Improve type safety in nullable detection and comparisons (#1004)

* Improve type safety in nullable detection and comparisons

- Fix strpos() casting bug in ColumnParser - (bool)strpos() returns
  false when needle is at position 0, use str_contains() instead
- Replace loose comparisons (== !=) with strict comparisons (=== !==)
  in Manager.php for version and breakpoint checks

* Cast breakpoint to int for cross-database compatibility

PostgreSQL and SQL Server return boolean columns as strings or actual
booleans instead of integers, causing strict equality checks to fail.

Author: dereuromark

src/Migration/Manager.php

@@ -461,7 +461,7 @@ public function migrate(?int $version = null, bool $fake = false, ?int $count =
         if ($version === null) {
             $version = max(array_merge($versions, array_keys($migrations)));
         } else {
-            if ($version != 0 && !isset($migrations[$version])) {
+            if ($version !== 0 && !isset($migrations[$version])) {
                 $this->getIo()->out(sprintf(
                     '<comment>warning</comment> %s is not a valid version',
                     $version,
@@ -755,7 +755,7 @@ public function rollback(int|string|null $target = null, bool $force = false, bo
 
         // Check we have at least 1 migration to revert
         $executedVersionCreationTimes = array_keys($executedVersions);
-        if (!$executedVersionCreationTimes || $target == end($executedVersionCreationTimes)) {
+        if (!$executedVersionCreationTimes || $target === end($executedVersionCreationTimes)) {
             $io->out('<error>No migrations to rollback</error>');
 
             return;
@@ -795,7 +795,7 @@ public function rollback(int|string|null $target = null, bool $force = false, bo
                     }
                 }
 
-                if ($executedArray['breakpoint'] != 0 && !$force) {
+                if ((int)$executedArray['breakpoint'] !== 0 && !$force) {
                     $io->out('<error>Breakpoint reached. Further rollbacks inhibited.</error>');
                     break;
                 }
@@ -1290,7 +1290,7 @@ protected function markBreakpoint(?int $version, int $mark): void
         }
 
         $io = $this->getIo();
-        if ($version != 0 && (!isset($versions[$version]) || !isset($migrations[$version]))) {
+        if ($version !== 0 && (!isset($versions[$version]) || !isset($migrations[$version]))) {
             $io->out(sprintf(
                 '<comment>warning</comment> %s is not a valid version',
                 $version,
@@ -1304,12 +1304,12 @@ protected function markBreakpoint(?int $version, int $mark): void
                 $env->getAdapter()->toggleBreakpoint($migrations[$version]);
                 break;
             case self::BREAKPOINT_SET:
-                if ($versions[$version]['breakpoint'] == 0) {
+                if ((int)$versions[$version]['breakpoint'] === 0) {
                     $env->getAdapter()->setBreakpoint($migrations[$version]);
                 }
                 break;
             case self::BREAKPOINT_UNSET:
-                if ($versions[$version]['breakpoint'] == 1) {
+                if ((int)$versions[$version]['breakpoint'] === 1) {
                     $env->getAdapter()->unsetBreakpoint($migrations[$version]);
                 }
                 break;

src/Util/ColumnParser.php

@@ -74,7 +74,7 @@ public function parseFields(array $arguments): array
                 $type = str_contains($type, '?') ? 'integer?' : 'integer';
             }
 
-            $nullable = (bool)strpos($type, '?');
+            $nullable = str_contains($type, '?');
             $type = $nullable ? str_replace('?', '', $type) : $type;
 
             [$type, $length] = $this->getTypeAndLength($field, $type);