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Version 3.1.2 chokes (fails hard) on parsing real-world user agent that previous versions could parse successfully #95
Description
Thanks for building and maintaining this great library! I upgraded to the latest release and found an issue parsing some
Repro code:
HttpUserAgentParser.Parse("Mozilla/5.0 (Linux; U; Android 13; Infinix X6836 Build/TP1A.220624.014; wv) AppleWebKit/537.36 (KHTML, like Gecko) Version/4.0 Chrome/145.0.7632.120 Mobile Safari/537.36 OPR/98.0.2254.81553");
On 3.1.2, this fails with:
System.ArgumentOutOfRangeException: Specified argument was out of the range of valid values.
at MyCSharp.HttpUserAgentParser.HttpUserAgentParser.GetBrowser(String userAgent) in /home/runner/work/HttpUserAgentParser/HttpUserAgentParser/src/HttpUserAgentParser/HttpUserAgentParser.cs:line 108
at MyCSharp.HttpUserAgentParser.HttpUserAgentParser.Parse(String userAgent) in /home/runner/work/HttpUserAgentParser/HttpUserAgentParser/src/HttpUserAgentParser/HttpUserAgentParser.cs:line 30
On 3.0.28, this works and gives us MobileDeviceType: Android, Name: Opera, Platform: Android, Version: 98.0.2254.81553
Other examples that fail on 3.1.2 but not 3.0.28:
Mozilla/5.0 (Linux; U; Android 13; Hisense U53 Build/TP1A.220624.014; wv) AppleWebKit/537.36 (KHTML, like Gecko) Version/4.0 Chrome/145.0.7632.79 Mobile Safari/537.36 OPR/98.0.2254.81553Mozilla/5.0 (Linux; Android 10; MED-LX9) AppleWebKit/537.36 (KHTML, like Gecko) Chrome/110.0.5481.192 Mobile Safari/537.36 OPR/74.0.3922.71152Mozilla/5.0 (Linux; U; Android 13; Infinix X6526 Build/TP1A.220624.014; wv) AppleWebKit/537.36 (KHTML, like Gecko) Version/4.0 Chrome/145.0.7632.79 Mobile Safari/537.36 OPR/97.1.2254.80849
Activity
BenjaminAbt commentedon Mar 5, 2026
Thank you. I added all of yours and current listed Opera User Agents to the test suite and fixed the issue.
Because it's an hot path issue, I have unlisted 3.1.2 and released 3.1.3
mikethea1 commentedon Mar 6, 2026
@BenjaminAbt I ran 3.1.3 against the set of user agents that originally hit the error and I now see no failures. Really appreciate the quick fix!