The CSV importer fails to import issues that contain ${variables}. For instance, trying to import this CSV:

summary
"${foo} ${foo}"

with a straightforward mapping file:

existingprojectkey = TP
importsingleproject = false
importexistingproject = true
mapfromcsv = false
field.summary = summary
field.bugzilla = customfield_bugzilla
field.description = description
user.email.suffix = @atlassian.com

results in:

Exception in thread "Thread-11" java.lang.IllegalStateException: infinite loop in property interpolation of ${foo} ${foo}: foo->foo
at org.apache.commons.configuration.AbstractConfiguration.interpolateHelper(AbstractConfiguration.java:225)
at org.apache.commons.configuration.AbstractConfiguration.interpolate(AbstractConfiguration.java:161)
at org.apache.commons.configuration.SubsetConfiguration.interpolate(SubsetConfiguration.java:233)
at org.apache.commons.configuration.SubsetConfiguration.interpolate(SubsetConfiguration.java:238)
at org.apache.commons.configuration.AbstractConfiguration.getString(AbstractConfiguration.java:970)
at com.atlassian.jira.imports.csv.PropertiesCsvMapper.getValue(PropertiesCsvMapper.java:97)
at com.atlassian.jira.imports.csv.HeaderRowCsvMapper.mapDataRow(HeaderRowCsvMapper.java:67)
at com.atlassian.jira.imports.csv.MindProdCsvProvider.getNextLine(MindProdCsvProvider.java:90)
at com.atlassian.jira.imports.csv.CsvDataBean.populateCache(CsvDataBean.java:119)
at com.atlassian.jira.imports.csv.CsvDataBean.getUsers(CsvDataBean.java:241)
at com.atlassian.jira.imports.importer.impl.DefaultJiraDataImporter.importUsers(DefaultJiraDataImporter.java:160)
at com.atlassian.jira.imports.importer.impl.DefaultJiraDataImporter.doImport(DefaultJiraDataImporter.java:57)
at com.atlassian.jira.imports.importer.impl.ImporterThread.run(ImporterThread.java:16)

The CSV importer freezes at this point, and no further issues are imported.