Comparing trees

TreeDiff compares paths in two trees and classifies them as added, removed, or unchanged.

<?php
use Alto\Tree\Diff\TreeDiff;
use Alto\Tree\TreeBuilder;

$before = TreeBuilder::fromPaths([
    'project/src/App.php',
    'project/README.md',
], 'project');

$after = TreeBuilder::fromPaths([
    'project/src/App.php',
    'project/tests/AppTest.php',
], 'project');

$diff = TreeDiff::compare($before, $after);

echo $diff->getSummary(); // +2 -1

Directories introduced by new paths count as additions. The root itself is not included in the comparison.

Inspect getAdded(), getRemoved(), and getUnchanged() for maps keyed by path. Count methods and hasChanges() provide quick decisions.

Render the result

<?php
use Alto\Tree\Diff\DiffPrinter;

$printer = new DiffPrinter();

echo $printer->print($diff);
echo $printer->printSummary($diff);
echo $printer->printUnified($diff, 'before', 'after');

print() accepts show_unchanged => true when the complete path comparison is needed. Unified output is a path-level report, not a textual patch that can be applied to a filesystem.