Open CASCADE Technology  7.2.0
Automated Testing System


This document provides OCCT developers and contributors with an overview and practical guidelines for work with OCCT automatic testing system.

Reading the Introduction should be sufficient for developers to use the test system to control non-regression of the modifications they implement in OCCT. Other sections provide a more in-depth description of the test system, required for modifying the tests and adding new test cases.

Basic Information

OCCT automatic testing system is organized around DRAW Test Harness, a console application based on Tcl (a scripting language) interpreter extended by OCCT-related commands.

Standard OCCT tests are included with OCCT sources and are located in subdirectory tests of the OCCT root folder. Other test folders can be included in the test system, e.g. for testing applications based on OCCT.

The tests are organized in three levels:

  • Group: a group of related test grids, usually testing a particular OCCT functionality (e.g. blend);
  • Grid: a set of test cases within a group, usually aimed at testing some particular aspect or mode of execution of the relevant functionality (e.g. buildevol);
  • Test case: a script implementing an individual test (e.g. K4).

See Test Groups chapter for the current list of available test groups and grids.

Many tests involve data files (typically CAD models) which are located separately and (except a few) are not included with OCCT code. These tests will be skipped if data files are not available.

Intended Use of Automatic Tests

Each modification made in OCCT code must be checked for non-regression by running the whole set of tests. The developer who makes the modification is responsible for running and ensuring non-regression for the tests available to him.

Note that many tests are based on data files that are confidential and thus available only at OPEN CASCADE. The official certification testing of each change before its integration to master branch of official OCCT Git repository (and finally to the official release) is performed by OPEN CASCADE to ensure non-regression on all existing test cases and supported platforms.

Each new non-trivial modification (improvement, bug fix, new feature) in OCCT should be accompanied by a relevant test case suitable for verifying that modification. This test case is to be added by the developer who provides the modification.

If a modification affects the result of an existing test case, either the modification should be corrected (if it causes regression) or the affected test cases should be updated to account for the modification.

The modifications made in the OCCT code and related test scripts should be included in the same integration to the master branch.

Quick Start


Before running tests, make sure to define environment variable CSF_TestDataPath pointing to the directory containing test data files.

For this it is recommended to add a file DrawAppliInit in the directory which is current at the moment of starting DRAWEXE (normally it is OCCT root directory, $CASROOT ). This file is evaluated automatically at the DRAW start.

Example (Windows)

1 set env(CSF_TestDataPath) $env(CSF_TestDataPath)\;d:/occt/test-data

Note that variable CSF_TestDataPath is set to default value at DRAW start, pointing at the folder $CASROOT/data. In this example, subdirectory d:/occt/test-data is added to this path. Similar code could be used on Linux and Mac OS X except that on non-Windows platforms colon ":" should be used as path separator instead of semicolon ";".

All tests are run from DRAW command prompt (run draw.bat or to start it).

Running Tests

To run all tests, type command testgrid


Draw[]> testgrid

To run only a subset of test cases, give masks for group, grid, and test case names to be executed. Each argument is a list of file masks separated with commas or spaces; by default "*" is assumed.


Draw[]> testgrid bugs caf,moddata*,xde

As the tests progress, the result of each test case is reported. At the end of the log a summary of test cases is output, including the list of detected regressions and improvements, if any.


1 Tests summary
3 CASE 3rdparty export A1: OK
4 ...
5 CASE pipe standard B1: BAD (known problem)
6 CASE pipe standard C1: OK
7 No regressions
8 Total cases: 208 BAD, 31 SKIPPED, 3 IMPROVEMENT, 1791 OK
9 Elapsed time: 1 Hours 14 Minutes 33.7384512019 Seconds
10 Detailed logs are saved in D:/occt/results_2012-06-04T0919

The tests are considered as non-regressive if only OK, BAD (i.e. known problem), and SKIPPED (i.e. not executed, typically because of lack of a data file) statuses are reported. See Interpretation of test results for details.

The results and detailed logs of the tests are saved by default to a new subdirectory of the subdirectory results in the current folder, whose name is generated automatically using the current date and time, prefixed by Git branch name (if Git is available and current sources are managed by Git). If necessary, a non-default output directory can be specified using option -outdir followed by a path to the directory. This directory should be new or empty; use option -overwrite to allow writing results in the existing non-empty directory.


Draw[]> testgrid -outdir d:/occt/last_results -overwrite

In the output directory, a cumulative HTML report summary.html provides links to reports on each test case. An additional report in JUnit-style XML format can be output for use in Jenkins or other continuous integration system.

To re-run the test cases, which were detected as regressions on the previous run, option -regress dirname should be used. dirname is a path to the directory containing the results of the previous run. Only the test cases with FAILED and IMPROVEMENT statuses will be tested.


Draw[]> testgrid -regress d:/occt/last_results

Type help testgrid in DRAW prompt to get help on options supported by testgrid command:

Draw[3]> help testgrid
testgrid: Run all tests, or specified group, or one grid
Use: testgrid [groupmask [gridmask [casemask]]] [options...]
Allowed options are:
-parallel N: run N parallel processes (default is number of CPUs, 0 to disable)
-refresh N: save summary logs every N seconds (default 60, minimal 1, 0 to disable)
-outdir dirname: set log directory (should be empty or non-existing)
-overwrite: force writing logs in existing non-empty directory
-xml filename: write XML report for Jenkins (in JUnit-like format)
-beep: play sound signal at the end of the tests
-regress dirname: re-run only a set of tests that have been detected as regressions on the previous run.
Here "dirname" is a path to the directory containing the results of the previous run.
Groups, grids, and test cases to be executed can be specified by the list of file
masks separated by spaces or commas; default is all (*).

Running a Single Test

To run a single test, type command test followed by names of group, grid, and test case.


1 Draw[1]> test blend simple A1
2 CASE blend simple A1: OK
3 Draw[2]>

Note that normally an intermediate output of the script is not shown. The detailed log of the test can be obtained after the test execution by running command "dlog get".

To see intermediate commands and their output during the test execution, add one more argument "echo" at the end of the command line. Note that with this option the log is not collected and summary is not produced.

