Provided by: tcl8.5-doc_8.5.19-4_all 
NAME
tcltest - Test harness support code and utilities
SYNOPSIS
package require tcltest ?2.3?
tcltest::test name description ?option value ...?
tcltest::test name description ?constraints? body result
tcltest::loadTestedCommands
tcltest::makeDirectory name ?directory?
tcltest::removeDirectory name ?directory?
tcltest::makeFile contents name ?directory?
tcltest::removeFile name ?directory?
tcltest::viewFile name ?directory?
tcltest::cleanupTests ?runningMultipleTests?
tcltest::runAllTests
tcltest::configure
tcltest::configure option
tcltest::configure option value ?option value ...?
tcltest::customMatch mode command
tcltest::testConstraint constraint ?value?
tcltest::outputChannel ?channelID?
tcltest::errorChannel ?channelID?
tcltest::interpreter ?interp?
tcltest::debug ?level?
tcltest::errorFile ?filename?
tcltest::limitConstraints ?boolean?
tcltest::loadFile ?filename?
tcltest::loadScript ?script?
tcltest::match ?patternList?
tcltest::matchDirectories ?patternList?
tcltest::matchFiles ?patternList?
tcltest::outputFile ?filename?
tcltest::preserveCore ?level?
tcltest::singleProcess ?boolean?
tcltest::skip ?patternList?
tcltest::skipDirectories ?patternList?
tcltest::skipFiles ?patternList?
tcltest::temporaryDirectory ?directory?
tcltest::testsDirectory ?directory?
tcltest::verbose ?level?
tcltest::test name description optionList
tcltest::bytestring string
tcltest::normalizeMsg msg
tcltest::normalizePath pathVar
tcltest::workingDirectory ?dir?
_________________________________________________________________________________________________
DESCRIPTION
The tcltest package provides several utility commands useful in the construction of test
suites for code instrumented to be run by evaluation of Tcl commands. Notably the built-
in commands of the Tcl library itself are tested by a test suite using the tcltest
package.
All the commands provided by the tcltest package are defined in and exported from the
::tcltest namespace, as indicated in the SYNOPSIS above. In the following sections, all
commands will be described by their simple names, in the interest of brevity.
The central command of tcltest is test that defines and runs a test. Testing with test
involves evaluation of a Tcl script and comparing the result to an expected result, as
configured and controlled by a number of options. Several other commands provided by
tcltest govern the configuration of test and the collection of many test commands into
test suites.
See CREATING TEST SUITES WITH TCLTEST below for an extended example of how to use the
commands of tcltest to produce test suites for your Tcl-enabled code.
COMMANDS
test name description ?option value ...?
Defines and possibly runs a test with the name name and description description.
The name and description of a test are used in messages reported by test during the
test, as configured by the options of tcltest. The remaining option value
arguments to test define the test, including the scripts to run, the conditions
under which to run them, the expected result, and the means by which the expected
and actual results should be compared. See TESTS below for a complete description
of the valid options and how they define a test. The test command returns an empty
string.
test name description ?constraints? body result
This form of test is provided to support test suites written for version 1 of the
tcltest package, and also a simpler interface for a common usage. It is the same
as “test name description -constraints constraints -body body -result result”. All
other options to test take their default values. When constraints is omitted, this
form of test can be distinguished from the first because all options begin with
“-”.
loadTestedCommands
Evaluates in the caller's context the script specified by configure -load or
configure -loadfile. Returns the result of that script evaluation, including any
error raised by the script. Use this command and the related configuration options
to provide the commands to be tested to the interpreter running the test suite.
makeFile contents name ?directory?
Creates a file named name relative to directory directory and write contents to
that file using the encoding encoding system. If contents does not end with a
newline, a newline will be appended so that the file named name does end with a
newline. Because the system encoding is used, this command is only suitable for
making text files. The file will be removed by the next evaluation of
cleanupTests, unless it is removed by removeFile first. The default value of
directory is the directory configure -tmpdir. Returns the full path of the file
created. Use this command to create any text file required by a test with contents
as needed.
removeFile name ?directory?
