dylint_testing
This crate provides convenient access to the compiletest_rs
package for testing Dylint libraries.
Specifically, this crate provides the following three functions. Note: If your test has dependencies, you must use ui_test_example
or ui_test_examples
. See the question_mark_in_expression example in this repository.
-
ui_test
- test a library on all source files in a directoryname
is the name of a Dylint library to be tested. (Often, this is the same as the package name.)src_base
is a directory containing:- source files on which to test the library (
.rs
files), and - the output those files should produce (
.stderr
files).
- source files on which to test the library (
-
ui_test_example
- test a library on one example targetname
is the name of a Dylint library to be tested.example
is an example target on which to test the library.
-
ui_test_examples
- test a library on all example targetsname
is the name of a Dylint library to be tested.
For most situations, you can add the following to your library's lib.rs
file:
And include one or more .rs
and .stderr
files in a ui
directory alongside your library's src
directory. See the examples in this repository.
Updating .stderr
files
If the standard error that results from running your .rs
file differs from the contents of your .stderr
file, compiletest_rs
will produce a report like the following:
diff of stderr:
error: calling ` set_var` in a test could affect the outcome of other tests
-/main.rs:8:5
|
LL | set_var;
= note: `-D nonreentrant-function-in-test` implied by `-D warnings`
-error: aborting due to previous error
+error: calling ` set_var` in a test could affect the outcome of other tests
+ -/main.rs:23:9
+ |
+LL | set_var;
+ | ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
+
+error: aborting due to 2 previous errors
The actual stderr differed from the expected stderr.
Actual stderr saved to ...
The meaning of each line is as follows:
- A line beginning with a plus (
+
) is in the actual standard error, but not in your.stderr
file. - A line beginning with a minus (
-
) is in your.stderr
file, but not in the actual standard error. - A line beginning with a space (
.stderr
file, and is provided for context. - All other lines (e.g.,
diff of stderr:
) containcompiletest_rs
messages.
Note: In the actual standard error, a blank line usually follows the error: aborting due to N previous errors
line. So a correct .stderr
file will typically contain one blank line at the end.
In general, it is not too hard to update a .stderr
file by hand. However, the compiletest_rs
report should contain a line of the form Actual stderr saved to PATH
. Copying PATH
to your .stderr
file should update it completely.
Additional documentation on compiletest_rs
can be found in its repository.