Type help test in DRAW prompt to get help on options supported by test command:

Draw[3]> help test
test: Run specified test case
Use: test group grid casename [options...]
Allowed options are:
-echo: all commands and results are echoed immediately,
but log is not saved and summary is not produced
It is also possible to use "1" instead of "-echo"
If echo is OFF, log is stored in memory and only summary
is output (the log can be obtained with command "dlog get")
-outfile filename: set log file (should be non-existing),
it is possible to save log file in text file or
in html file(with snapshot), for that "filename"
should have ".html" extension
-overwrite: force writing log in existing file
-beep: play sound signal at the end of the test
-errors: show all lines from the log report that are recognized as errors
This key will be ignored if the "-echo" key is already set.

Creating a New Test

The detailed rules of creation of new tests are given in Creation and modification of tests chapter. The following short description covers the most typical situations:

Use prefix bug followed by Mantis issue ID and, if necessary, additional suffixes, for naming the test script, data files, and DRAW commands specific for this test case.

  1. If the test requires C++ code, add it as new DRAW command(s) in one of files in QABugs package.
  2. Add script(s) for the test case in the subfolder corresponding to the relevant OCCT module of the group bugs ($CASROOT/tests/bugs). See the correspondence map.
  3. In the test script:
    • Load all necessary DRAW modules by command pload.
    • Use command locate_data_file to get a path to data files used by test script. (Make sure to have this command not inside catch statement if it is used.)
    • Use DRAW commands to reproduce the tested situation.
    • Make sure that in case of failure the test produces a message containing word "Error" or other recognized by the test system as error (add new error patterns in file parse.rules if necessary).
    • If the test case reports error due to an existing problem and the fix is not available, add TODO statement for each error to mark it as a known problem. The TODO statements must be specific so as to match the actually generated messages but not all similar errors.
    • To check expected output which should be obtained as the test result, add REQUIRED statement for each line of output to mark it as required.
    • If the test case produces error messages (contained in parse.rules), which are expected in that test and should not be considered as its failure (e.g. test for checkshape command), add REQUIRED statement for each error to mark it as required output.
  4. If the test uses data file(s) that are not yet present in the test database, it is possible to put them to (sub)directory pointed out by CSF_TestDataPath variable for running test. The files should be attached to the Mantis issue corresponding to the tested modification.
  5. Check that the test case runs as expected (test for fix: OK with the fix, FAILED without the fix; test for existing problem: BAD), and integrate it to the Git branch created for the issue.


  • Added files:
git status -short
A tests/bugs/heal/data/bug210_a.brep
A tests/bugs/heal/data/bug210_b.brep
A tests/bugs/heal/bug210_1
A tests/bugs/heal/bug210_2
  • Test script
1 puts "OCC210 (case 1): Improve FixShape for touching wires"
3 restore [locate_data_file bug210_a.brep] a
5 fixshape result a 0.01 0.01
6 checkshape result

Organization of Test Scripts

General Layout

Standard OCCT tests are located in subdirectory tests of the OCCT root folder ($CASROOT).

Additional test folders can be added to the test system by defining environment variable CSF_TestScriptsPath. This should be list of paths separated by semicolons (*;*) on Windows or colons (*:*) on Linux or Mac. Upon DRAW launch, path to tests subfolder of OCCT is added at the end of this variable automatically.

Each test folder is expected to contain:

  • Optional file parse.rules defining patterns for interpretation of test results, common for all groups in this folder
  • One or several test group directories.

Each group directory contains:

  • File grids.list that identifies this test group and defines list of test grids in it.
  • Test grids (sub-directories), each containing set of scripts for test cases, and optional files cases.list, parse.rules, begin and end.
  • Optional sub-directory data

By convention, names of test groups, grids, and cases should contain no spaces and be lower-case. The names begin, end, data, parse.rules, grids.list and cases.list are reserved.

General layout of test scripts is shown in Figure 1.

Layout of tests folder

Test Groups

Group Names

The names of directories of test groups containing systematic test grids correspond to the functionality tested by each group.



Test group bugs is used to collect the tests coming from bug reports. Group demo collects tests of the test system, DRAW, samples, etc.

File "grids.list"

This test group contains file grids.list, which defines an ordered list of grids in this group in the following format:

001 gridname1
002 gridname2
NNN gridnameN


001 basic
002 advanced

File "begin"

This file is a Tcl script. It is executed before every test in the current group. Usually it loads necessary Draw commands, sets common parameters and defines additional Tcl functions used in test scripts.


1 pload TOPTEST ;# load topological command
2 set cpulimit 300 ;# set maximum time allowed for script execution

File "end"

This file is a TCL script. It is executed after every test in the current group. Usually it checks the results of script work, makes a snap-shot of the viewer and writes TEST COMPLETED to the output.

Note: TEST COMPLETED string should be present in the output to indicate that the test is finished without crash.

See Creation and modification of tests chapter for more information.


if { [isdraw result] } {
checkshape result
} else {
puts "Error: The result shape can not be built"

File "parse.rules"

The test group may contain parse.rules file. This file defines patterns used for analysis of the test execution log and deciding the status of the test run.

Each line in the file should specify a status (single word), followed by a regular expression delimited by slashes (*/*) that will be matched against lines in the test output log to check if it corresponds to this status.

The regular expressions should follow Tcl syntax, with a special exception that "\b" is considered as word limit (Perl-style), in addition to "\y" used in Tcl.

The rest of the line can contain a comment message, which will be added to the test report when this status is detected.


FAILED /\b[Ee]xception\b/ exception
FAILED /\bError\b/ error
SKIPPED /Cannot open file for reading/ data file is missing
SKIPPED /Could not read file .*, abandon/ data file is missing

Lines starting with a *#* character and blank lines are ignored to allow comments and spacing.

See Interpretation of test results chapter for details.

If a line matches several rules, the first one applies. Rules defined in the grid are checked first, then rules in the group, then rules in the test root directory. This allows defining some rules on the grid level with status IGNORE to ignore messages that would otherwise be treated as errors due to the group level rules.


1 FAILED /\\bFaulty\\b/ bad shape
2 IGNORE /^Error [23]d = [\d.-]+/ debug output of blend command
3 IGNORE /^Tcl Exception: tolerance ang : [\d.-]+/ blend failure

Directory "data"

The test group may contain subdirectory data, where test scripts shared by different test grids can be put. See also Directory data.