Forces the file referenced by name to be removed. This file name should be
relative to directory. The default value of directory is the directory configure
-tmpdir. Returns an empty string. Use this command to delete files created by
makeFile.
makeDirectory name ?directory?
Creates a directory named name relative to directory directory. The directory will
be removed by the next evaluation of cleanupTests, unless it is removed by
removeDirectory first. The default value of directory is the directory configure
-tmpdir. Returns the full path of the directory created. Use this command to
create any directories that are required to exist by a test.
removeDirectory name ?directory?
Forces the directory referenced by name to be removed. This directory should be
relative to directory. The default value of directory is the directory configure
-tmpdir. Returns an empty string. Use this command to delete any directories
created by makeDirectory.
viewFile file ?directory?
Returns the contents of file, except for any final newline, just as read -nonewline
would return. This file name should be relative to directory. The default value
of directory is the directory configure -tmpdir. Use this command as a convenient
way to turn the contents of a file generated by a test into the result of that test
for matching against an expected result. The contents of the file are read using
the system encoding, so its usefulness is limited to text files.
cleanupTests
Intended to clean up and summarize after several tests have been run. Typically
called once per test file, at the end of the file after all tests have been
completed. For best effectiveness, be sure that the cleanupTests is evaluated even
if an error occurs earlier in the test file evaluation.
Prints statistics about the tests run and removes files that were created by
makeDirectory and makeFile since the last cleanupTests. Names of files and
directories in the directory configure -tmpdir created since the last cleanupTests,
but not created by makeFile or makeDirectory are printed to outputChannel. This
command also restores the original shell environment, as described by the ::env
array. Returns an empty string.
runAllTests
This is a master command meant to run an entire suite of tests, spanning multiple
files and/or directories, as governed by the configurable options of tcltest. See
RUNNING ALL TESTS below for a complete description of the many variations possible
with runAllTests.
CONFIGURATION COMMANDS
configure
Returns the list of configurable options supported by tcltest. See CONFIGURABLE
OPTIONS below for the full list of options, their valid values, and their effect on
tcltest operations.
configure option
Returns the current value of the supported configurable option option. Raises an
error if option is not a supported configurable option.
configure option value ?option value ...?
Sets the value of each configurable option option to the corresponding value value,
in order. Raises an error if an option is not a supported configurable option, or
if value is not a valid value for the corresponding option, or if a value is not
provided. When an error is raised, the operation of configure is halted, and
subsequent option value arguments are not processed.
If the environment variable ::env(TCLTEST_OPTIONS) exists when the tcltest package
is loaded (by package require tcltest) then its value is taken as a list of
arguments to pass to configure. This allows the default values of the
configuration options to be set by the environment.
customMatch mode script
Registers mode as a new legal value of the -match option to test. When the -match
mode option is passed to test, the script script will be evaluated to compare the
actual result of evaluating the body of the test to the expected result. To
perform the match, the script is completed with two additional words, the expected
result, and the actual result, and the completed script is evaluated in the global
namespace. The completed script is expected to return a boolean value indicating
whether or not the results match. The built-in matching modes of test are exact,
glob, and regexp.
testConstraint constraint ?boolean?
Sets or returns the boolean value associated with the named constraint. See TEST
CONSTRAINTS below for more information.
interpreter ?executableName?
Sets or returns the name of the executable to be execed by runAllTests to run each
test file when configure -singleproc is false. The default value for interpreter
is the name of the currently running program as returned by info nameofexecutable.
outputChannel ?channelID?
Sets or returns the output channel ID. This defaults to stdout. Any test that
prints test related output should send that output to outputChannel rather than
letting that output default to stdout.
errorChannel ?channelID?
Sets or returns the error channel ID. This defaults to stderr. Any test that
prints error messages should send that output to errorChannel rather than printing
directly to stderr.
SHORTCUT COMMANDS
debug ?level?
