JExample

Active context can be used to snapshot object and avoid cloning. Perfect for JExample-like unit tests:

testSuiteFailCtx

    | queue  |

    self doSuite: [
        queue := self testCreation.
        queue := self testAdd: queue.
        queue := self testAdd2: queue.

        TestContext do: [
            queue := self testDelete2: queue.
            queue := self testFail: queue.
            queue := self testDelete1: queue.
        ].

        TestContext do: [
            queue := self testClear: queue.
        ].
    ].

Running the test suite prints something like:

Test: testCreation
Test: testCreation
Test: testAdd:
Test: testAdd2:
Test: testDelete2:
Test: testFail:
Failure occured
Test: testClear:
Test suite [success=6, failure=1]

The context is a regular class, so in this case we also override the do: method to deal with faulty tests.

TestContext>>do: aBlock

    [ ^ super do: aBlock ] on: Error do: [ Transcript show: 'Failure occured'; cr. ].

TestContext>>transitionKeysFrom: instVarFrom keysTo: instVarTo

super transitionKeysFrom: instVarFrom  keysTo: instVarTo .

TestContext>>transitionKeysTo: instVarTo keysFrom: instVarFrom

instVarFrom at: 'class' put: (instVarTo at: 'class').