wip

src/Plugins/Tia/TableExtractor.php

@@ -0,0 +1,154 @@
+<?php
+
+declare(strict_types=1);
+
+namespace Pest\Plugins\Tia;
+
+/**
+ * Extracts table names from SQL statements and migration PHP sources.
+ *
+ * Two callers, two methods:
+ *
+ *   - `fromSql()` runs against query strings Laravel's `DB::listen`
+ *     hands us at record time. We only look at DML (`SELECT`, `INSERT`,
+ *     `UPDATE`, `DELETE`) because DDL emitted by `RefreshDatabase` in
+ *     `setUp()` is noise — we don't want every test to end up linked
+ *     to every migration's `CREATE TABLE`.
+ *   - `fromMigrationSource()` reads a migration file on disk at
+ *     replay time and pulls table names out of `Schema::` calls.
+ *     Used in two places:
+ *       1. For every migration file reported as changed — what
+ *          tables does the current version of this file touch?
+ *       2. For brand-new migration files that weren't in the graph
+ *          yet, so we never had a chance to observe their DDL.
+ *
+ * Regex isn't a parser. CTEs, subqueries, and raw `DB::statement()`
+ * that reference tables only inside exotic syntax can slip through.
+ * The direction of that error is under-attribution (a table the test
+ * genuinely touches but we missed), so the safety net is to keep the
+ * broad `database/migrations/**` watch pattern as a last resort for
+ * files that produce an empty extraction.
+ *
+ * @internal
+ */
+final class TableExtractor
+{
+    /**
+     * DML prefixes we accept. DDL (`CREATE`, `ALTER`, `DROP`,
+     * `TRUNCATE`, `RENAME`) is deliberately excluded — those come
+     * from migrations fired by `RefreshDatabase`, and capturing them
+     * here would attribute every migration table to every test.
+     */
+    private const array DML_PREFIXES = ['select', 'insert', 'update', 'delete'];
+
+    /**
+     * @return list<string> Sorted, deduped table names referenced by the
+     *                      SQL statement. Empty when the statement is
+     *                      DDL, empty, or unparseable.
+     */
+    public static function fromSql(string $sql): array
+    {
+        $trimmed = ltrim($sql);
+
+        if ($trimmed === '') {
+            return [];
+        }
+
+        $prefix = strtolower(substr($trimmed, 0, 6));
+
+        $matched = false;
+        foreach (self::DML_PREFIXES as $dml) {
+            if (str_starts_with($prefix, $dml)) {
+                $matched = true;
+
+                break;
+            }
+        }
+
+        if (! $matched) {
+            return [];
+        }
+
+        // Match `from`, `into`, `update`, `join` and capture the
+        // following identifier, tolerating the common quoting
+        // styles: "double", `back`, [bracket], or bare.
+        $pattern = '/(?:\bfrom|\binto|\bupdate|\bjoin)\s+(?:"([^"]+)"|`([^`]+)`|\[([^\]]+)\]|(\w+))/i';
+
+        if (preg_match_all($pattern, $sql, $matches) === false) {
+            return [];
+        }
+
+        $tables = [];
+
+        for ($i = 0, $n = count($matches[0]); $i < $n; $i++) {
+            $name = $matches[1][$i] !== ''
+                ? $matches[1][$i]
+                : ($matches[2][$i] !== ''
+                    ? $matches[2][$i]
+                    : ($matches[3][$i] !== ''
+                        ? $matches[3][$i]
+                        : $matches[4][$i]));
+            if ($name === '') {
+                continue;
+            }
+            if (self::isSchemaMeta($name)) {
+                continue;
+            }
+
+            $tables[strtolower($name)] = true;
+        }
+
+        $out = array_keys($tables);
+        sort($out);
+
+        return $out;
+    }
+
+    /**
+     * @return list<string> Table names referenced by `Schema::` calls
+     *                      in the given migration file contents. Empty
+     *                      when nothing matches — callers treat that
+     *                      as "fall back to the broad watch pattern".
+     */
+    public static function fromMigrationSource(string $php): array
+    {
+        $pattern = '/Schema::\s*(?:create|table|drop|dropIfExists|dropColumns|rename)\s*\(\s*[\'"]([^\'"]+)[\'"](?:\s*,\s*[\'"]([^\'"]+)[\'"])?/';
+
+        if (preg_match_all($pattern, $php, $matches) === false) {
+            return [];
+        }
+
+        $tables = [];
+
+        foreach ($matches[1] as $i => $primary) {
+            // Group 1 always captures at least one char per the regex.
+            $tables[strtolower($primary)] = true;
+
+            // Group 2 (`Schema::rename('old', 'new')`) is optional and
+            // absent from non-rename matches.
+            $secondary = $matches[2][$i] ?? '';
+            if ($secondary !== '') {
+                $tables[strtolower($secondary)] = true;
+            }
+        }
+
+        $out = array_keys($tables);
+        sort($out);
+
+        return $out;
+    }
+
+    /**
+     * Filters out driver-internal tables that show up as DB::listen
+     * targets without representing user schema: SQLite's master
+     * catalogue, Laravel's own `migrations` metadata.
+     */
+    private static function isSchemaMeta(string $name): bool
+    {
+        $lower = strtolower($name);
+
+        return in_array($lower, ['sqlite_master', 'sqlite_sequence', 'migrations'], true)
+            || str_starts_with($lower, 'pg_')
+            || str_starts_with($lower, 'information_schema');
+    }
+}