Same as configure -debug ?level?.
errorFile ?filename?
Same as configure -errfile ?filename?.
limitConstraints ?boolean?
Same as configure -limitconstraints ?boolean?.
loadFile ?filename?
Same as configure -loadfile ?filename?.
loadScript ?script?
Same as configure -load ?script?.
match ?patternList?
Same as configure -match ?patternList?.
matchDirectories ?patternList?
Same as configure -relateddir ?patternList?.
matchFiles ?patternList?
Same as configure -file ?patternList?.
outputFile ?filename?
Same as configure -outfile ?filename?.
preserveCore ?level?
Same as configure -preservecore ?level?.
singleProcess ?boolean?
Same as configure -singleproc ?boolean?.
skip ?patternList?
Same as configure -skip ?patternList?.
skipDirectories ?patternList?
Same as configure -asidefromdir ?patternList?.
skipFiles ?patternList?
Same as configure -notfile ?patternList?.
temporaryDirectory ?directory?
Same as configure -tmpdir ?directory?.
testsDirectory ?directory?
Same as configure -testdir ?directory?.
verbose ?level?
Same as configure -verbose ?level?.
OTHER COMMANDS
The remaining commands provided by tcltest have better alternatives provided by tcltest or
Tcl itself. They are retained to support existing test suites, but should be avoided in
new code.
test name description optionList
This form of test was provided to enable passing many options spanning several
lines to test as a single argument quoted by braces, rather than needing to
backslash quote the newlines between arguments to test. The optionList argument is
expected to be a list with an even number of elements representing option and value
arguments to pass to test. However, these values are not passed directly, as in
the alternate forms of switch. Instead, this form makes an unfortunate attempt to
overthrow Tcl's substitution rules by performing substitutions on some of the list
elements as an attempt to implement a “do what I mean” interpretation of a brace-
enclosed “block”. The result is nearly impossible to document clearly, and for
that reason this form is not recommended. See the examples in CREATING TEST SUITES
WITH TCLTEST below to see that this form is really not necessary to avoid
backslash-quoted newlines. If you insist on using this form, examine the source
code of tcltest if you want to know the substitution details, or just enclose the
third through last argument to test in braces and hope for the best.
workingDirectory ?directoryName?
Sets or returns the current working directory when the test suite is running. The
default value for workingDirectory is the directory in which the test suite was
launched. The Tcl commands cd and pwd are sufficient replacements.
normalizeMsg msg
Returns the result of removing the “extra” newlines from msg, where “extra” is
rather imprecise. Tcl offers plenty of string processing commands to modify
strings as you wish, and customMatch allows flexible matching of actual and
expected results.
normalizePath pathVar
Resolves symlinks in a path, thus creating a path without internal redirection. It
is assumed that pathVar is absolute. pathVar is modified in place. The Tcl
command file normalize is a sufficient replacement.
bytestring string
Construct a string that consists of the requested sequence of bytes, as opposed to
a string of properly formed UTF-8 characters using the value supplied in string.
This allows the tester to create denormalized or improperly formed strings to pass
to C procedures that are supposed to accept strings with embedded NULL types and
confirm that a string result has a certain pattern of bytes. This is exactly
equivalent to the Tcl command encoding convertfrom identity.
TESTS
The test command is the heart of the tcltest package. Its essential function is to
evaluate a Tcl script and compare the result with an expected result. The options of test
define the test script, the environment in which to evaluate it, the expected result, and
how the compare the actual result to the expected result. Some configuration options of
tcltest also influence how test operates.
The valid options for test are summarized:
test name description
?-constraints keywordList|expression?
?-setup setupScript?
?-body testScript?
?-cleanup cleanupScript?
?-result expectedAnswer?
?-output expectedOutput?
?-errorOutput expectedError?
?-returnCodes codeList?
?-match mode?