Test Grids

Grid Names

The folder of a test group can have several sub-directories (Grid 1… Grid N) defining test grids. Each directory contains a set of related test cases. The name of a directory should correspond to its contents.



Here caf is the name of the test group and basic, bugs, presentation, etc. are the names of grids.

File "begin"

This file is a TCL script executed before every test in the current grid.

Usually it sets variables specific for the current grid.


1 set command bopfuse ;# command tested in this grid

File "end"

This file is a TCL script executed after every test in current grid.

Usually it executes a specific sequence of commands common for all tests in the grid.


1 vdump $imagedir/${casename}.png ;# makes a snap-shot of AIS viewer

File "cases.list"

The grid directory can contain an optional file cases.list defining an alternative location of the test cases. This file should contain a single line defining the relative path to the collection of test cases.



This option is used for creation of several grids of tests with the same data files and operations but performed with differing parameters. The common scripts are usually located place in the common subdirectory of the test group, data/simple for example.

If file cases.list exists, the grid directory should not contain any test cases. The specific parameters and pre- and post-processing commands for test execution in this grid should be defined in the files begin and end.

Directory "data"

The test grid may contain subdirectory data, containing data files used in tests (BREP, IGES, STEP, etc.) of this grid.

Test Cases

The test case is a TCL script, which performs some operations using DRAW commands and produces meaningful messages that can be used to check the validity of the result.


1 pcylinder c1 10 20 ;# create first cylinder
2 pcylinder c2 5 20 ;# create second cylinder
3 ttranslate c2 5 0 10 ;# translate second cylinder to x,y,z
4 bsection result c1 c2 ;# create a section of two cylinders
5 checksection result ;# will output error message if result is bad

The test case can have any name (except for the reserved names begin, end, data, cases.list and parse.rules). For systematic grids it is usually a capital English letter followed by a number.



Such naming facilitates compact representation of tests execution results in tabular format within HTML reports.

Creation And Modification Of Tests

This section describes how to add new tests and update existing ones.

Choosing Group, Grid, and Test Case Name

The new tests are usually added in the frame of processing issues in OCCT Mantis tracker. Such tests in general should be added to group bugs, in the grid corresponding to the affected OCCT functionality. See Mapping of OCCT functionality to grid names in group bugs.

New grids can be added as necessary to contain tests for the functionality not yet covered by existing test grids. The test case name in the bugs group should be prefixed by the ID of the corresponding issue in Mantis (without leading zeroes) with prefix bug. It is recommended to add a suffix providing a hint on the tested situation. If more than one test is added for a bug, they should be distinguished by suffixes; either meaningful or just ordinal numbers.


1 bug12345_coaxial
2 bug12345_orthogonal_1
3 bug12345_orthogonal_2

If the new test corresponds to a functionality already covered by the existing systematic test grid (e.g. group mesh for BRepMesh issues), this test can be added (or moved later by OCC team) to that grid.

Adding Data Files Required for a Test

It is advisable to make self-contained test scripts whenever possible, so as they could be used in the environments where data files are not available. For that simple geometric objects and shapes can be created using DRAW commands in the test script itself.

If the test requires a data file, it should be put to the directory listed in environment variable CSF_TestDataPath. Alternatively, it can be put to subdirectory data of the test grid. It is recommended to prefix the data file with the corresponding issue id prefixed by bug, e.g. bug12345_face1.brep, to avoid possible conflicts with names of existing data files.

Note that when the test is integrated to the master branch, OCC team will move the data file to the data files repository, to keep OCCT sources repository clean from data files.

When you prepare a test script, try to minimize the size of involved data model. For instance, if the problem detected on a big shape can be reproduced on a single face extracted from that shape, use only that face in the test.

Adding new DRAW commands

If the test cannot be implemented using available DRAW commands, consider the following possibilities:

  • If the existing DRAW command can be extended to enable possibility required for a test in a natural way (e.g. by adding an option to activate a specific mode of the algorithm), this way is recommended. This change should be appropriately documented in a relevant Mantis issue.
  • If the new command is needed to access OCCT functionality not exposed to DRAW previously, and this command can be potentially reused (for other tests), it should be added to the package where similar commands are implemented (use getsource DRAW command to get the package name). The name and arguments of the new command should be chosen to keep similarity with the existing commands. This change should be documented in a relevant Mantis issue.
  • Otherwise the new command implementing the actions needed for this particular test should be added in QABugs package. The command name should be formed by the Mantis issue ID prefixed by bug, e.g. bug12345.

Note that a DRAW command is expected to return 0 in case of a normal completion, and 1 (Tcl exception) if it is incorrectly used (e.g. a wrong number of input arguments). Thus if the new command needs to report a test error, this should be done by outputting an appropriate error message rather than by returning a non-zero value. File names must be encoded in the script rather than in the DRAW command and passed to the DRAW command as an argument.

Script Implementation

The test should run commands necessary to perform the tested operations, in general assuming a clean DRAW session. The required DRAW modules should be loaded by pload command, if it is not done by begin script. The messages produced by commands in a standard output should include identifiable messages on the discovered problems if any.

Usually the script represents a set of commands that a person would run interactively to perform the operation and see its results, with additional comments to explain what happens.


# Simple test of fusing box and sphere
box b 10 10 10
sphere s 5
bfuse result b s
checkshape result

Make sure that file parse.rules in the grid or group directory contains a regular expression to catch possible messages indicating the failure of the test.

For instance, for catching errors reported by checkshape command relevant grids define a rule to recognize its report by the word Faulty:

FAILED /\bFaulty\b/ bad shape

For the messages generated in the script it is recommended to use the word 'Error' in the error message.


set expected_length 11
if { [expr $actual_length - $expected_length] > 0.001 } {
puts "Error: The length of the edge should be $expected_length"

At the end, the test script should output TEST COMPLETED string to mark a successful completion of the script. This is often done by the end script in the grid.

When the test script requires a data file, use Tcl procedure locate_data_file to get a path to it, instead of putting the path explicitly. This will allow easy move of the data file from OCCT sources repository to the data files repository without the need to update the test script.


stepread [locate_data_file CAROSKI_COUPELLE.step] a *

When the test needs to produce some snapshots or other artefacts, use Tcl variable imagedir as the location where such files should be put.

