TestCheckNull (Function)

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Operating mode
Managing assertions

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TestCheckNull (Function)

In french: TestVérifieNull

Checks whether an expression is Null in assertive programming and in automatic test mode.

Note: This function is equivalent to dbgCheckNull.

Example

// If FindCustomer is a procedure used to find a customer identified by its name and that returns
// the CCustomer object corresponding to the customer if the customer is known and Null otherwise
// A customer who already exists must not be added
TestCheckNull(FindCustomer(CustomerName), "Customer '%1' is already known", CustomerName)
// Adds the customer
AddCustomer(CustomerName)

Syntax

TestCheckNull(<Expression> [, <Comments> [, <Parameter 1> [... [, <Parameter N>]]]])

<Expression>: Character string (with or without quotes)

Expression that must be checked.

<Comments>: Character string (with quotes)

Character string in the format defined by StringBuild.

<Parameter 1>: Any type

First parameter expected by <Comments>.

<Parameter N>: Any type

Nth parameter expected by <Comments>.

Remarks

Operating mode

When the expression is not Null:

in automatic test mode, an error is added into the status report of the test (equivalent to TestWriteResult).
in manual test mode, an assertion is displayed (equivalent to dbgAssert).
in runtime mode, an assertion is displayed if the assertions have been enabled (equivalent to dbgAssert).

When running an application, the expression is not evaluated if the assertions are not enabled.

dbgOnError allows you to automatically start a WLanguage procedure used to retrieve the comment linked to the error.

Managing assertions

The messages of TestCheckNull will be written into the ADB log (at "Assert" level). See Managing ADB logs for more details.

Component : wd250.dll