diff --git a/src/tests/ui.md b/src/tests/ui.md index c8536b00..1190c264 100644 --- a/src/tests/ui.md +++ b/src/tests/ui.md @@ -202,6 +202,12 @@ several ways to match the message with the line (see the examples below): * `~|`: Associates the error level and message with the *same* line as the *previous comment*. This is more convenient than using multiple carets when there are multiple messages associated with the same line. +* `~v`: Associates the error level and message with the *next* error + annotation line. Each symbol (`v`) that you add adds a line to this, so `~vvv` + is three lines below the error annotation line. +* `~?`: Used to match error levels and messages with errors not having line + information. These can be placed on any line in the test file, but are + conventionally placed at the end. Example: @@ -270,10 +276,35 @@ fn main() { //~| ERROR this pattern has 1 field, but the corresponding tuple struct has 3 fields [E0023] ``` +#### Positioned above error line + +Use the `//~v` idiom with number of v's in the string to indicate the number +of lines below. This is typically used in lexer or parser tests matching on errors like unclosed +delimiter or unclosed literal happening at the end of file. + +```rust,ignore +// ignore-tidy-trailing-newlines +//~v ERROR this file contains an unclosed delimiter +fn main((ؼ +``` + +#### Error without line information + +Use `//~?` to match an error without line information. +`//~?` is precise and will not match errors if their line information is available. +It should be preferred to using `error-pattern`, which is imprecise and non-exhaustive. + +```rust,ignore +//@ compile-flags: --print yyyy + +//~? ERROR unknown print request: `yyyy` +``` + ### `error-pattern` -The `error-pattern` [directive](directives.md) can be used for messages that don't -have a specific span. +The `error-pattern` [directive](directives.md) can be used for runtime messages, which don't +have a specific span, or for compile time messages if imprecise matching is required due to +multi-line platform specific diagnostics. Let's think about this test: @@ -300,7 +331,9 @@ fn main() { } ``` -But for strict testing, try to use the `ERROR` annotation as much as possible. +But for strict testing, try to use the `ERROR` annotation as much as possible, +including `//~?` annotations for diagnostics without span. +For compile time diagnostics `error-pattern` should very rarely be necessary. ### Error levels @@ -353,7 +386,7 @@ would be a `.mir.stderr` and `.thir.stderr` file with the different outputs of the different revisions. > Note: cfg revisions also work inside the source code with `#[cfg]` attributes. -> +> > By convention, the `FALSE` cfg is used to have an always-false config. ## Controlling pass/fail expectations