  • Command testgrid sets this variable to the subdirectory of the results folder corresponding to the grid.
  • Command test by default creates a dedicated temporary directory in the system temporary folder (normally the one specified by environment variable TempDir, TEMP, or TMP) for each execution, and sets imagedir to that location.

However if variable imagedir is defined on the top level of Tcl interpretor, command test will use it instead of creating a new directory.

Use Tcl variable casename to prefix all files produced by the test. This variable is set to the name of the test case.

The test system can recognize an image file (snapshot) and include it in HTML log and differences if its name starts with the name of the test case (use variable casename), optionally followed by underscore or dash and arbitrary suffix.

The image format (defined by extension) should be png.


xwd $imagedir/${casename}.png
vdisplay result; vfit
vdump $imagedir/${casename}-axo.png
vfront; vfit
vdump $imagedir/${casename}-front.png

would produce:


Note that OCCT must be built with FreeImage support to be able to produce usable images.

Other Tcl variables defined during the test execution are:

  • groupname: name of the test group;
  • gridname: name of the test grid;
  • dirname: path to the root directory of the current set of test scripts.

In order to ensure that the test works as expected in different environments, observe the following additional rules:

  • Avoid using external commands such as grep, rm, etc., as these commands can be absent on another system (e.g. on Windows); use facilities provided by Tcl instead.
  • Do not put call to locate_data_file in catch statement – this can prevent correct interpretation of the missing data file by the test system.
  • Do not use commands decho and dlog in the test script, to avoid interference with use of these commands by the test system.

Interpretation of test results

The result of the test is evaluated by checking its output against patterns defined in the files parse.rules of the grid and group.

The OCCT test system recognizes five statuses of the test execution:

  • SKIPPED: reported if a line matching SKIPPED pattern is found (prior to any FAILED pattern). This indicates that the test cannot be run in the current environment; the most typical case is the absence of the required data file.
  • FAILED: reported if a line matching pattern with status FAILED is found (unless it is masked by the preceding IGNORE pattern or a TODO or REQUIRED statement), or if message TEST COMPLETED or at least one of REQUIRED patterns is not found. This indicates that the test has produced a bad or unexpected result, and usually means a regression.
  • BAD: reported if the test script output contains one or several TODO statements and the corresponding number of matching lines in the log. This indicates a known problem. The lines matching TODO statements are not checked against other patterns and thus will not cause a FAILED status.
  • IMPROVEMENT: reported if the test script output contains a TODO statement for which no corresponding line is found. This is a possible indication of improvement (a known problem has disappeared).
  • OK: reported if none of the above statuses have been assigned. This means that the test has passed without problems.

Other statuses can be specified in parse.rules files, these will be classified as FAILED.

For integration of the change to OCCT repository, all tests should return either OK or BAD status. The new test created for an unsolved problem should return BAD. The new test created for a fixed problem should return FAILED without the fix, and OK with the fix.

Marking BAD cases

If the test produces an invalid result at a certain moment then the corresponding bug should be created in the OCCT issue tracker located at, and the problem should be marked as TODO in the test script.

The following statement should be added to such a test script:

puts "TODO BugNumber ListOfPlatforms: RegularExpression"


  • BugNumber is the bug ID in the tracker. For example: #12345.
  • ListOfPlatforms is a list of platforms, at which the bug is reproduced (Linux, Windows, MacOS, or All). Note that the platform name is custom for the OCCT test system; Use procedure checkplatform to get the platform name.


Draw[2]> checkplatform
  • RegularExpression is a regular expression, which should be matched against the line indicating the problem in the script output.


puts "TODO #22622 Mandriva2008: Abort .* an exception was raised"

The parser checks the test output and if an output line matches the RegularExpression then it will be assigned a BAD status instead of FAILED.

A separate TODO line must be added for each output line matching an error expression to mark the test as BAD. If not all TODO messages are found in the test log, the test will be considered as possible improvement.

To mark the test as BAD for an incomplete case (when the final TEST COMPLETE message is missing) the expression TEST INCOMPLETE should be used instead of the regular expression.


puts "TODO OCC22817 All: exception.+There are no suitable edges"
puts "TODO OCC22817 All: \\*\\* Exception \\*\\*"

Marking required output

To check the obtained test output matches the expected results considered correct, add REQUIRED statement for each specific message. For that, the following statement should be added to the corresponding test script:

puts "REQUIRED ListOfPlatforms: RegularExpression"

Here ListOfPlatforms and RegularExpression have the same meaning as in TODO statements described above.

The REQUIRED statement can also be used to mask the message that would normally be interpreted as error (according to the rules defined in parse.rules) but should not be considered as such within the current test.


puts "REQUIRED Linux: Faulty shapes in variables faulty_1 to faulty_5"

This statement notifies test system that errors reported by checkshape command are expected in that test case, and test should be considered as OK if this message appears, despite of presence of general rule stating that 'Faulty' signals failure.

If output does not contain required statement, test case will be marked as FAILED.

Advanced Use

Running Tests on Older Versions of OCCT

Sometimes it might be necessary to run tests on the previous versions of OCCT (<= 6.5.4) that do not include this test system. This can be done by adding DRAW configuration file DrawAppliInit in the directory, which is current by the moment of DRAW start-up, to load test commands and to define the necessary environment.

Note: in OCCT 6.5.3, file DrawAppliInit already exists in $CASROOT/src/DrawResources, new commands should be added to this file instead of a new one in the current directory.

For example, let us assume that d:/occt contains an up-to-date version of OCCT sources with tests, and the test data archive is unpacked to d:/test-data):

set env(CASROOT) d:/occt
set env(CSF_TestScriptsPath) $env(CASROOT)/tests
source $env(CASROOT)/src/DrawResources/TestCommands.tcl
set env(CSF_TestDataPath) $env(CASROOT)/data;d:/test-data

Note that on older versions of OCCT the tests are run in compatibility mode and thus not all output of the test command can be captured; this can lead to absence of some error messages (can be reported as either a failure or an improvement).

Adding custom tests

You can extend the test system by adding your own tests. For that it is necessary to add paths to the directory where these tests are located, and one or more additional data directories, to the environment variables CSF_TestScriptsPath and CSF_TestDataPath. The recommended way for doing this is using DRAW configuration file DrawAppliInit located in the directory which is current by the moment of DRAW start-up.

