Skip fieldless custom types when exporting to SQL Server

[NgoQuocViet2001]

Problem

tablesToSQLServer guards the first-field access with a comparison that can never be true:

}CREATE TYPE [${type.name}] FROM ${
  type.fields.length < 0
    ? ""
    : `${getTypeString(type.fields[0], obj.database, DB.MSSQL, true)}`
};\nGO\n`;

Array.prototype.length is never negative, so the else branch always runs. For a custom type with no fields, type.fields[0] is undefined, and getTypeString's MSSQL branch starts with let type = field.type;.

How it is reached

A new custom type starts out exactly like that — addType() in src/context/TypesContext.jsx creates it with no starter field:

{ id, name: `type_${prev.length}`, fields: [], comment: "" }

So opening the Types tab, adding a type, and choosing Export source → MSSQL before giving it a field is enough. Exporting a generic diagram with that type:

export THREW: TypeError: Cannot read properties of undefined (reading 'type')

In the editor this surfaces as an export that silently produces nothing, since the menu handler calls jsonToSQLServer without a try/catch.

Fix

Drop fieldless types before mapping, and remove the dead ternary the filter replaces. CREATE TYPE ... FROM needs a base type, and a fieldless type has none to offer, so there is nothing valid to emit for it.

Test plan

• Ran jsonToSQLServer (bundled with esbuild, since the module uses extensionless imports) against a generic diagram containing one table, one fieldless type and one type with a DECIMAL field:
  • before: throws the TypeError above
  • after: emits CREATE TYPE [money_t] FROM DECIMAL; for the populated type, skips the empty one, and the table follows unchanged
• Ran: npm run lint → clean.
• There is no test suite in the repo to extend.

[vercel]

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[danielgwilson]

Humanish project operator check (automated): I exercised File → Export SQL → MSSQL on local production builds of ca7ba9a and b5c7099, including the actual Export/download button.

• Empty custom type only: base raises the reported TypeError and leaves Export disabled. Head downloads a .sql file containing two newlines, with no invalid CREATE TYPE statement.
• Empty type + populated DECIMAL type + table: base fails the same way. Head downloads SQL that omits the empty type while retaining the populated alias, table/column comments, both columns, identity/default constraints, primary key and index. I compared the complete 321-byte download with the expected SQL.

Both production builds passed using their committed lockfiles. The requested base/head also differ in the js-yaml lock entry (4.3.2/4.3.1). This checks the browser export path; I did not execute the SQL against SQL Server.

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Project	Deployment	Actions	Updated
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[1ilit]

thank you!