the string content"));
let
a
=
||
{
let mut countdown = 0;
if is_false {
countdown = 10;
}
"alt string 2".to_owned()
};
println!(
"The string or alt: {}"
,
some_string
.
unwrap_or_else
(
a
)
);
some_string = None;
println!(
"The string or alt: {}"
,
some_string
.
unwrap_or_else
(
||
{
let mut countdown = 0;
if is_false {
countdown = 10;
}
"alt string 3".to_owned()
}
)
);
some_string = None;
let
a
=
||
{
let mut countdown = 0;
if is_false {
countdown = 10;
}
"alt string 4".to_owned()
};
println!(
"The string or alt: {}"
,
some_string
.
unwrap_or_else
(
a
)
);
let
quote_closure
=
|val|
{
let mut countdown = 0;
if is_false {
countdown = 10;
}
format!("'{}'", val)
};
println!(
"Repeated, quoted string: {:?}"
,
std::iter::repeat("repeat me")
.take(5)
.map
(
quote_closure
)
.collect::<Vec<_>>()
);
let
_unused_closure
=
|
mut countdown
|
{
if is_false {
countdown = 10;
}
"closure should be unused".to_owned()
};
let mut countdown = 10;
let _short_unused_closure = | _unused_arg: u8 | countdown += 1;
// Macros can sometimes confuse the coverage results. Compare this next assignment, with an
// unused closure that invokes the `println!()` macro, with the closure assignment above, that
// does not use a macro. The closure above correctly shows `0` executions.
let _short_unused_closure = | _unused_arg: u8 | println!("not called");
// The closure assignment above is executed, with a line count of `1`, but the `println!()`
// could not have been called, and yet, there is no indication that it wasn't...
// ...but adding block braces gives the expected result, showing the block was not executed.
let _short_unused_closure_block = | _unused_arg: u8 | { println!("not called") };
let _shortish_unused_closure = | _unused_arg: u8 | {
println!("not called")
};
let _as_short_unused_closure = |
_unused_arg: u8
| { println!("not called") };
let _almost_as_short_unused_closure = |
_unused_arg: u8
| { println!("not called") }
;
}
|