Use Tcl command _path_separator to insert a platform-dependent separator to the path list.

For example:

set env(CSF_TestScriptsPath) \
set env(CSF_TestDataPath) \
return ;# this is to avoid an echo of the last command above in cout

Parallel execution of tests

For better efficiency, on computers with multiple CPUs the tests can be run in parallel mode. This is default behavior for command testgrid : the tests are executed in parallel processes (their number is equal to the number of CPUs available on the system). In order to change this behavior, use option parallel followed by the number of processes to be used (1 or 0 to run sequentially).

Note that the parallel execution is only possible if Tcl extension package Thread is installed. If this package is not available, testgrid command will output a warning message.

Checking non-regression of performance, memory, and visualization

Some test results are very dependent on the characteristics of the workstation, where they are performed, and thus cannot be checked by comparison with some predefined values. These results can be checked for non-regression (after a change in OCCT code) by comparing them with the results produced by the version without this change. The most typical case is comparing the result obtained in a branch created for integration of a fix (CR***) with the results obtained on the master branch before that change is made.

OCCT test system provides a dedicated command testdiff for comparing CPU time of execution, memory usage, and images produced by the tests.

testdiff dir1 dir2 [groupname [gridname]] [options...]

Here dir1 and dir2 are directories containing logs of two test runs.

Possible options are:

  • -save <filename> – saves the resulting log in a specified file ($dir1/diff-$dir2.log by default). HTML log is saved with the same name and extension .html;
  • -status {same|ok|all} – allows filtering compared cases by their status:
    • same – only cases with same status are compared (default);
    • ok – only cases with OK status in both logs are compared;
    • all – results are compared regardless of status;
  • -verbose <level> – defines the scope of output data:
    • 1 – outputs only differences;
    • 2 – additionally outputs the list of logs and directories present in one of directories only;
    • 3 – (by default) additionally outputs progress messages;
  • -image [filename] - compare images and save the resulting log in specified file ($dir1/diffimage-$dir2.log by default)
  • -cpu [filename] - compare overall CPU and save the resulting log in specified file ($dir1/diffcpu-$dir2.log by default)
  • -memory [filename] - compare memory delta and save the resulting log in specified file ($dir1/diffmemory-$dir2.log by default)
  • -highlight_percent <value> - highlight considerable (>value in %) deviations of CPU and memory (default value is 5%)


Draw[]> testdiff results/CR12345-2012-10-10T08:00 results/master-2012-10-09T21:20

Particular tests can generate additional data that need to be compared by testdiff command. For that, for each parameter to be controlled, the test should produce the line containing keyword "COUNTER* followed by arbitrary name of the parameter, then colon and numeric value of the parameter.

Example of test code:

puts "COUNTER Memory heap usage at step 5: [meminfo h]"


Test groups


This group allows testing the interaction of OCCT and 3rdparty products.


Grid Commands Functionality
export vexport export of images to different formats
fonts vtrihedron, vcolorscale, vdrawtext display of fonts


This group allows testing blends (fillets) and related operations.


Grid Commands Functionality
simple blend fillets on simple shapes
complex blend fillets on complex shapes, non-trivial geometry
tolblend_simple tolblend, blend
buildevol buildevol
tolblend_buildvol tolblend, buildevol use of additional command tolblend
bfuseblend bfuseblend
encoderegularity encoderegularity


This group allows testing Boolean operations.

DRAW module: MODELING (packages BOPTest and BRepTest).

Grids names are based on name of the command used, with suffixes:

  • _2d – for tests operating with 2d objects (wires, wires, 3d objects, etc.);
  • _simple – for tests operating on simple shapes (boxes, cylinders, toruses, etc.);
  • _complex – for tests dealing with complex shapes.
Grid Commands Functionality
bcommon_2d bcommon Common operation (old algorithm), 2d
bcommon_complex bcommon Common operation (old algorithm), complex shapes
bcommon_simple bcommon Common operation (old algorithm), simple shapes
bcut_2d bcut Cut operation (old algorithm), 2d
bcut_complex bcut Cut operation (old algorithm), complex shapes
bcut_simple bcut Cut operation (old algorithm), simple shapes
bcutblend bcutblend
bfuse_2d bfuse Fuse operation (old algorithm), 2d
bfuse_complex bfuse Fuse operation (old algorithm), complex shapes
bfuse_simple bfuse Fuse operation (old algorithm), simple shapes
bopcommon_2d bopcommon Common operation, 2d
bopcommon_complex bopcommon Common operation, complex shapes
bopcommon_simple bopcommon Common operation, simple shapes
bopcut_2d bopcut Cut operation, 2d
bopcut_complex bopcut Cut operation, complex shapes
bopcut_simple bopcut Cut operation, simple shapes
bopfuse_2d bopfuse Fuse operation, 2d
bopfuse_complex bopfuse Fuse operation, complex shapes
bopfuse_simple bopfuse Fuse operation, simple shapes
bopsection bopsection Section
boptuc_2d boptuc
boptuc_complex boptuc
boptuc_simple boptuc
bsection bsection Section (old algorithm)


This group allows testing cases coming from Mantis issues.

The grids are organized following OCCT module and category set for the issue in the Mantis tracker. See Mapping of OCCT functionality to grid names in group bugs chapter for details.


This group allows testing OCAF functionality.


Grid Commands Functionality
basic Basic attributes
bugs Saving and restoring of document
driver OCAF drivers
named_shape TNaming_NamedShape attribute
presentation AISPresentation attributes
tree Tree construction attributes
xlink XLink attributes


This group allows testing chamfer operations.


The test grid name is constructed depending on the type of the tested chamfers. Additional suffix _complex is used for test cases involving complex geometry (e.g. intersections of edges forming a chamfer); suffix _sequence is used for grids where chamfers are computed sequentially.

Grid Commands Functionality
equal_dist Equal distances from edge
equal_dist_complex Equal distances from edge, complex shapes
equal_dist_sequence Equal distances from edge, sequential operations
dist_dist Two distances from edge
dist_dist_complex Two distances from edge, complex shapes
dist_dist_sequence Two distances from edge, sequential operations
dist_angle Distance from edge and given angle
dist_angle_complex Distance from edge and given angle
dist_angle_sequence Distance from edge and given angle


This group allows demonstrating how testing cases are created, and testing DRAW commands and the test system as a whole.