The name may be any string. It is conventional to choose a name according to the pattern:
target-majorNum.minorNum
For white-box (regression) tests, the target should be the name of the C function or Tcl
procedure being tested. For black-box tests, the target should be the name of the feature
being tested. Some conventions call for the names of black-box tests to have the suffix
_bb. Related tests should share a major number. As a test suite evolves, it is best to
have the same test name continue to correspond to the same test, so that it remains
meaningful to say things like “Test foo-1.3 passed in all releases up to 3.4, but began
failing in release 3.5.”
During evaluation of test, the name will be compared to the lists of string matching
patterns returned by configure -match, and configure -skip. The test will be run only if
name matches any of the patterns from configure -match and matches none of the patterns
from configure -skip.
The description should be a short textual description of the test. The description is
included in output produced by the test, typically test failure messages. Good
description values should briefly explain the purpose of the test to users of a test
suite. The name of a Tcl or C function being tested should be included in the description
for regression tests. If the test case exists to reproduce a bug, include the bug ID in
the description.
Valid attributes and associated values are:
-constraints keywordList|expression
The optional -constraints attribute can be list of one or more keywords or an
expression. If the -constraints value is a list of keywords, each of these
keywords should be the name of a constraint defined by a call to testConstraint.
If any of the listed constraints is false or does not exist, the test is skipped.
If the -constraints value is an expression, that expression is evaluated. If the
expression evaluates to true, then the test is run. Note that the expression form
of -constraints may interfere with the operation of configure -constraints and
configure -limitconstraints, and is not recommended. Appropriate constraints
should be added to any tests that should not always be run. That is, conditional
evaluation of a test should be accomplished by the -constraints option, not by
conditional evaluation of test. In that way, the same number of tests are always
reported by the test suite, though the number skipped may change based on the
testing environment. The default value is an empty list. See TEST CONSTRAINTS
below for a list of built-in constraints and information on how to add your own
constraints.
-setup script
The optional -setup attribute indicates a script that will be run before the script
indicated by the -body attribute. If evaluation of script raises an error, the
test will fail. The default value is an empty script.
-body script
The -body attribute indicates the script to run to carry out the test. It must
return a result that can be checked for correctness. If evaluation of script
raises an error, the test will fail. The default value is an empty script.
-cleanup script
The optional -cleanup attribute indicates a script that will be run after the
script indicated by the -body attribute. If evaluation of script raises an error,
the test will fail. The default value is an empty script.
-match mode
The -match attribute determines how expected answers supplied by -result, -output,
and -errorOutput are compared. Valid values for mode are regexp, glob, exact, and
any value registered by a prior call to customMatch. The default value is exact.
-result expectedValue
The -result attribute supplies the expectedValue against which the return value
from script will be compared. The default value is an empty string.
-output expectedValue
The -output attribute supplies the expectedValue against which any output sent to
stdout or outputChannel during evaluation of the script(s) will be compared. Note
that only output printed using ::puts is used for comparison. If -output is not
specified, output sent to stdout and outputChannel is not processed for comparison.
-errorOutput expectedValue
The -errorOutput attribute supplies the expectedValue against which any output sent
to stderr or errorChannel during evaluation of the script(s) will be compared. Note
that only output printed using ::puts is used for comparison. If -errorOutput is
not specified, output sent to stderr and errorChannel is not processed for
comparison.
-returnCodes expectedCodeList
The optional -returnCodes attribute supplies expectedCodeList, a list of return
codes that may be accepted from evaluation of the -body script. If evaluation of
the -body script returns a code not in the expectedCodeList, the test fails. All
return codes known to return, in both numeric and symbolic form, including extended
return codes, are acceptable elements in the expectedCodeList. Default value is
“ok”return.
To pass, a test must successfully evaluate its -setup, -body, and -cleanup scripts. The
return code of the -body script and its result must match expected values, and if
specified, output and error data from the test must match expected -output and
-errorOutput values. If any of these conditions are not met, then the test fails. Note
that all scripts are evaluated in the context of the caller of test.
