Tests support control chars widths 0 or 1

[correabuscar]

closes #788

fixed a couple of nits too

[gyscos]

Thanks for the PR!

I just pushed a change that only marks some backends "persistent". The puppet backend defaults to non-persistent.
In the print buffer, we now only skip similar chars on persistent backends. What this means is that for the pupper backend, we will flush the entire screen and not just the diffs, so we shouldn't have to use the lowercase a workaround.

[correabuscar]

In the print buffer, we now only skip similar chars on persistent backends.

that commit is not pushed yet? I only see this one: 2a7b368

therefore is_persistent isn't used by anything:

$ grep -nrIFw is_persistent
cursive-core/src/backend.rs:88:    fn is_persistent(&self) -> bool {
cursive/src/backends/curses/pan.rs:380:    fn is_persistent(&self) -> bool {
cursive/src/backends/curses/n.rs:325:    fn is_persistent(&self) -> bool {
cursive/src/backends/crossterm.rs:330:    fn is_persistent(&self) -> bool {
cursive/src/backends/termion.rs:270:    fn is_persistent(&self) -> bool {

I tested via:

$ cargo test --example select_test -- --nocapture
    Finished `test` profile [unoptimized + debuginfo] target(s) in 0.08s
     Running unittests examples/select_test.rs (target/x86_64-unknown-linux-gnu/debug/examples/select_test-d45f2e1e4022a737)

running 3 tests
captured piece:
x01234567890123456789012345678901234567890123456789012345678901234567890123456789x
0                                                                                |
1                                                                                |
2                           ┌┤ Where are you from? ├┐                            |
3                           │      Abidjan       ▒  │                            |
4                           │     Abu Dhabi      |  │                            |
5                           │       Abuja        |  │                            |
6                           │       Accra        |  │                            |
7                           │     Adamstown      |  │                            |
8                           │    Addis Ababa     |  │                            |
9                           │      Algiers       |  │                            |
0                           │       Alofi        |  │                            |
1                           │       Amman        |  │                            |
2                           │     Amsterdam      |  │                            |
3                           └───────────────────────┘                            |
4                                                                                |
5                                                                                |
x--------------------------------------------------------------------------------x

captured piece:
x01234567890123456789012345678901234567890123456789012345678901234567890123456789x
0................................................................................|
1................................................................................|
2................................................................................|
3.............................  short nul 1str  .|...............................|
4.................................  1thru8 ......................................|
5...............................tabandnewline....................................|
6..................................bthru15.......................................|
7................................. 16thru1F......................................|
8................................   7Fonly  .....................................|
9..................................80thru89......................................|
0..................................8.thru93......................................|
1..................................94thru9D......................................|
2.............................     9Ethru9F     .▒...............................|
3................................................................................|
4................................................................................|
5................................................................................|
x--------------------------------------------------------------------------------x

captured piece:
x01234567890123456789012345678901234567890123456789012345678901234567890123456789x
0................................................................................|
1................................................................................|
2...........................                         ............................|
3...........................                          ...........................|
4...........................                          ...........................|
5.........................┌────────────────────────────┐.........................|
6.........................│ Abu.Dhabi is a.great.city! │ ........................|
7.........................│  .....         ...... ..   │ ........................|
8.........................│  ....     .     ....<Quit> │ ........................|
9.........................└────────────────────────────┘ ........................|
0..........................                          .   ........................|
1...........................                          ...........................|
2...........................                          ...........................|
3...........................                          ...........................|
4............................                         ...........................|
5................................................................................|
x--------------------------------------------------------------------------------x

test tests::displays ... ok
test tests::interacts ... ok
thread 'tests::control_chars_including_nul_when_on_screen' panicked at cursive/examples/select_test.rs:229:13:
assertion `left == right` failed: control chars \x8A thru \x93 should've been deleted from output
  left: 0
 right: 1
stack backtrace:
   0: rust_begin_unwind
             at /rustc/a70b2ae57713ed0e7411c059d582ab382fc4166a/library/std/src/panicking.rs:652:5
   1: core::panicking::panic_fmt
             at /rustc/a70b2ae57713ed0e7411c059d582ab382fc4166a/library/core/src/panicking.rs:72:14
   2: core::panicking::assert_failed_inner
             at /rustc/a70b2ae57713ed0e7411c059d582ab382fc4166a/library/core/src/panicking.rs:403:23
   3: core::panicking::assert_failed
             at /rustc/a70b2ae57713ed0e7411c059d582ab382fc4166a/library/core/src/panicking.rs:363:5
   4: select_test::tests::control_chars_including_nul_when_on_screen
             at ./examples/select_test.rs:229:13
   5: select_test::tests::control_chars_including_nul_when_on_screen::{{closure}}
             at ./examples/select_test.rs:129:52
   6: core::ops::function::FnOnce::call_once
             at /rustc/a70b2ae57713ed0e7411c059d582ab382fc4166a/library/core/src/ops/function.rs:250:5
   7: core::ops::function::FnOnce::call_once
             at /rustc/a70b2ae57713ed0e7411c059d582ab382fc4166a/library/core/src/ops/function.rs:250:5
note: Some details are omitted, run with `RUST_BACKTRACE=full` for a verbose backtrace.
test tests::control_chars_including_nul_when_on_screen ... FAILED

failures:

failures:
    tests::control_chars_including_nul_when_on_screen

test result: FAILED. 2 passed; 1 failed; 0 ignored; 0 measured; 0 filtered out; finished in 0.04s

error: test failed, to rerun pass `-p cursive --example select_test`

basically if you see lots of dots in the last 2 screens, it means it didn't change what was there before, it seems.

[gyscos]

Whoops indeed the last commit wasn't pushed :-'

[correabuscar]

I'll update in a sec, testing and such :)
Done.