Multi-instance collection expression is invoked with inconsistent delegate execution state

[ThorbenLindhauer]

This issue was imported from JIRA:

Field	Value
JIRA Link	CAM-5358
Reporter	@ThorbenLindhauer
Has restricted visibility comments	true

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Current behavior:

• For a multi-instance activity with a collection expression and an element variable, the collection expression is invoked n + 1 times. Once to determine the number of iterations, and n times to determine the element variable value for every iteration
• It is possible to use the execution as a variable in the collection expression, e.g. $\{myBean.resolveCollection(execution)\}.
• for the invocations that determine the element variable, the execution is not in a state that the DelegateExecution interface provides. For example, the method #getCurrentActivityId returns null

Expected behavior:

• All methods in the DelegateExecution interface can be used when resolving a collection expression

Failing test case: 8d7a4e0

Solution ideas:

1. Invoke collection expression only once and store the collection somewhere to iterate over it (e.g. next to the multi-instance variables). Downside: collections must be serializable
2. Make sure the executions are properly initialized before the collection expression is invoked

Links:

• is depended on by https://jira.camunda.com/browse/SUPPORT-2084
• is related to https://jira.camunda.com/browse/CAM-7304

[ThorbenLindhauer]

This comment was imported from JIRA and written by user DY4BDpm

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Sorry for not having a Github PR

This is a Patch, based on the current master branch.

passing new tests are (class MultiInstanceTest):
testParallelUserTasksBasedOnCollectionExpression
testSequentialSubProcessOnCollectionExpression

<^FixCAM5358.patch>

[ThorbenLindhauer]

This comment was imported from JIRA and written by user YqDPaDV

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This pseudonym name was generated based on the user name in JIRA to protect the personal data of our JIRA users. You can use this identifier to search for issues by the same reporter.

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Ok, this patch is obsolete; it uses fields.
The collection should be persisted to the DB probably.
(I have no permission to delete the attachment)