As long as test is called with valid syntax and legal values for all attributes, it will
not raise an error. Test failures are instead reported as output written to
outputChannel. In default operation, a successful test produces no output. The output
messages produced by test are controlled by the configure -verbose option as described in
CONFIGURABLE OPTIONS below. Any output produced by the test scripts themselves should be
produced using ::puts to outputChannel or errorChannel, so that users of the test suite
may easily capture output with the configure -outfile and configure -errfile options, and
so that the -output and -errorOutput attributes work properly.
TEST CONSTRAINTS
Constraints are used to determine whether or not a test should be skipped. Each
constraint has a name, which may be any string, and a boolean value. Each test has a
-constraints value which is a list of constraint names. There are two modes of constraint
control. Most frequently, the default mode is used, indicated by a setting of configure
-limitconstraints to false. The test will run only if all constraints in the list are
true-valued. Thus, the -constraints option of test is a convenient, symbolic way to
define any conditions required for the test to be possible or meaningful. For example, a
test with -constraints unix will only be run if the constraint unix is true, which
indicates the test suite is being run on a Unix platform.
Each test should include whatever -constraints are required to constrain it to run only
where appropriate. Several constraints are pre-defined in the tcltest package, listed
below. The registration of user-defined constraints is performed by the testConstraint
command. User-defined constraints may appear within a test file, or within the script
specified by the configure -load or configure -loadfile options.
The following is a list of constraints pre-defined by the tcltest package itself:
singleTestInterp
test can only be run if all test files are sourced into a single interpreter
unix test can only be run on any Unix platform
win test can only be run on any Windows platform
nt test can only be run on any Windows NT platform
95 test can only be run on any Windows 95 platform
98 test can only be run on any Windows 98 platform
mac test can only be run on any Mac platform
unixOrWin
test can only be run on a Unix or Windows platform
macOrWin
test can only be run on a Mac or Windows platform
macOrUnix
test can only be run on a Mac or Unix platform
tempNotWin
test can not be run on Windows. This flag is used to temporarily disable a test.
tempNotMac
test can not be run on a Mac. This flag is used to temporarily disable a test.
unixCrash
test crashes if it is run on Unix. This flag is used to temporarily disable a
test.
winCrash
test crashes if it is run on Windows. This flag is used to temporarily disable a
test.
macCrash
test crashes if it is run on a Mac. This flag is used to temporarily disable a
test.
emptyTest
test is empty, and so not worth running, but it remains as a place-holder for a
test to be written in the future. This constraint has value false to cause tests
to be skipped unless the user specifies otherwise.
knownBug
test is known to fail and the bug is not yet fixed. This constraint has value
false to cause tests to be skipped unless the user specifies otherwise.
nonPortable
test can only be run in some known development environment. Some tests are
inherently non-portable because they depend on things like word length, file system
configuration, window manager, etc. This constraint has value false to cause tests
to be skipped unless the user specifies otherwise.
userInteraction
test requires interaction from the user. This constraint has value false to causes
tests to be skipped unless the user specifies otherwise.
interactive
test can only be run in if the interpreter is in interactive mode (when the global
tcl_interactive variable is set to 1).
nonBlockFiles
test can only be run if platform supports setting files into nonblocking mode
asyncPipeClose
test can only be run if platform supports async flush and async close on a pipe
unixExecs
test can only be run if this machine has Unix-style commands cat, echo, sh, wc, rm,
sleep, fgrep, ps, chmod, and mkdir available
hasIsoLocale
test can only be run if can switch to an ISO locale
root test can only run if Unix user is root
notRoot
test can only run if Unix user is not root
eformat
test can only run if app has a working version of sprintf with respect to the “e”
format of floating-point numbers.
stdio test can only be run if interpreter can be opened as a pipe.
