The JSXExpression union incorrectly includes JSXEmptyExpression

[MageJohn]

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• I have tried restarting my IDE and the issue persists.
• I have updated to the latest version of the packages.
• I have searched for related issues and found none that matched my issue.
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Relevant Package

ast-spec

Playground Link

https://typescript-eslint.io/play/#ts=4.3.5&jsx=true&sourceType=module&showAST=es&code=DwQwfA3gvsD04G4g&eslintrc=N4KABGBEBOCuA2BTAzpAXGYBfEWg&tsconfig=N4KABGBEDGD2C2AHAlgGwKYCcDyiAuysAdgM6QBcYoEEkJemy0eAcgK6qoDCAFutAGsylBm3TgwAXxCSgA

Repro Code

// This parses as a JSXExpressionContainer node whose expression is a JSXEmptyExpression node.
<a>{}</a>;

ESLint Config

No response

tsconfig

No response

Expected Result

I expect that when using the AST_NODE_TYPES.JSXExpression type the AST_NODE_TYPES.JSXEmptyExpression won't be a member of the union.

Actual Result

What I see is that the definition of the union is:

export type JSXExpression =
  | JSXEmptyExpression
  | JSXExpressionContainer
  | JSXSpreadChild;

Additional Info

Code like <a>{}</a> is parsed by typescript as a JsxExpression node who's expression value is undefined. As part of converting the JsxExpression node to an ESLint compatible AST, the typescript-estree package replaces the undefined with a JSXEmptyExpression node (relevant code).

However, in the ast-spec package the JSXEmptyExpression type is a part of the JSXExpression union (defined here). As explained above, this is incorrect as the JSXEmptyExpression node is only created as the child of a JSXExpression.

Versions

package	version
@typescript-eslint/ast-spec	5.48.0
@typescript-eslint/typescript-estree	5.48.0

[bradzacher]

From the looks of our snapshots, yeah I think that JSXEmptyExpression should only be valid as a child. Of JSXExpressionContainer.

I thought there was a case that you could have an empty expression by itself, but I can't seem to find it.