Thanks Pitinan. We would need to determine the IDNA behavior in a conversion tool and the browser. To that effect, could you ask your colleague to try the below examples. (He/She needs to copy and paste the Input strings into the tool and URL address bars, and register the output string for each test). @Mats Dufberg Provided their machines are set up with Turkish locale, are we missing any other test case? IDNA conversion https://www.punycoder.com/ User InputCopy and Paste into “Text” box, then “Convert to Punycode”zilzılZİLZIL Output Register output string in “Punycode” box Browser Behavior (repeat for Chrome, Firefox and Safari/Edge) User InputCopy and Paste in URL address Barzil.test zıl.testZİL.testZIL.test Output URL BarRegister returned label in address bar Thanks, Dennis From: Pitinan Kooarmornpatana <pitinan.koo@icann.org> Date: Friday, May 15, 2020 at 4:36 PM To: Mats Dufberg <mats.dufberg@internetstiftelsen.se>, Dennis Tan Tanaka <dtantanaka@verisign.com>, "Latingp@icann.org" <Latingp@icann.org> Subject: [EXTERNAL] Re: [Latingp] Handling of down casing of I-dotted in Turkish locale Dear all, Please find attached test case and the results. 1. test case file (test case.xlsx) 2. test result using Turkish locale (testcase-turkishlocale.xlsx) 3. test result using en_US local (test case-en_US-locale.xlsx) The test result for Turkish locale was done by someone in Turkey who use Turkish locale. The result for case folding seems to be stable both up and down. The test result for en_US was done by me and it cannot produce original dotless I after a round-folding. I understand that this due to the absence of CAPITAL LETTER I WITH DOT ABOVE in en-US locale. Kindly let us know if there is any further queries. Regards, Pitinan From: Latingp <latingp-bounces@icann.org> on behalf of Mats Dufberg <mats.dufberg@internetstiftelsen.se> Date: Friday, May 15, 2020 at 05:13 To: "Tan Tanaka, Dennis" <dtantanaka@verisign.com>, "Latingp@icann.org" <Latingp@icann.org> Subject: Re: [Latingp] Handling of down casing of I-dotted in Turkish locale

If I understand this correctly, when we test the IDNA behavior of the uppercase string in a Turkish setting we should see the behavior described in the second part.

That is my interpretation too. I will try to test some generic tool with Turkish locale (tr_TR.UTF-8) set. Mats --- Mats Dufberg mats.dufberg@internetstiftelsen.se Technical Expert Internetstiftelsen (The Swedish Internet Foundation) Mobile: +46 73 065 3899 https://internetstiftelsen.se/ From: "Tan Tanaka, Dennis" <dtantanaka@verisign.com> Date: Thursday, 14 May 2020 at 23:19 To: Mats Dufberg <mats.dufberg@internetstiftelsen.se>, ICANN Latin GP <Latingp@icann.org> Subject: Re: [Latingp] Handling of down casing of I-dotted in Turkish locale There are two set of rules, one for non-Turkish # Preserve canonical equivalence for I with dot. Turkic is handled below. 0130; 0069 0307; 0130; 0130; # LATIN CAPITAL LETTER I WITH DOT ABOVE And another for Turkish # Turkish and Azeri # I and i-dotless; I-dot and i are case pairs in Turkish and Azeri # The following rules handle those cases. 0130; 0069; 0130; 0130; tr; # LATIN CAPITAL LETTER I WITH DOT ABOVE 0130; 0069; 0130; 0130; az; # LATIN CAPITAL LETTER I WITH DOT ABOVE # When lowercasing, remove dot_above in the sequence I + dot_above, which will turn into i. # This matches the behavior of the canonically equivalent I-dot_above 0307; ; 0307; 0307; tr After_I; # COMBINING DOT ABOVE 0307; ; 0307; 0307; az After_I; # COMBINING DOT ABOVE # When lowercasing, unless an I is before a dot_above, it turns into a dotless i. 0049; 0131; 0049; 0049; tr Not_Before_Dot; # LATIN CAPITAL LETTER I 0049; 0131; 0049; 0049; az Not_Before_Dot; # LATIN CAPITAL LETTER I # When uppercasing, i turns into a dotted capital I 0069; 0069; 0130; 0130; tr; # LATIN SMALL LETTER I 0069; 0069; 0130; 0130; az; # LATIN SMALL LETTER I # Note: the following case is already in the UnicodeData.txt file. # 0131; 0131; 0049; 0049; tr; # LATIN SMALL LETTER DOTLESS I If I understand this correctly, when we test the IDNA behavior of the uppercase string in a Turkish setting we should see the behavior described in the second part. -Dennis From: Latingp <latingp-bounces@icann.org> on behalf of Mats Dufberg <mats.dufberg@internetstiftelsen.se> Date: Thursday, May 14, 2020 at 4:27 PM To: ICANN Latin GP <Latingp@icann.org> Subject: [EXTERNAL] [Latingp] Handling of down casing of I-dotted in Turkish locale The link below goes to the file in the Unicode database that handles the special casing rules for i etc in Turkish and Azerian (sp?). The relevant section is the last section of the file. https://unicode.org/Public/UNIDATA/SpecialCasing.txt [secure-web.cisco.com] --- Mats Dufberg mats.dufberg@internetstiftelsen.se Technical Expert Internetstiftelsen (The Swedish Internet Foundation) Mobile: +46 73 065 3899 https://internetstiftelsen.se/