The alternative mode of constraint control is enabled by setting configure
-limitconstraints to true. With that configuration setting, all existing constraints
other than those in the constraint list returned by configure -constraints are set to
false. When the value of configure -constraints is set, all those constraints are set to
true. The effect is that when both options configure -constraints and configure
-limitconstraints are in use, only those tests including only constraints from the
configure -constraints list are run; all others are skipped. For example, one might set
up a configuration with
configure -constraints knownBug \
-limitconstraints true \
-verbose pass
to run exactly those tests that exercise known bugs, and discover whether any of them
pass, indicating the bug had been fixed.
RUNNING ALL TESTS
The single command runAllTests is evaluated to run an entire test suite, spanning many
files and directories. The configuration options of tcltest control the precise
operations. The runAllTests command begins by printing a summary of its configuration to
outputChannel.
Test files to be evaluated are sought in the directory configure -testdir. The list of
files in that directory that match any of the patterns in configure -file and match none
of the patterns in configure -notfile is generated and sorted. Then each file will be
evaluated in turn. If configure -singleproc is true, then each file will be sourced in
the caller's context. If it is false, then a copy of interpreter will be exec'd to
evaluate each file. The multi-process operation is useful when testing can cause errors
so severe that a process terminates. Although such an error may terminate a child process
evaluating one file, the master process can continue with the rest of the test suite. In
multi-process operation, the configuration of tcltest in the master process is passed to
the child processes as command line arguments, with the exception of configure -outfile.
The runAllTests command in the master process collects all output from the child processes
and collates their results into one master report. Any reports of individual test
failures, or messages requested by a configure -verbose setting are passed directly on to
outputChannel by the master process.
After evaluating all selected test files, a summary of the results is printed to
outputChannel. The summary includes the total number of tests evaluated, broken down into
those skipped, those passed, and those failed. The summary also notes the number of files
evaluated, and the names of any files with failing tests or errors. A list of the
constraints that caused tests to be skipped, and the number of tests skipped for each is
also printed. Also, messages are printed if it appears that evaluation of a test file has
caused any temporary files to be left behind in configure -tmpdir.
Having completed and summarized all selected test files, runAllTests then recursively acts
on subdirectories of configure -testdir. All subdirectories that match any of the
patterns in configure -relateddir and do not match any of the patterns in configure
-asidefromdir are examined. If a file named all.tcl is found in such a directory, it will
be sourced in the caller's context. Whether or not an examined directory contains an
all.tcl file, its subdirectories are also scanned against the configure -relateddir and
configure -asidefromdir patterns. In this way, many directories in a directory tree can
have all their test files evaluated by a single runAllTests command.
CONFIGURABLE OPTIONS
The configure command is used to set and query the configurable options of tcltest. The
valid options are:
-singleproc boolean
Controls whether or not runAllTests spawns a child process for each test file. No
spawning when boolean is true. Default value is false.
-debug level
Sets the debug level to level, an integer value indicating how much debugging
information should be printed to stdout. Note that debug messages always go to
stdout, independent of the value of configure -outfile. Default value is 0.
Levels are defined as:
0 Do not display any debug information.
1 Display information regarding whether a test is skipped because it does not
match any of the tests that were specified using by configure -match
(userSpecifiedNonMatch) or matches any of the tests specified by configure
-skip (userSpecifiedSkip). Also print warnings about possible lack of
cleanup or balance in test files. Also print warnings about any re-use of
test names.
2 Display the flag array parsed by the command line processor, the contents of
the ::env array, and all user-defined variables that exist in the current
namespace as they are used.
3 Display information regarding what individual procs in the test harness are
doing.
-verbose level
Sets the type of output verbosity desired to level, a list of zero or more of the
elements body, pass, skip, start, error and line. Default value is {body error}.
Levels are defined as:
body (b)
Display the body of failed tests
pass (p)
Print output when a test passes
skip (s)
Print output when a test is skipped
start (t)
Print output whenever a test starts
error (e)
Print errorInfo and errorCode, if they exist, when a test return code does
not match its expected return code
line (l)
Print source file line information of failed tests
The single letter abbreviations noted above are also recognized so that “configure
-verbose pt” is the same as “configure -verbose {pass start}”.
