Your first tcltests

# If you save this source as, for example, "my_first.test", then execute
# "tclsh my_first.test", the output will be something like
#    "==== intro-2 This illustrates how something goes wrong. FAILED
#    ==== Contents of test case:

#        expr 3 * 5

#    ---- Result was:
#    15
#    ---- Result should have been (exact matching):
#    16
#    ==== intro-2 FAILED"

    package require tcltest 2.0
    namespace import ::tcltest::*

    test intro-1 {This is as simple as it gets.} {
        expr 3 * 5
    } 15

    test intro-2 {This illustrates how something goes wrong.} {
        expr 3 * 5
    } 16

    test intro-3 {It's very important to validate responses when
         things go wrong.} -body {
        expr 3 / 0
    } -returnCodes error -result {divide by zero}

    test intro-4 {Tcltest, especially with 2.0, is quite powerful 
    and flexible.  Part of the reason it can be puzzling on first
    encounter is that there are typically several different styles
    to write any single test.  Two important choices are whether:  
    the specification is written as a list of clause-pairs, or a
    list of list of clause pairs; and how to leverage tcltest's
    result comparison.  Here's an example, due to Don, that
    illustrates possibilities ...} {
         -result 1
         -body {
             # Complicated calculations
         # if [something_wrong] {error xxx}
         # Still other computations, including logic ...
             return 1

    # Next up:  pattern-matching on results.

    # To see test statistics (Total/Passed/Skipped/Failed), best put this line in the end:

[TODO: Briefly summarize the benefits of tcltest.]

escargo 9 Aug 2005 - I found it to be useful to start my test files slightly differently.

 package require tcltest 2.0
 namespace import -force ::tcltest::*

The reason is that I keep a tclsh running, and then repeated source the test file as I make changes to my source code file and my test file. This way I don't get complaints about commands already being defined.

Here's a comp.lang.tcl message posted by RS during Feb, 2007 regarding how to get started writing tcltest tests:

> So, if the tests and the code to be tested are completely separate, how do you test the procedures?

By calling them :)

#-- Example.tcl:

 proc add {a b} {expr {$a+$b}}
 proc mul {a b} {expr {$a*$b}}

#-- Example.test:

 package require tcltest
 namespace import tcltest::*
 source Example.tcl

 test add-1 {simple addition} {add 3 4} 7
 test mul-1 {simple multiplication} {mul 3 4} 12

#-- One can also test the testing interactively:

 % test mul-1 {simple multiplication} {mul 3 4} 12
 % test mul-1x {simple multiplication} {mul 3 4} 13

 ==== mul-1x simple multiplication FAILED
 ==== Contents of test case:
 mul 3 4
 ---- Result was:
 ---- Result should have been (exact matching):
 ==== mul-1x FAILED