Removes 'main{' and '}' from listing 11-12 so it compiles.

[FabienTregan]

Code snipet was not marked as " ```rust,ignore", then when copied it was surrounded with a "main {}" block which prevented it fom compiling.

[steveklabnik]

Hm, sorry, I'm a bit confused. What is happening here? This shouldn't have any main in it at all?

[FabienTregan]

Ok, I try to give a better description of what I wanted to solved with this commit :

-I checkout version b56c8f0
-I mdbook to generate html version of the book
-from /book/2018-edition/book/ch11-03-test-organization.html , I go to listing 11-12 and use the copy button
-when I past it, all the code is included (without added indentation) into a fn main {..}

#![allow(unused_variables)]
fn main() {
pub fn add_two(a: i32) -> i32 {
internal_adder(a, 2)
}

fn internal_adder(a: i32, b: i32) -> i32 {
a + b
}

#[cfg(test)]
mod tests {
use super::*;

#[test]
fn internal() {
assert_eq!(4, internal_adder(2, 2));
}
}
}

This does compile (with rustc src/lib.rs in my dedicated 'learning rust' folder), but if I try cargo test (and this listing is supposed to show how to test private functions) I get :

error[E0425]: cannot find function internal_adder in this scope
--> src\lib.rs:20:23
|
20 | assert_eq!(4, internal_adder(2, 2));
| ^^^^^^^^^^^^^^ not found in this scope

warning: unused import: super::*
--> src\lib.rs:16:9
|
16 | use super::*;
| ^^^^^^^^
|
= note: #[warn(unused_imports)] on by default

error: aborting due to previous error

For more information about this error, try rustc --explain E0425.
error: Could not compile adder.

To learn more, run the command again with --verbose.`

Having a public function inside the main function seemed strange to me (I'm just learning rust). Also the fact that there is a missing indentation level inside main seemed suspect. I tryed on listing 11-13, saw that the main function was not added ; It apparently came from the added ,ignore in first line of listing 11-13 in the /book/2018-edition/src/ch11-03-test-organization.md file. I tryed adding ,ignore in listing 11-12 and it solved the problem, but I'm no longer sure it was the good solution to this problem.

Hope this helps,
Fabien.

[carols10cents]

The playground integration and mdbook test auto wraps examples in main, a better solution than adding ignore is to add a comment with a fake main so that a wrapper main doesn't get added, see https://github.com/rust-lang/book/blame/master/second-edition/src/ch11-01-writing-tests.md#L51 for an example

[steveklabnik]

I'm a bit surprised it does given the inclusion of #[test], but makes sense. Yes, I'd rather add an explicit main than ignore the test.

[FabienTregan]

I updated my branch according to @carols10cents ' recommendation, thank you.

[steveklabnik]

Thank you!