Core: TableConverter extracts child object values but not headers

Hi! I’d like to report a bug I encountered while trying out Cucumber on my freshly-converted Kotlin Android application. I’m not entirely sure if this is a bug with Cucumber or Kotlin, so I’ll let you judge.

Steps to reproduce

• Given TimeoLine.kt

data class TimeoLine (val id: String, val name: String, val direction: TimeoDirection, val networkCode: Int = 147, val color: String = "#34495E") {
    override fun toString(): String = name
}

• Given TimeoDirection.kt

data class TimeoDirection (var id: String, var name: String) {
    override fun toString(): String = "$id - $name"
}

nb: As you can see, TimeoLine contains a TimeoDirection as a property named direction

• Call DataTable.create() on a List<TimeoLine>

Expected behavior

The function returns a table that looks like this:

id	name	direction	networkCode	color
TRAM	Tram	A - Ifs Grace de Dieu	147	#ff3300
…	…	…	…	…

Observed behavior

cucumber.runtime.CucumberException: Table is unbalanced: expected 5 column(s) but found 6.
    at cucumber.api.DataTable.<init>(DataTable.java:63)
    at cucumber.runtime.table.TableConverter.createDataTable(TableConverter.java:272)
    at cucumber.runtime.table.TableConverter.toTable(TableConverter.java:258)
    at cucumber.api.DataTable.create(DataTable.java:45)
    at cucumber.api.DataTable.create(DataTable.java:31)
    at fr.outadev.android.transport.timeo.ParseStepDefinitions.iGetTheFollowingLines(ParseStepDefinitions.kt:65)
    at sun.reflect.NativeMethodAccessorImpl.invoke0(Native Method)
    at sun.reflect.NativeMethodAccessorImpl.invoke(NativeMethodAccessorImpl.java:62)
    at sun.reflect.DelegatingMethodAccessorImpl.invoke(DelegatingMethodAccessorImpl.java:43)
    at java.lang.reflect.Method.invoke(Method.java:498)
    at cucumber.runtime.Utils$1.call(Utils.java:37)
    at cucumber.runtime.Timeout.timeout(Timeout.java:13)
    at cucumber.runtime.Utils.invoke(Utils.java:31)
    at cucumber.runtime.java.JavaStepDefinition.execute(JavaStepDefinition.java:38)
    at cucumber.runtime.StepDefinitionMatch.runStep(StepDefinitionMatch.java:37)
    at cucumber.runtime.Runtime.runStep(Runtime.java:299)
    [...]

By playing a bit with the DataTable conversion, you’ll see ComplexTypeWriter extracts all the values in the object, including the members of TimeoDirection; but it only extracts the headers for the properties of the parent object (TimeoLine). It also causes some not-failing-but-extremely-confusing-behavior in diffs.

• Runtime: java-8-openjdk
• Lib version: info.cukes:cucumber-java:1.2.4

[mpkorstanje]

As it turns out I was mistaken. To achieve the desired result you have to add a converter that tells Cucumber how to present your object in a table. This should also prevent any table imbalances.

@XStreamConverter(TimeoDirectionConvertor::class)
data class TimeoDirection (var id: String, var name: String) {
    override fun toString(): String = "$id - $name"
}

class TimeoDirectionConvertor : SingleValueConverter {

    override fun toString(p0: Any?): String = p0.toString()

    override fun fromString(p0: String?): Any = {
        val (id, name) = p0!!.split(" - ");
        TimeoDirection(id, name)
    }

    override fun canConvert(p0: Class<*>?): Boolean = TimeoDirection::class.java.isAssignableFrom(p0)
}

[lock[bot]]

This thread has been automatically locked since there has not been any recent activity after it was closed. Please open a new issue for related bugs.