As we have seen, a JQL function allows us to define custom expressions or searchers. JIRA has a set of built-in JQL functions, the details of which can be found at http://confluence.atlassian.com/display/JIRA/Advanced+Searching#AdvancedSearching-FunctionsReference. In this recipe, we will look at writing a new JQL function.
JQL functions provide a way for values within a JQL query to be calculated at runtime. It takes optional arguments and produces results based on the arguments at runtime.
In our example, let us consider creating a function, projects(), which can take a list of project keys and return all the issues in the supplied projects, for example, project in projects("TEST", "DEMO").
This will be equivalent to project in ("TEST","DEMO"), and also to project = "TEST" OR project = "DEMO".
We are introducing this new function just for the sake of this recipe. A simple function makes it easier to explain the concepts without worrying much about the logic of what it...