Grid Commands Functionality
draw getsource, restore Basic DRAW commands
testsystem Testing system
samples OCCT samples


This group allows testing draft operations.


Grid Commands Functionality
Angle depouille Drafts with angle (inclined walls)


This group allows testing creation of features on a shape.

DRAW module: MODELING (package BRepTest).

Grid Commands Functionality


This group allows testing the functionality provided by ShapeHealing toolkit.


Grid Commands Functionality
fix_shape fixshape Shape healing
fix_gaps fixwgaps Fixing gaps between edges on a wire
same_parameter sameparameter Fixing non-sameparameter edges
same_parameter_locked sameparameter Fixing non-sameparameter edges
fix_face_size DT_ApplySeq Removal of small faces
elementary_to_revolution DT_ApplySeq Conversion of elementary surfaces to revolution
direct_faces directfaces Correction of axis of elementary surfaces
drop_small_edges fixsmall Removal of small edges
split_angle DT_SplitAngle Splitting periodic surfaces by angle
split_angle_advanced DT_SplitAngle Splitting periodic surfaces by angle
split_angle_standard DT_SplitAngle Splitting periodic surfaces by angle
split_closed_faces DT_ClosedSplit Splitting of closed faces
surface_to_bspline DT_ToBspl Conversion of surfaces to b-splines
surface_to_bezier DT_ShapeConvert Conversion of surfaces to bezier
split_continuity DT_ShapeDivide Split surfaces by continuity criterion
split_continuity_advanced DT_ShapeDivide Split surfaces by continuity criterion
split_continuity_standard DT_ShapeDivide Split surfaces by continuity criterion
surface_to_revolution_advanced DT_ShapeConvertRev Convert elementary surfaces to revolutions, complex cases
surface_to_revolution_standard DT_ShapeConvertRev Convert elementary surfaces to revolutions, simple cases
update_tolerance_locked updatetolerance Update the tolerance of shape so that it satisfy the rule: toler(face)<=toler(edge)<=toler(vertex)


This group allows testing shape tessellation (BRepMesh) and shading.

DRAW modules: MODELING (package MeshTest), VISUALIZATION (package ViewerTest)

Grid Commands Functionality
advanced_shading vdisplay Shading, complex shapes
standard_shading vdisplay Shading, simple shapes
advanced_mesh mesh Meshing of complex shapes
standard_mesh mesh Meshing of simple shapes
advanced_incmesh incmesh Meshing of complex shapes
standard_incmesh incmesh Meshing of simple shapes
advanced_incmesh_parallel incmesh Meshing of complex shapes, parallel mode
standard_incmesh_parallel incmesh Meshing of simple shapes, parallel mode


This group allows testing creation of simple surfaces.

DRAW module: MODELING (package BRepTest)

Grid Commands Functionality
after_trim mkface
after_offset mkface
after_extsurf_and_offset mkface
after_extsurf_and_trim mkface
after_revsurf_and_offset mkface
mkplane mkplane


This group allows testing normal projection of edges and wires onto a face.

DRAW module: MODELING (package BRepTest)

Grid Commands Functionality
Base nproject


This group allows testing offset functionality for curves and surfaces.

DRAW module: MODELING (package BRepTest)

Grid Commands Functionality
compshape offsetcompshape Offset of shapes with removal of some faces
faces_type_a offsetparameter, offsetload, offsetperform Offset on a subset of faces with a fillet
faces_type_i offsetparameter, offsetload, offsetperform Offset on a subset of faces with a sharp edge
shape_type_a offsetparameter, offsetload, offsetperform Offset on a whole shape with a fillet
shape_type_i offsetparameter, offsetload, offsetperform Offset on a whole shape with a fillet
shape offsetshape
wire_closed_outside_0_005, wire_closed_outside_0_025, wire_closed_outside_0_075, wire_closed_inside_0_005, wire_closed_inside_0_025, wire_closed_inside_0_075, wire_unclosed_outside_0_005, wire_unclosed_outside_0_025, wire_unclosed_outside_0_075 mkoffset 2d offset of closed and unclosed planar wires with different offset step and directions of offset ( inside / outside )


This group allows testing construction of pipes (sweeping of a contour along profile).

DRAW module: MODELING (package BRepTest)

Grid Commands Functionality
Standard pipe


This group allows testing construction of prisms.

DRAW module: MODELING (package BRepTest)

Grid Commands Functionality
seminf prism


This group allows testing sewing of faces by connecting edges.

DRAW module: MODELING (package BRepTest)

Grid Commands Functionality
tol_0_01 sewing Sewing faces with tolerance 0.01
tol_1 sewing Sewing faces with tolerance 1
tol_100 sewing Sewing faces with tolerance 100


This group allows testing construction of shell or a solid passing through a set of sections in a given sequence (loft).

Grid Commands Functionality
solids thrusection Lofting with resulting solid
not_solids thrusection Lofting with resulting shell or face


This group allows testing extended data exchange packages.

Grid Commands Functionality
dxc, dxc_add_ACL, dxc_add_CL, igs_to_dxc, igs_add_ACL, brep_to_igs_add_CL, stp_to_dxc, stp_add_ACL, brep_to_stp_add_CL, brep_to_dxc, add_ACL_brep, brep_add_CL Subgroups are divided by format of source file, by format of result file and by type of document modification. For example, brep_to_igs means that the source shape in brep format was added to the document, which was saved into igs format after that. The postfix add_CL means that colors and layers were initialized in the document before saving and the postfix add_ACL corresponds to the creation of assembly and initialization of colors and layers in a document before saving.

