Raise PHPStan to level 10

phpstan.neon

@@ -1,5 +1,5 @@
 parameters:
-    level: 8
+    level: 10
     treatPhpDocTypesAsCertain: false
     paths:
         - src

src/Apply/DryRun.php

@@ -43,7 +43,7 @@ public static function generate(
                 return "'" . str_replace(
                     ['\\', "'", "\0", "\n", "\r"],
                     ['\\\\', "''", '\\0', '\\n', '\\r'],
-                    (string) $val,
+                    is_bool($val) ? ($val ? '1' : '0') : (string) $val,
                 ) . "'";
             }, $sql);
             $output[] = (string) $replaced;

src/Apply/SqlGenerator.php

@@ -19,7 +19,7 @@ final class SqlGenerator
      * Generate SQL statements for all operations.
      *
      * @param array<string, list<string>> $fkDependencies FK dependency map (child to parents).
-     * @return list<array{sql: string, params: list<mixed>}>
+     * @return list<array{sql: string, params: list<scalar|null>}>
      */
     public static function generate(
         MergeResult $result,
@@ -75,7 +75,7 @@ public static function generate(
 
     /**
      * @param \Closure(string): string $q Identifier quoter.
-     * @return array{sql: string, params: list<mixed>}
+     * @return array{sql: string, params: list<scalar|null>}
      */
     private static function generateInsert(MergeOperation $op, \Closure $q): array
     {
@@ -95,7 +95,7 @@ private static function generateInsert(MergeOperation $op, \Closure $q): array
 
     /**
      * @param \Closure(string): string $q Identifier quoter.
-     * @return array{sql: string, params: list<mixed>}|null
+     * @return array{sql: string, params: list<scalar|null>}|null
      */
     private static function generateUpdate(MergeOperation $op, ?Snapshot $base, \Closure $q): ?array
     {
@@ -135,7 +135,7 @@ private static function generateUpdate(MergeOperation $op, ?Snapshot $base, \Clo
 
     /**
      * @param \Closure(string): string $q Identifier quoter.
-     * @return array{sql: string, params: list<mixed>}
+     * @return array{sql: string, params: list<scalar|null>}
      */
     private static function generateDelete(MergeOperation $op, ?Snapshot $base, \Closure $q): array
     {

src/CellMerge/CellMergeResult.php

@@ -11,17 +11,17 @@
 {
     private function __construct(
         public bool $clean,
-        public mixed $value,
+        public string|int|float|bool|null $value,
         public int $conflicts,
     ) {
     }
 
-    public static function resolved(mixed $value): self
+    public static function resolved(string|int|float|bool|null $value): self
     {
         return new self(true, $value, 0);
     }
 
-    public static function conflict(mixed $oursValue, int $conflicts = 1): self
+    public static function conflict(string|int|float|bool|null $oursValue, int $conflicts = 1): self
     {
         return new self(false, $oursValue, $conflicts);
     }

src/CellMerge/CellMerger.php

@@ -19,5 +19,9 @@ interface CellMerger
      * Return CellMergeResult::resolved() if the merge is clean,
      * or CellMergeResult::conflict() if it cannot be resolved.
      */
-    public function merge(mixed $base, mixed $ours, mixed $theirs): CellMergeResult;
+    public function merge(
+        string|int|float|bool|null $base,
+        string|int|float|bool|null $ours,
+        string|int|float|bool|null $theirs,
+    ): CellMergeResult;
 }

src/CellMerge/JsonCellMerger.php

@@ -19,8 +19,11 @@
  */
 final class JsonCellMerger implements CellMerger
 {
-    public function merge(mixed $base, mixed $ours, mixed $theirs): CellMergeResult
-    {
+    public function merge(
+        string|int|float|bool|null $base,
+        string|int|float|bool|null $ours,
+        string|int|float|bool|null $theirs,
+    ): CellMergeResult {
         $baseObj = self::decode($base);
         $oursObj = self::decode($ours);
         $theirsObj = self::decode($theirs);
@@ -101,6 +104,10 @@ private static function decode(mixed $value): mixed
             return null;
         }
 
+        if (!is_scalar($value)) {
+            return null;
+        }
+
         try {
             return json_decode((string) $value, true, 512, JSON_THROW_ON_ERROR);
         } catch (\JsonException) {

src/CellMerge/OpaqueCellMerger.php

@@ -10,8 +10,11 @@
  */
 final class OpaqueCellMerger implements CellMerger
 {
-    public function merge(mixed $base, mixed $ours, mixed $theirs): CellMergeResult
-    {
+    public function merge(
+        string|int|float|bool|null $base,
+        string|int|float|bool|null $ours,
+        string|int|float|bool|null $theirs,
+    ): CellMergeResult {
         return CellMergeResult::conflict($ours);
     }
 }

