[FREEMARKER-208] Allow to provide a specific locale for lower_case / upper_case

• Type: Improvement
• Status: Closed
• Priority: Minor
• Resolution: Implemented
• Fix Version/s: 2.3.32
• Assignee: Dániel Dékány
• Reporter: Florian Motteau
• Created: 19/Jul/22 15:17
• Updated: 16/Jan/23 08:38
• Resolved: 18/Dec/22 19:22

Description

lower_case and upper_case filters rely on toLowerCase / toUpperCase methods. They use the current environment locale as first and only parameter for these methods.

https://github.com/apache/freemarker/blob/201533eb7c15e3cfc55b38da37f730a3492bec0f/src/main/java/freemarker/core/BuiltInsForStringsBasic.java#L433

In rare cases, we might want to provide a specific/fixed locale, to avoid some weird problems, such as the Turkish/Azeri dotless i problem :

// lowercasing an uppercase i, using turkish locale
System.out.println("I".toLowerCase(new Locale("tr", "TR")));

...will output "ı" (which is a dotless "i").

We faced this problem in OFBiz (https://issues.apache.org/jira/browse/OFBIZ-12660), and although we can fix this for our specific use case, it may be a good idea to be able to pass a locale (which sould defaults to the environment locale if not provided) as parameter for lower_case and upper_case :

myVar?lower_case("en", "EN") 

Issue Links

• links to: Related Baeldung post
• links to: Related SO post