Mapping of OCCT functionality to grid names in group *bugs*

OCCT Module / Mantis category Toolkits Test grid in group bugs
Application Framework PTKernel, TKPShape, TKCDF, TKLCAF, TKCAF, TKBinL, TKXmlL, TKShapeSchema, TKPLCAF, TKBin, TKXml, TKPCAF, FWOSPlugin, TKStdLSchema, TKStdSchema, TKTObj, TKBinTObj, TKXmlTObj caf
Draw TKDraw, TKTopTest, TKViewerTest, TKXSDRAW, TKDCAF, TKXDEDRAW, TKTObjDRAW, TKQADraw, DRAWEXE, Problems of testing system draw
Shape Healing TKShHealing heal
Mesh TKMesh, TKXMesh mesh
Data Exchange TKIGES iges
Data Exchange TKSTEPBase, TKSTEPAttr, TKSTEP209, TKSTEP step
Data Exchange TKSTL, TKVRML stlvrml
Foundation Classes TKernel, TKMath fclasses
Modeling_algorithms TKGeomAlgo, TKTopAlgo, TKPrim, TKBO, TKBool, TKHLR, TKFillet, TKOffset, TKFeat, TKXMesh modalg
Modeling Data TKG2d, TKG3d, TKGeomBase, TKBRep moddata
Visualization TKService, TKV2d, TKV3d, TKOpenGl, TKMeshVS, TKNIS vis

Recommended approaches to checking test results

Shape validity

Run command checkshape on the result (or intermediate) shape and make sure that parse.rules of the test grid or group reports bad shapes (usually recognized by word "Faulty") as error.


checkshape result

To check the number of faults in the shape command checkfaults can be used.

Use: checkfaults shape source_shape [ref_value=0]

The default syntax of checkfaults command:

checkfaults results a_1

The command will check the number of faults in the source shape (a_1) and compare it with number of faults in the resulting shape (result). If shape result contains more faults, you will get an error:

checkfaults results a_1
Error : Number of faults is 5

It is possible to set the reference value for comparison (reference value is 4):

checkfaults results a_1 4

If number of faults in the resulting shape is unstable, reference value should be set to "-1". As a result command checkfaults will return the following error:

checkfaults results a_1 -1
Error : Number of faults is UNSTABLE

Shape tolerance

The maximal tolerance of sub-shapes of each kind of the resulting shape can be extracted from output of tolerance command as follows:

set tolerance [tolerance result]
regexp { *FACE +: +MAX=([-0-9.+eE]+)} $tolerance dummy max_face
regexp { *EDGE +: +MAX=([-0-9.+eE]+)} $tolerance dummy max_edgee
regexp { *VERTEX +: +MAX=([-0-9.+eE]+)} $tolerance dummy max_vertex

It is possible to use command checkmaxtol to check maximal tolerance of shape and compare it with reference value.

Use: checkmaxtol shape [options...]

Allowed options are:

  • -ref – reference value of maximum tolerance;
  • -source – list of shapes to compare with;
  • -min_tol – minimum tolerance for comparison;
  • -multi_tol – tolerance multiplier.

The default syntax of checkmaxtol command for comparison with the reference value:

checkmaxtol result -ref 0.00001

There is an opportunity to compare max tolerance of resulting shape with max tolerance of source shape. In the following example command checkmaxtol gets max tolerance among objects a_1 and a_2. Then it chooses the maximum value between founded tolerance and value -min_tol (0.000001) and multiply it on the coefficient -multi_tol (i.e. 2):

checkmaxtol result -source {a_1 a_2} -min_tol 0.000001 -multi_tol 2

If the value of maximum tolerance more than founded tolerance for comparison, the command will return an error.

Also, command checkmaxtol can be used to get max tolerance of the shape:

set maxtol [checkmaxtol result]

Shape volume, area, or length

Use command vprops, sprops, or lprops to correspondingly measure volume, area, or length of the shape produced by the test. The value can be extracted from the result of the command by regexp.


# check area of shape result with 1% tolerance
regexp {Mass +: +([-0-9.+eE]+)} [sprops result] dummy area
if { abs($area - $expected) > 0.1 + 0.01 * abs ($area) } {
puts "Error: The area of result shape is $area, while expected $expected"

Memory leaks

The test system measures the amount of memory used by each test case. Considerable deviations (as well as the overall difference) in comparison with reference results can be reported by command testdiff (see Checking non-regression of performance, memory, and visualization).

To check memory leak on a particular operation, run it in a cycle, measure the memory consumption at each step and compare it with a threshold value. The command checktrend (defined in tests/bugs/begin) can be used to analyze a sequence of memory measurements and to get a statistically based evaluation of the leak presence.


set listmem {}
for {set i 1} {$i < 100} {incr i} {
# run suspect operation
# check memory usage (with tolerance equal to half page size)
lappend listmem [expr [meminfo w] / 1024]
if { [checktrend $listmem 0 256 "Memory leak detected"] } {
puts "No memory leak, $i iterations"


The following command sequence allows you to take a snapshot of the viewer, give it the name of the test case, and save in the directory indicated by Tcl variable imagedir.

vdisplay result
vsetdispmode 1
vdump $imagedir/${casename}_shading.png

This image will be included in the HTML log produced by testgrid command and will be checked for non-regression through comparison of images by command testdiff.

Also it is possible to use command checkview to make a snapshot of the viewer.

Use: checkview [options...] Allowed options are:

  • -display shapename – displays shape with name shapename;
  • -3d – displays shape in 3d viewer;
  • -2d [ v2d / smallview ] - displays shape in 2d viewer (the default viewer is smallview);
  • -path PATH – sets the location of the saved viewer screenshot;
  • -vdispmode N – sets vdispmode for 3d viewer (default value is 1)
  • -screenshot – makes a screenshot of already created viewer
  • The procedure can check a property of shape (length, area or volume) and compare it with value N:
    • -l [N]
    • -s [N]
    • -v [N]
    • If the current property is equal to value N, the shape is marked as valid in the procedure.
    • If value N is not given, the procedure will mark the shape as valid if the current property is non-zero.
  • -with {a b c} – displays shapes a, b and c together with the shape (if the shape is valid)
  • -otherwise {d e f} – displays shapes d, e and f instead of the shape (if the shape is NOT valid)

Note that is required to use either option -2d or option -3d.


checkview -display result -2d -path ${imagedir}/${test_image}.png
checkview -display result -3d -path ${imagedir}/${test_image}.png
checkview -display result_2d -2d v2d -path ${imagedir}/${test_image}.png
box a 10 10 10
box b 5 5 5 10 10 10
bcut result b a
set result_vertices [explode result v]
checkview -display result -2d -with ${result_vertices} -otherwise { a b } -l -path ${imagedir}/${test_image}.png
box a 10 10 10
box b 5 5 5 10 10 10
bcut result b a
vdisplay a b
checkview -screenshot -3d -path ${imagedir}/${test_image}.png

Number of free edges

Procedure checkfreebounds compares the number of free edges with a reference value.

