| # UI Tests |
| |
| This folder contains `rustc`'s |
| [UI tests](https://rustc-dev-guide.rust-lang.org/tests/ui.html). |
| |
| ## Test Directives (Headers) |
| |
| Typically, a UI test will have some test directives / headers which are |
| special comments that tell compiletest how to build and intepret a test. |
| |
| As part of an on-going effort to rewrite compiletest |
| (see <https://github.com/rust-lang/compiler-team/issues/536>), a major |
| change proposal to change legacy compiletest-style headers `// <directive>` |
| to [`ui_test`](https://github.com/oli-obk/ui_test)-style headers |
| `//@ <directive>` was accepted (see |
| <https://github.com/rust-lang/compiler-team/issues/512>. |
| |
| An example directive is `ignore-test`. In legacy compiletest style, the header |
| would be written as |
| |
| ```rs |
| // ignore-test |
| ``` |
| |
| but in `ui_test` style, the header would be written as |
| |
| ```rs |
| //@ ignore-test |
| ``` |
| |
| compiletest is changed to accept only `//@` directives for UI tests |
| (currently), and will reject and report an error if it encounters any |
| comments `// <content>` that may be parsed as an legacy compiletest-style |
| test header. To fix this, you should migrate to the `ui_test`-style header |
| `//@ <content>`. |