src/CellMerge/TextCellMerger.php

@@ -12,8 +12,11 @@
  */
 final class TextCellMerger implements CellMerger
 {
-    public function merge(mixed $base, mixed $ours, mixed $theirs): CellMergeResult
-    {
+    public function merge(
+        string|int|float|bool|null $base,
+        string|int|float|bool|null $ours,
+        string|int|float|bool|null $theirs,
+    ): CellMergeResult {
         $result = ThreeWayMerge::merge(
             (string) ($base ?? ''),
             (string) ($ours ?? ''),

src/Diff/ColumnDiff.php

@@ -11,8 +11,8 @@
 {
     public function __construct(
         public string $column,
-        public mixed $oldValue,
-        public mixed $newValue,
+        public string|int|float|bool|null $oldValue,
+        public string|int|float|bool|null $newValue,
     ) {
     }
 }

src/Diff/Differ.php

@@ -92,8 +92,8 @@ private function diffTable(
     }
 
     /**
-     * @param array<string, mixed> $baseRow
-     * @param array<string, mixed> $currentRow
+     * @param array<string, scalar|null> $baseRow
+     * @param array<string, scalar|null> $currentRow
      * @return list<ColumnDiff>
      */
     private function diffColumns(array $baseRow, array $currentRow): array
@@ -116,7 +116,7 @@ private function diffColumns(array $baseRow, array $currentRow): array
     /**
      * Compare two values, treating NULL as a distinct value.
      */
-    public static function valuesEqual(mixed $a, mixed $b): bool
+    public static function valuesEqual(string|int|float|bool|null $a, string|int|float|bool|null $b): bool
     {
         if ($a === null && $b === null) {
             return true;

src/Diff/RowDelete.php

@@ -12,7 +12,7 @@
     /**
      * @param string $table Table name.
      * @param string $rowKey Row identity key.
-     * @param array<string, mixed> $oldValues Column values before deletion.
+     * @param array<string, scalar|null> $oldValues Column values before deletion.
      */
     public function __construct(
         public string $table,

src/Diff/RowInsert.php

@@ -12,7 +12,7 @@
     /**
      * @param string $table Table name.
      * @param string $rowKey Row identity key.
-     * @param array<string, mixed> $values All column values.
+     * @param array<string, scalar|null> $values All column values.
      */
     public function __construct(
         public string $table,

src/Diff/RowUpdate.php

@@ -13,7 +13,7 @@
      * @param string $table Table name.
      * @param string $rowKey Row identity key.
      * @param list<ColumnDiff> $columnDiffs Per-column changes.
-     * @param array<string, mixed> $fullRow Complete current row data.
+     * @param array<string, scalar|null> $fullRow Complete current row data.
      */
     public function __construct(
         public string $table,

src/Driver/DriverFactory.php

@@ -36,6 +36,10 @@ public static function create(PDO $pdo): Driver
     {
         $pdoDriver = $pdo->getAttribute(PDO::ATTR_DRIVER_NAME);
 
+        if (!is_string($pdoDriver)) {
+            throw new \RuntimeException('Unable to determine PDO driver name.');
+        }
+
         $class = self::$drivers[$pdoDriver] ?? null;
         if ($class === null) {
             throw new \RuntimeException("Unsupported database driver: {$pdoDriver}");

src/Driver/MysqlDriver.php

@@ -55,7 +55,15 @@ public function readForeignKeys(PDO $pdo): array
 
         $deps = [];
         foreach ($stmt->fetchAll(PDO::FETCH_ASSOC) as $row) {
-            $deps[$row['TABLE_NAME']][] = $row['REFERENCED_TABLE_NAME'];
+            if (!is_array($row)) {
+                continue;
+            }
+            $tableName = $row['TABLE_NAME'] ?? null;
+            $referenced = $row['REFERENCED_TABLE_NAME'] ?? null;
+            if (!is_string($tableName) || !is_string($referenced)) {
+                continue;
+            }
+            $deps[$tableName][] = $referenced;
         }
 
         return $deps;
@@ -79,7 +87,15 @@ private function readColumns(PDO $pdo, string $db, string $table): array
 
         $columns = [];
         foreach ($stmt->fetchAll(PDO::FETCH_ASSOC) as $row) {
-            $columns[$row['COLUMN_NAME']] = $row['COLUMN_TYPE'];
+            if (!is_array($row)) {
+                continue;
+            }
+            $name = $row['COLUMN_NAME'] ?? null;
+            $type = $row['COLUMN_TYPE'] ?? null;
+            if (!is_string($name) || !is_string($type)) {
+                continue;
+            }
+            $columns[$name] = $type;
         }
 
         return $columns;
@@ -125,7 +141,15 @@ private function readUniqueKeys(PDO $pdo, string $db, string $table): array
 