Use: checkfreebounds shape ref_value [options...]

Allowed options are:

  • -tol N – used tolerance (default -0.01);
  • -type N – used type, possible values are "closed" and "opened" (default "closed").
checkfreebounds result 13

Option -tol N defines tolerance for command freebounds, which is used within command checkfreebounds.

Option -type N is used to select the type of counted free edges: closed or open.

If the number of free edges in the resulting shape is unstable, the reference value should be set to "-1". As a result command checkfreebounds will return the following error:

checkfreebounds result -1
Error : Number of free edges is UNSTABLE

Compare numbers

Procedure checkreal checks the equality of two reals with a tolerance (relative and absolute).

Use: checkreal name value expected tol_abs tol_rel

checkreal "Some important value" $value 5 0.0001 0.01

Check number of sub-shapes

Procedure checknbshapes compares the number of sub-shapes in "shape" with the given reference data.

Use: checknbshapes shape [options...]

Allowed options are:

  • -vertex N
  • -edge N
  • -wire N
  • -face N
  • -shell N
  • -solid N
  • -compsolid N
  • -compound N
  • -shape N
  • -t – compares the number of sub-shapes in "shape" counting the same sub-shapes with different location as different sub-shapes.
  • -m msg – prints "msg" in case of error
checknbshapes result -vertex 8 -edge 4

Check pixel color

Command checkcolor can be used to check pixel color.

Use: checkcolor x y red green blue


  • x, y – pixel coordinates;
  • red green blue – expected pixel color (values from 0 to 1).

This procedure checks color with tolerance (5x5 area).

Next example will compare color of point with coordinates x=100 y=100 with RGB color R=1 G=0 B=0. If colors are not equal, procedure will check the nearest ones points (5x5 area)

checkcolor 100 100 1 0 0

Compute length, area and volume of input shape

Procedure checkprops computes length, area and volume of the input shape.

Use: checkprops shapename [options...]

Allowed options are:

  • -l LENGTH – command lprops, computes the mass properties of all edges in the shape with a linear density of 1;
  • -s AREA – command sprops, computes the mass properties of all faces with a surface density of 1;
  • -v VOLUME – command vprops, computes the mass properties of all solids with a density of 1;
  • -eps EPSILON – the epsilon defines relative precision of computation;
  • -deps DEPSILON – the epsilon defines relative precision to compare corresponding values;
  • -equal SHAPE – compares area, volume and length of input shapes. Puts error if they are not equal;
  • -notequal SHAPE – compares area, volume and length of input shapes. Puts error if they are equal.

Options -l, -s and -v are independent and can be used in any order. Tolerance epsilon is the same for all options.

checkprops result -s 6265.68
checkprops result -s -equal FaceBrep

Parse output dump and compare it with reference values

Procedure checkdump is used to parse output dump and compare it with reference values.

Use: checkdump shapename [options...]

Allowed options are:

  • -name NAME – list of parsing parameters (e.g. Center, Axis, etc.);
  • -ref VALUE – list of reference values for each parameter in NAME;
  • -eps EPSILON – the epsilon defines relative precision of computation.
checkdump result -name {Center Axis XAxis YAxis Radii} -ref {{-70 0} {-1 -0} {-1 -0} {0 -1} {20 10}} -eps 0.01

Compute length of input curve

Procedure checklength computes length of the input curve.

Use: checklength curvename [options...]

Allowed options are:

  • -l LENGTH – command length, computes the length of the input curve with precision of computation;
  • -eps EPSILON – the epsilon defines a relative precision of computation;
  • -equal CURVE – compares the length of input curves. Puts error if they are not equal;
  • -notequal CURVE – compares the length of input curves. Puts error if they are equal.
checklength cp1 -l 7.278
checklength res -l -equal ext_1

Check maximum deflection, number of triangles and nodes in mesh

Command checktrinfo can be used to to check the maximum deflection, as well as the number of nodes and triangles in mesh.

Use: checktrinfo shapename [options...]

Allowed options are:

  • -tri [N] – compares the current number of triangles in shapename mesh with the given reference data. If reference value N is not given and the current number of triangles is equal to 0, procedure checktrinfo will print an error.
  • -nod [N] – compares the current number of nodes in shapename mesh with the given reference data. If reference value N is not given and the current number of nodes is equal to 0, procedure checktrinfo will print an error.
  • -defl [N] – compares the current value of maximum deflection in shapename mesh with the given reference data. If reference value N is not given and current maximum deflection is equal to 0, procedure checktrinfo will print an error.
  • -max_defl N – compares the current value of maximum deflection in shapename mesh with the max possible value.
  • -tol_abs_tri N – absolute tolerance for comparison of number of triangles (default value 0).
  • -tol_rel_tri N – relative tolerance for comparison of number of triangles (default value 0).
  • -tol_abs_nod N – absolute tolerance for comparison of number of nodes (default value 0).
  • -tol_rel_nod N – relative tolerance for comparison of number of nodes (default value 0).
  • -tol_abs_defl N – absolute tolerance for deflection comparison (default value 0).
  • -tol_rel_defl N – relative tolerance for deflection comparison (default value 0).
  • -ref [trinfo a] – compares deflection, number of triangles and nodes in shapename and a.

Note that options -tri, -nod and -defl do not work together with option -ref.


Comparison with some reference values:

checktrinfo result -tri 129 -nod 131 -defl 0.01

Comparison with another mesh:

checktrinfo result -ref [tringo a]

Comparison of deflection with the max possible value:

checktrinfo result -max_defl 1

Check that the current values are not equal to zero:

checktrinfo result -tri -nod -defl

Check that the number of triangles and the number of nodes are not equal to some specific values:

checktrinfo result -tri !10 -nod !8

It is possible to compare current values with reference values with some tolerances. Use options -tol_* for that.

checktrinfo result -defl 1 -tol_abs_defl 0.001