Insert and connect a Tester transformer into your workspace.
Click 
to set the values.
Tester transformers perform a generic test (or multiple tests at once) that can consist of any FME-allowed operands.
Operands can consist of:
attributes on your feature types
any FME function
any constant value
mathematical operations
Insert and connect a Tester transformer into your workspace.
Click to set the values.
Note: By default, the Comparison Method is set to "Automatic" which means the Tester will first try to convert the operands to numbers. If it is successful, it will compare them as numbers. If it is not successful, it will treat operands as strings. For example, when "Automatic" is chosen, it is possible that the string "4E5" will be treated as a number, which may not be desirable. To prevent this, set the Comparison Method to "String" – this ensures that the Tester will always treat the operands as strings, and will compare them as strings.
If the test is passed, the feature is output via the PASSED port. Otherwise, it is output via the FAILED port.
The results can be used to filter features based on attributes.
For this example to pass, the OWNER must equal CITY:
See an example workspace on fmepedia.