[Pg-kit] collect enums from table columns when not directly exported

[lukpod1]

Problem

When enums are defined in a separate file (e.g. enums.ts) and imported into schema.ts only for use in table columns — without being re-exported — prepareFromExports never sees them.

generatePgSnapshot then receives enums = [], so pushing to a clean database emits the CREATE TABLE statements that reference the types but skips the CREATE TYPE statements entirely, producing:

PostgresError: type "my_enum" does not exist

This is a common pattern: splitting schema definitions across multiple files is encouraged in the drizzle docs, and there is no obvious reason a user would know they must re-export every enum that a table column references.

Root cause

prepareFromExports only scans Object.values(exports). Enums that are imported transitively (used in columns but not re-exported) are never present in that object.

Fix

After collecting tables, walk each table's columns via getTableColumns (already imported). If a column carries a .enum property that satisfies isPgEnum (already imported) and the enum hasn't been collected yet, add it to the list.

for (const table of tables) {
  for (const column of Object.values(getTableColumns(table))) {
    const enumCol = column as any;
    if (enumCol.enum !== undefined && isPgEnum(enumCol.enum) && !enums.includes(enumCol.enum)) {
      enums.push(enumCol.enum);
    }
  }
}

No new imports or dependencies required.

Tests

Added drizzle-kit/tests/pg-imports.test.ts with two cases:

1. Enum used in column but not exported → must be found
2. Enum both exported and used in column → must not be duplicated