fix: replace substr with mb_substr in Str::beforeLast to ensure multibyte string compatibility and correct TeamCity test names for datasets in "describe" blocks

[smirok]

What:

• Bug Fix
• New Feature

Description:

Problem:

When running Pest tests with --teamcity flag inside a describe block with datasets, the last 2 characters of the test suite name are incorrectly cut off.

Root Cause:

The Str::beforeLast() method in src/Support/Str.php has a byte/character position mismatch bug:

public static function beforeLast(string $subject, string $search): string
{
    // ...
    $pos = mb_strrpos($subject, $search);  // Returns CHARACTER position
    // ...
    return substr($subject, 0, $pos);       // Expects BYTE position
}

The describe block format uses the arrow character → (U+2192), which is:

• 1 character in length
• 3 bytes in UTF-8 encoding

When mb_strrpos finds the position of with data set in a string like my_block → my_test with data set "1", it returns a character position. But substr interprets this as a byte position, causing a 2-byte offset (3 bytes for → minus 1 character = 2 bytes difference).

Example:

• Input: my_block → my_test with data set "1"
• Expected output: my_block → my_test
• Actual output: my_block → my_te

Solution

Change substr to mb_substr in Str::beforeLast() to ensure character-based substring operation matches the character based position from mb_strrpos.

Impact

It will allow to support navigation for such tests from the Test Results tool window in PhpStorm to source code in the file.