-preservecore level
Sets the core preservation level to level. This level determines how stringent
checks for core files are. Default value is 0. Levels are defined as:
0 No checking — do not check for core files at the end of each test command,
but do check for them in runAllTests after all test files have been
evaluated.
1 Also check for core files at the end of each test command.
2 Check for core files at all times described above, and save a copy of each
core file produced in configure -tmpdir.
-limitconstraints boolean
Sets the mode by which test honors constraints as described in TESTS above.
Default value is false.
-constraints list
Sets all the constraints in list to true. Also used in combination with configure
-limitconstraints true to control an alternative constraint mode as described in
TESTS above. Default value is an empty list.
-tmpdir directory
Sets the temporary directory to be used by makeFile, makeDirectory, viewFile,
removeFile, and removeDirectory as the default directory where temporary files and
directories created by test files should be created. Default value is
workingDirectory.
-testdir directory
Sets the directory searched by runAllTests for test files and subdirectories.
Default value is workingDirectory.
-file patternList
Sets the list of patterns used by runAllTests to determine what test files to
evaluate. Default value is “*.test”.
-notfile patternList
Sets the list of patterns used by runAllTests to determine what test files to skip.
Default value is “l.*.test”, so that any SCCS lock files are skipped.
-relateddir patternList
Sets the list of patterns used by runAllTests to determine what subdirectories to
search for an all.tcl file. Default value is “*”.
-asidefromdir patternList
Sets the list of patterns used by runAllTests to determine what subdirectories to
skip when searching for an all.tcl file. Default value is an empty list.
-match patternList
Set the list of patterns used by test to determine whether a test should be run.
Default value is “*”.
-skip patternList
Set the list of patterns used by test to determine whether a test should be
skipped. Default value is an empty list.
-load script
Sets a script to be evaluated by loadTestedCommands. Default value is an empty
script.
-loadfile filename
Sets the filename from which to read a script to be evaluated by
loadTestedCommands. This is an alternative to -load. They cannot be used
together.
-outfile filename
Sets the file to which all output produced by tcltest should be written. A file
named filename will be opened for writing, and the resulting channel will be set as
the value of outputChannel.
-errfile filename
Sets the file to which all error output produced by tcltest should be written. A
file named filename will be opened for writing, and the resulting channel will be
set as the value of errorChannel.
CREATING TEST SUITES WITH TCLTEST
The fundamental element of a test suite is the individual test command. We begin with
several examples.
[1] Test of a script that returns normally.
test example-1.0 {normal return} {
format %s value
} value
[2] Test of a script that requires context setup and cleanup. Note the bracing and
indenting style that avoids any need for line continuation.
test example-1.1 {test file existence} -setup {
set file [makeFile {} test]
} -body {
file exists $file
} -cleanup {
removeFile test
} -result 1
[3] Test of a script that raises an error.
test example-1.2 {error return} -body {
error message
} -returnCodes error -result message
[4] Test with a constraint.
test example-1.3 {user owns created files} -constraints {
unix
} -setup {
set file [makeFile {} test]
} -body {
file attributes $file -owner
} -cleanup {
removeFile test
} -result $::tcl_platform(user)
At the next higher layer of organization, several test commands are gathered together into
a single test file. Test files should have names with the .test extension, because that
is the default pattern used by runAllTests to find test files. It is a good rule of thumb
to have one test file for each source code file of your project. It is good practice to
edit the test file and the source code file together, keeping tests synchronized with code
changes.
Most of the code in the test file should be the test commands. Use constraints to skip
tests, rather than conditional evaluation of test.
[5] Recommended system for writing conditional tests, using constraints to guard:
testConstraint X [expr $myRequirement]
test goodConditionalTest {} X {
# body
} result
[6] Discouraged system for writing conditional tests, using if to guard:
if $myRequirement {
test badConditionalTest {} {
#body
} result
}
Use the -setup and -cleanup options to establish and release all context requirements of
the test body. Do not make tests depend on prior tests in the file. Those prior tests
might be skipped. If several consecutive tests require the same context, the appropriate
setup and cleanup scripts may be stored in variable for passing to each tests -setup and
-cleanup options. This is a better solution than performing setup outside of test
commands, because the setup will only be done if necessary, and any errors during setup
will be reported, and not cause the test file to abort.
