1 files changed, 80 insertions, 0 deletions
diff --git a/scripts/linters/src/Linters/NoStdCollectionsMaps.php b/scripts/linters/src/Linters/NoStdCollectionsMaps.php
new file mode 100644
index 00000000..c2f9c32e
--- /dev/null
+++ b/scripts/linters/src/Linters/NoStdCollectionsMaps.php
@@ -0,0 +1,80 @@
+<?php
+
+declare(strict_types=1);
+
+namespace Shirabe\Lint\Linters;
+
+use Shirabe\Lint\Linter;
+use Shirabe\Lint\Support\FileFinder;
+use Shirabe\Lint\Support\Paths;
+
+final class NoStdCollectionsMaps implements Linter
+{
+    private const BANNED_MAP_NAMES = ['HashMap', 'HashSet', 'BTreeMap', 'BTreeSet'];
+
+    public function name(): string
+    {
+        return 'no_std_collections_maps';
+    }
+
+    public function failureIntro(): string
+    {
+        return "Found uses of `std::collections::{HashMap, HashSet, BTreeMap, BTreeSet}`.\n"
+            . 'Use `indexmap::IndexMap` / `indexmap::IndexSet` instead:';
+    }
+
+    public function check(string $rootDir, array $excludes): array
+    {
+        $errors = [];
+
+        foreach (FileFinder::rustFiles($rootDir) as $path) {
+            $relative = Paths::relativeTo($rootDir, $path);
+            if (in_array($relative, $excludes, true)) {
+                continue;
+            }
+
+            array_push($errors, ...$this->findStdMapUsages($path, $relative));
+        }
+
+        return $errors;
+    }
+
+    /** @return list<string> */
+    private function findStdMapUsages(string $path, string $relative): array
+    {
+        $errors = [];
+
+        foreach (file($path) as $idx => $raw) {
+            $code = explode('//', $raw, 2)[0];
+
+            if (preg_match_all('/\bstd::collections::(HashMap|HashSet|BTreeMap|BTreeSet)\b/', $code, $m)) {
+                foreach ($m[1] as $name) {
+                    $errors[] = "{$relative}:" . ($idx + 1) . ": use of `std::collections::{$name}` (use `indexmap::" . self::indexmapReplacement($name) . '` instead)';
+                }
+            }
+
+            if (preg_match_all('/\bstd::collections::\{([^}]*)\}/', $code, $m)) {
+                foreach ($m[1] as $group) {
+                    foreach (explode(',', $group) as $entry) {
+                        $name = preg_split('/\s+as\s+/', trim($entry))[0];
+                        if (!in_array($name, self::BANNED_MAP_NAMES, true)) {
+                            continue;
+                        }
+                        $errors[] = "{$relative}:" . ($idx + 1) . ": import of `std::collections::{$name}` (use `indexmap::" . self::indexmapReplacement($name) . '` instead)';
+                    }
+                }
+            }
+        }
+
+        return array_values(array_unique($errors));
+    }
+
+    private static function indexmapReplacement(string $name): string
+    {
+        return match ($name) {
+            'HashMap', 'BTreeMap' => 'IndexMap',
+            'HashSet', 'BTreeSet' => 'IndexSet',
+            default => throw new \LogicException("unexpected map name: {$name}"),
+        };
+    }
+}