A :class:`VUnit <vunit.ui.VUnit>` object can be created from command line arguments by using the :meth:`from_argv <vunit.ui.VUnit.from_argv>` method effectively creating a custom command line tool for running tests in the user project. Source files and libraries are added to the project by using methods on the VUnit object. The configuration is followed by a call to the :meth:`main <vunit.ui.VUnit.main>` method which will execute the function specified by the command line arguments and exit the script. The added source files are automatically scanned for test cases.
.. argparse:: :ref: vunit.vunit_cli._parser_for_documentation :prog: run.py
The :vunit_example:`VHDL User Guide Example <vhdl/user_guide/>` can be run to produce the following output:
> python run.py -l
lib.tb_example.all
lib.tb_example_many.test_pass
lib.tb_example_many.test_fail
Listed 3 tests
> python run.py -v lib.tb_example*
Running test: lib.tb_example.all
Running test: lib.tb_example_many.test_pass
Running test: lib.tb_example_many.test_fail
Running 3 tests
running lib.tb_example.all
Hello World!
pass( P=1 S=0 F=0 T=3) lib.tb_example.all (0.1 seconds)
running lib.tb_example.test_pass
This will pass
pass (P=2 S=0 F=0 T=3) lib.tb_example_many.test_pass (0.1 seconds)
running lib.tb_example.test_fail
Error: It fails
fail (P=2 S=0 F=1 T=3) lib.tb_example_many.test_fail (0.1 seconds)
==== Summary =========================================
pass lib.tb_example.all (0.1 seconds)
pass lib.tb_example_many.test_pass (0.1 seconds)
fail lib.tb_example_many.test_fail (0.1 seconds)
======================================================
pass 2 of 3
fail 1 of 3
======================================================
Total time was 0.3 seconds
Elapsed time was 0.3 seconds
======================================================
Some failed!
> python run.py -v lib.tb_example.all
Running test: lib.tb_example.all
Running 1 tests
Starting lib.tb_example.all
Hello world!
pass (P=1 S=0 F=0 T=1) lib.tb_example.all (0.1 seconds)
==== Summary ==========================
pass lib.tb_example.all (0.9 seconds)
=======================================
pass 1 of 1
=======================================
Total time was 0.9 seconds
Elapsed time was 1.2 seconds
=======================================
All passed!
Sometimes the textual error messages and logs are not enough to
pinpoint the error and a test case needs to be opened in the GUI for
visual debugging using single stepping, breakpoints and wave form
viewing. VUnit makes it easy to open a test case in the GUI by having
a -g/--gui
command line flag:
> python run.py --gui my_test_case &
This launches a simulator GUI window with the top level for the selected test case loaded and ready to run. Depending on the simulator a help text is printed were a few TCL functions are pre-defined:
# vunit_help
# - Prints this help
# vunit_load [vsim_extra_args]
# - Load design with correct generics for the test
# - Optional first argument are passed as extra flags to vsim
# vunit_user_init
# - Re-runs the user defined init file
# vunit_run
# - Run test, must do vunit_load first
# vunit_compile
# - Recompiles the source files
# vunit_restart
# - Recompiles the source files
# - and re-runs the simulation if the compile was successful
The test bench has already been loaded with the vunit_load
command. Breakpoints can now be set and signals added to the log or to
the waveform viewer manually by the user. The test case is then run
using the vunit_run
command. Recompilation can be performed
without closing the GUI by running vunit_compile
. It is also
possible to perform run.py
with the --compile
flag in a
separate terminal.
VUnit creates a separate output directory for each test to provide
isolation. The test output paths are located under
OUTPUT_PATH/test_output/
. The test names have been washed of any
unsuitable characters and a hash has been added as a suffix to ensure
uniqueness.
On Windows the paths can be shortened to avoid path length limitations. This behavior can be controlled by setting the relevant :ref:`environment variables <test_output_envs>`.
To get the exact test name to test output path mapping the file
OUTPUT_PATH/test_output/test_name_to_path_mapping.txt
can be used.
Each line contains a test output path followed by a space seperator
and then a test name.
Note
When using the run_all_in_same_sim
pragma all tests within the
test bench share the same output folder named after the test bench.
VUnit automatically detects which simulators are available on the
PATH
environment variable and by default selects the first one
found. For people who have multiple simulators installed the
VUNIT_SIMULATOR
environment variable can be set to one of
activehdl
, rivierapro
, ghdl
or modelsim
to specify
which simulator to use. modelsim
is used for both ModelSim and
Questa as VUnit handles these simulators identically.
In addition to VUnit scanning the PATH
the simulator executable
path can be explicitly configured by setting a
VUNIT_<SIMULATOR_NAME>_PATH
environment variable.
VUNIT_GHDL_PATH=/opt/ghdl/bin
VUNIT_MODELSIM_INI
By default VUnit copies the modelsim.ini file from the tool install folder as a starting point. Setting this environment variable selects another modelsim.ini file as the starting point allowing the user to customize it.
VUNIT_SHORT_TEST_OUTPUT_PATHS
Unfortunately file system paths are still practically limited to 260 characters on Windows. VUnit tries to limit the length of the test output paths on Windows to avoid this limitation but still includes as much of the test name name as possible leaving a margin of 100 characters. VUnit however cannot forsee user specific test output file lengths and this environment variable can be set to minimize output path lengths on Windows. On other operating systems this limitation is not relevant.VUNIT_TEST_OUTPUT_PATH_MARGIN
Can be used to change the test output path margin on Windows. By default the test output path is shortened to allow a 100 character margin.
The VHDL revision can be specified through the :ref:`python_interface`
(see :class:`vunit.ui.VUnit`).
Alternatively, environment variable VUNIT_VHDL_STANDARD
can be set to
93``|``1993
, 02``|``2002
, 08``|``2008
(default) or 19``|``2019
.
Important
Note that VHDL revision 2019 is unsupported by most vendors, and support of VHDL 2008 features is uneven. Check the documentation of the simulator before using features requiring revisions equal or newer than 2008.
VUnit supports exporting project information through the --export-json
command
line argument. A JSON file is written containing the list of all files
added to the project as well as a list of all tests. Each test has a
mapping to its source code location.
The feature can be used for IDE-integration where the IDE can know the path to all files, the library mapping of files and the source code location of all tests.
The JSON export file has three top level values:
export_format_version
: The semantic version of the formatfiles
: List of project files. Each file item hasfile_name
andlibrary_name
.tests
: List of tests. Each test hasattributes
,location
andname
information. Attributes is the list of test attributes. Thelocation
contains the file name as well as the offset and length in characters of the symbol that defines the test.name
is the name of the test.
{
"export_format_version": {
"major": 1,
"minor": 0,
"patch": 0
},
"files": [
{
"library_name": "lib",
"file_name": "tb_example_many.vhd"
},
{
"library_name": "lib",
"file_name": "tb_example.vhd"
}
],
"tests": [
{
"attributes": {},
"location": {
"file_name": "tb_example_many.vhd",
"length": 9,
"offset": 556
},
"name": "lib.tb_example_many.test_pass"
},
{
"attributes": {},
"location": {
"file_name": "tb_example_many.vhd",
"length": 9,
"offset": 624
},
"name": "lib.tb_example_many.test_fail"
},
{
"attributes": {
".attr": null
},
"location": {
"file_name": "tb_example.vhd",
"length": 18,
"offset": 465
},
"name": "lib.tb_example.all"
}
]
}
Note
Several tests may map to the same source code location if the user created multiple :ref:`configurations <configurations>` of the same basic tests.