Problem

The JSON generator was incorrectly parsing MIME type files that contain multiple tab delimiters between the MIME type and file extensions. This is a common format in Apache's mime.types file.

For example, the line:

application/vnd.acucorp				atc acutc

Was incorrectly generating:

"acutc": "application/vnd.acucorp\t\t\t\tatc"

Instead of the correct output:

"acutc": "application/vnd.acucorp",
"atc": "application/vnd.acucorp"

This resulted in MIME type values containing tab characters and partial extension names, and missing entries for extensions that should have been parsed.

Root Cause

The bug was in the ParseMimeTypesListing method in ManagedCode.MimeTypes.Sync/Program.cs at line 148:

var parts = line.Split(' ', '\t', StringSplitOptions.RemoveEmptyEntries | StringSplitOptions.TrimEntries);

This code appears to split on both space and tab characters, but actually uses an incorrect method signature. The Split(char, char, StringSplitOptions) overload doesn't exist - instead, this resolves to Split(char separator, int count, StringSplitOptions options) where the second char parameter is implicitly converted to an int count/limit parameter.

As a result, the split only used space as a delimiter, leaving all tab characters in the first part of the split result.

Solution

Changed to use the correct Split signature with a character array:

var parts = line.Split(new[] { ' ', '\t' }, StringSplitOptions.RemoveEmptyEntries | StringSplitOptions.TrimEntries);

This ensures both space and tab characters are properly recognized as delimiters when parsing MIME type files.

Testing

• All 68 existing tests pass
• Manually verified the fix correctly parses lines with multiple consecutive tabs
• Both extensions (atc and acutc) are now correctly mapped to the same MIME type
• MIME type values no longer contain tab characters or partial extension names

Additional Changes

• Added *.trx to .gitignore to exclude test result files from version control

Fixes the issue reported in the original bug report referencing PR #4.

Fixes #5

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