JosefNemec/Playnite · warning · Exception

Uknown file exclusion configuration.

Error message

Uknown file exclusion configuration.

What it means

Thrown as a dead-code defensive guard in GetFileExclusionMatches. Because the preceding branches are if(MatchByRegex) / else if(Absolute) / else if(!Absolute), the final else is logically unreachable — every ScanExclusion is either absolute or not. This throw exists to catch a logic regression rather than a real runtime input; it fires only if the Absolute flag semantics become non-boolean or branch ordering is broken.

Source

Thrown at source/Playnite/Emulators/Scanner.cs:483

                    matches.AddMissing(match);
                }
                else if (excFile.Absolute)
                {
                    var match = files.FirstOrDefault(a => a.Equals(excFile.Path, StringComparison.OrdinalIgnoreCase));
                    if (match != null)
                    {
                        matches.AddMissing(match);
                    }
                }
                else if (!excFile.Absolute)
                {
                    var comp = excFile.Path.PrefixWithDirSeparator();
                    var match = files.Where(a => a.EndsWith(comp, StringComparison.OrdinalIgnoreCase));
                    matches.AddMissing(match);
                }
                else
                {
                    throw new Exception("Uknown file exclusion configuration.");
                }
            }

            return matches;
        }

        public static List<string> GetDirectoryExclusionMatches(List<string> dirs, List<ScanExclusion> exclusions)
        {
            var matches = new List<string>();
            foreach (var excDir in exclusions)
            {
                if (excDir.MatchByRegex)
                {
                    // exclusion parser already appends root path if needed so same match can be done here
                    // for any level match and absolute path match
                    var match = dirs.Where(a => Regex.IsMatch(a.TrimEnd(Paths.DirectorySeparators), excDir.Path, RegexOptions.IgnoreCase));
                    matches.AddMissing(match);
                }

View on GitHub (pinned to 5911f4e964)

Solutions

1. No action needed for callers — this branch is unreachable with boolean Absolute.
2. If encountered during development, audit recent edits to ScanExclusion.Absolute and the if/else chain ordering in GetFileExclusionMatches.
3. Consider removing the dead branch or converting it to an assertion to clarify intent.

Example fix

// before
else if (!excFile.Absolute) { ... }
else { throw new Exception("Uknown file exclusion configuration."); }

// after — collapse the redundant else-if into a final else
else { var comp = excFile.Path.PrefixWithDirSeparator(); matches.AddMissing(files.Where(a => a.EndsWith(comp, StringComparison.OrdinalIgnoreCase))); }

// Unreachable for boolean Absolute; no caller validation needed. For safety, assert the type.
Debug.Assert(excFile.Absolute is bool, "ScanExclusion.Absolute must be boolean");

When it happens

Trigger: Theoretically unreachable for any boolean Absolute value: the !Absolute branch (line 475) already covers the false case, so the trailing else can never evaluate. Would only trigger if Absolute were changed to a nullable/non-bool type or the branch conditions were reordered incorrectly.

Common situations: Not hit in normal operation. A maintainer refactoring the exclusion logic could accidentally make it reachable; otherwise it is vestigial defensive code.

Related errors

• Emulator not found.
• No emulator profile specified.
• Assigned custom emulator profile not found.
• Assigned built-in emulator profile not found.
• Assigned built-in emulator profile definition not found.

AI-assisted analysis of JosefNemec/Playnite@5911f4e964 (2026-08-13). Data as JSON: /api/errors/33b0ec468ac178d5. Report an issue: GitHub.