A test file should be able to be combined with other test files and not interfere with
them, even when configure -singleproc 1 causes all files to be evaluated in a common
interpreter. A simple way to achieve this is to have your tests define all their commands
and variables in a namespace that is deleted when the test file evaluation is complete. A
good namespace to use is a child namespace test of the namespace of the module you are
testing.
A test file should also be able to be evaluated directly as a script, not depending on
being called by a master runAllTests. This means that each test file should process
command line arguments to give the tester all the configuration control that tcltest
provides.
After all tests in a test file, the command cleanupTests should be called.
[7] Here is a sketch of a sample test file illustrating those points:
package require tcltest 2.2
eval ::tcltest::configure $argv
package require example
namespace eval ::example::test {
namespace import ::tcltest::*
testConstraint X [expr {...}]
variable SETUP {#common setup code}
variable CLEANUP {#common cleanup code}
test example-1 {} -setup $SETUP -body {
# First test
} -cleanup $CLEANUP -result {...}
test example-2 {} -constraints X -setup $SETUP -body {
# Second test; constrained
} -cleanup $CLEANUP -result {...}
test example-3 {} {
# Third test; no context required
} {...}
cleanupTests
}
namespace delete ::example::test
The next level of organization is a full test suite, made up of several test files. One
script is used to control the entire suite. The basic function of this script is to call
runAllTests after doing any necessary setup. This script is usually named all.tcl because
that is the default name used by runAllTests when combining multiple test suites into one
testing run.
[8] Here is a sketch of a sample test suite master script:
package require Tcl 8.4
package require tcltest 2.2
package require example
::tcltest::configure -testdir \
[file dirname [file normalize [info script]]]
eval ::tcltest::configure $argv
::tcltest::runAllTests
COMPATIBILITY
A number of commands and variables in the ::tcltest namespace provided by earlier releases
of tcltest have not been documented here. They are no longer part of the supported public
interface of tcltest and should not be used in new test suites. However, to continue to
support existing test suites written to the older interface specifications, many of those
deprecated commands and variables still work as before. For example, in many
circumstances, configure will be automatically called shortly after package require
tcltest 2.1 succeeds with arguments from the variable ::argv. This is to support test
suites that depend on the old behavior that tcltest was automatically configured from
command line arguments. New test files should not depend on this, but should explicitly
include
eval ::tcltest::configure $::argv
to establish a configuration from command line arguments.
KNOWN ISSUES
There are two known issues related to nested evaluations of test. The first issue relates
to the stack level in which test scripts are executed. Tests nested within other tests
may be executed at the same stack level as the outermost test. For example, in the
following code:
test level-1.1 {level 1} {
-body {
test level-2.1 {level 2} {
}
}
}
any script executed in level-2.1 may be executed at the same stack level as the script
defined for level-1.1.
In addition, while two tests have been run, results will only be reported by cleanupTests
for tests at the same level as test level-1.1. However, test results for all tests run
prior to level-1.1 will be available when test level-2.1 runs. What this means is that if
you try to access the test results for test level-2.1, it will may say that “m” tests have
run, “n” tests have been skipped, “o” tests have passed and “p” tests have failed, where
“m”, “n”, “o”, and “p” refer to tests that were run at the same test level as test
level-1.1.
Implementation of output and error comparison in the test command depends on usage of
::puts in your application code. Output is intercepted by redefining the ::puts command
while the defined test script is being run. Errors thrown by C procedures or printed
directly from C applications will not be caught by the test command. Therefore, usage of
the -output and -errorOutput options to test is useful only for pure Tcl applications that
use ::puts to produce output.
KEYWORDS
test, test harness, test suite