         $keys = [];
         foreach ($stmt->fetchAll(PDO::FETCH_ASSOC) as $row) {
-            $keys[$row['CONSTRAINT_NAME']][] = $row['COLUMN_NAME'];
+            if (!is_array($row)) {
+                continue;
+            }
+            $constraint = $row['CONSTRAINT_NAME'] ?? null;
+            $column = $row['COLUMN_NAME'] ?? null;
+            if (!is_string($constraint) || !is_string($column)) {
+                continue;
+            }
+            $keys[$constraint][] = $column;
         }
 
         return array_values(array_map('array_values', $keys));

src/Driver/SqliteDriver.php

@@ -51,12 +51,19 @@ public function readForeignKeys(PDO $pdo): array
 
             $parents = [];
             foreach ($stmt->fetchAll(PDO::FETCH_ASSOC) as $row) {
-                $parents[] = $row['table'];
+                if (!is_array($row)) {
+                    continue;
+                }
+                $parent = $row['table'] ?? null;
+                if (!is_string($parent)) {
+                    continue;
+                }
+                $parents[] = $parent;
             }
 
-            $parents = array_unique($parents);
+            $parents = array_values(array_unique($parents));
             if ($parents !== []) {
-                $deps[$table] = array_values($parents);
+                $deps[$table] = $parents;
             }
         }
 
@@ -80,7 +87,15 @@ private function readColumns(PDO $pdo, string $table): array
 
         $columns = [];
         foreach ($stmt->fetchAll(PDO::FETCH_ASSOC) as $row) {
-            $columns[$row['name']] = strtolower($row['type'] ?: 'text');
+            if (!is_array($row)) {
+                continue;
+            }
+            $name = $row['name'] ?? null;
+            $type = $row['type'] ?? null;
+            if (!is_string($name)) {
+                continue;
+            }
+            $columns[$name] = strtolower(is_string($type) && $type !== '' ? $type : 'text');
         }
 
         return $columns;
@@ -98,8 +113,17 @@ private function readPrimaryKey(PDO $pdo, string $table): array
 
         $pkColumns = [];
         foreach ($stmt->fetchAll(PDO::FETCH_ASSOC) as $row) {
-            if ((int) $row['pk'] > 0) {
-                $pkColumns[(int) $row['pk']] = $row['name'];
+            if (!is_array($row)) {
+                continue;
+            }
+            $pk = $row['pk'] ?? null;
+            $name = $row['name'] ?? null;
+            if (!is_numeric($pk) || !is_string($name)) {
+                continue;
+            }
+            $pkOrder = (int) $pk;
+            if ($pkOrder > 0) {
+                $pkColumns[$pkOrder] = $name;
             }
         }
 
@@ -120,22 +144,38 @@ private function readUniqueKeys(PDO $pdo, string $table): array
 
         $uniqueKeys = [];
         foreach ($stmt->fetchAll(PDO::FETCH_ASSOC) as $index) {
-            if ((int) $index['unique'] !== 1) {
+            if (!is_array($index)) {
+                continue;
+            }
+            $unique = $index['unique'] ?? null;
+            if (!is_numeric($unique) || (int) $unique !== 1) {
                 continue;
             }
 
             if (($index['origin'] ?? null) === 'pk') {
                 continue;
             }
 
-            $colStmt = $pdo->query("PRAGMA index_info(" . $this->quoteIdentifier($index['name']) . ")");
+            $indexName = $index['name'] ?? null;
+            if (!is_string($indexName)) {
+                continue;
+            }
+
+            $colStmt = $pdo->query("PRAGMA index_info(" . $this->quoteIdentifier($indexName) . ")");
             if ($colStmt === false) {
                 continue;
             }
 
             $cols = [];
             foreach ($colStmt->fetchAll(PDO::FETCH_ASSOC) as $col) {
-                $cols[] = $col['name'];
+                if (!is_array($col)) {
+                    continue;
+                }
+                $colName = $col['name'] ?? null;
+                if (!is_string($colName)) {
+                    continue;
+                }
+                $cols[] = $colName;
             }
 
             if ($cols !== []) {

src/Filter/ColumnFilter.php

@@ -28,8 +28,8 @@ public static function ignore(array $columns): self
     /**
      * Remove ignored columns from a row.
      *
-     * @param array<string, mixed> $row
-     * @return array<string, mixed>
+     * @param array<string, scalar|null> $row
+     * @return array<string, scalar|null>
      */
     public function applyToRow(array $row): array
     {

src/Filter/RowFilter.php

@@ -9,7 +9,7 @@
  */
 final class RowFilter
 {
-    /** @var \Closure(string, array<string, mixed>): bool */
+    /** @var \Closure(string, array<string, scalar|null>): bool */
     private \Closure $predicate;
 
     private function __construct(\Closure $predicate)
@@ -20,7 +20,7 @@ private function __construct(\Closure $predicate)
     /**
      * Create a row filter from a predicate.
      *
-     * @param callable(string, array<string, mixed>): bool $predicate
+     * @param callable(string, array<string, scalar|null>): bool $predicate
      *     Receives table name and row data, returns true to include the row.
      */
     public static function create(callable $predicate): self
@@ -29,7 +29,7 @@ public static function create(callable $predicate): self
     }
 
     /**
-     * @param array<string, mixed> $row
+     * @param array<string, scalar|null> $row
      */
     public function shouldInclude(string $table, array $row): bool
     {