feat(migrate-ts): derive regex CHECK from validator.regex @pattern (postgres)

Co-Authored-By: Claude Opus 4.8 (1M context) <noreply@anthropic.com>

Author: dmealing

server/typescript/packages/migrate-ts/src/expected-schema.ts

@@ -312,6 +312,16 @@ function validatorCheck(
       if (v.min === undefined) return null;
       return { name: `${tableName}_${col}_length_chk`, expression: `length(${col}) >= ${v.min}` };
     }
+    case VALIDATOR_SUBTYPE_REGEX: {
+      // Postgres-only: SQLite has no native regex operator.
+      if (dialect === "sqlite" || dialect === "d1") return null;
+      const pattern = v.ownAttr(VALIDATOR_ATTR_PATTERN);
+      if (typeof pattern !== "string" || pattern.length === 0) return null;
+      return {
+        name: `${tableName}_${col}_regex_chk`,
+        expression: `${col} ~ '${pattern.replace(/'/g, "''")}'`,
+      };
+    }
     default:
       return null;
   }

server/typescript/packages/migrate-ts/test/validator-check/regex.test.ts

@@ -0,0 +1,43 @@
+// test/validator-check/regex.test.ts
+import { describe, test, expect } from "bun:test";
+import { MetaDataLoader, InMemoryStringSource } from "@metaobjectsdev/metadata";
+import type { MetaData } from "@metaobjectsdev/metadata";
+import { buildExpectedSchema } from "../../src/expected-schema.js";
+import type { Dialect } from "../../src/types.js";
+
+async function load(json: string): Promise<MetaData> {
+  return (await new MetaDataLoader().load([new InMemoryStringSource(json)])).root;
+}
+const ENTITY = (fieldChildren: string) => JSON.stringify({
+  "metadata.root": { children: [{
+    "object.entity": { name: "User", children: [
+      { "field.long": { name: "id" } },
+      ...JSON.parse(fieldChildren),
+      { "source.rdb": { name: "src", "@table": "users" } },
+      { "identity.primary": { name: "pk", "@fields": ["id"], "@generation": "increment" } },
+    ] },
+  }] },
+});
+function checks(root: MetaData, dialect: Dialect) {
+  return buildExpectedSchema(root, { dialect }).tables[0]!.checks;
+}
+
+describe("validator.regex → CHECK", () => {
+  test("postgres: @pattern → ~ check", async () => {
+    const root = await load(ENTITY(`[{"field.string":{"name":"slug","children":[
+      {"validator.regex":{"name":"re","@pattern":"^[a-z]+$"}}]}}]`));
+    const c = checks(root, "postgres").find((x) => x.name === "users_slug_regex_chk");
+    expect(c?.expression).toBe("slug ~ '^[a-z]+$'");
+  });
+  test("single-quote in pattern is escaped", async () => {
+    const root = await load(ENTITY(`[{"field.string":{"name":"q","children":[
+      {"validator.regex":{"name":"re","@pattern":"o'brien"}}]}}]`));
+    const c = checks(root, "postgres").find((x) => x.name === "users_q_regex_chk");
+    expect(c?.expression).toBe("q ~ 'o''brien'");
+  });
+  test("sqlite: regex emits NO check (no native regex)", async () => {
+    const root = await load(ENTITY(`[{"field.string":{"name":"slug","children":[
+      {"validator.regex":{"name":"re","@pattern":"^[a-z]+$"}}]}}]`));
+    expect(checks(root, "sqlite").some((x) => x.name.includes("_regex_chk"))).toBe(false);
+  });
+});