Should the loop expression of a ForStatement be an ExpressionStatement?

[fvictorio]

The loop expression of the for statement gest the type ExpressionStatement added:

solidity-parser-antlr/src/ASTBuilder.js

Lines 690 to 693 in ded9c70

	loopExpression: {
	type: 'ExpressionStatement',
	expression: this.visit(ctx.expression(1))
	},

This is causing issues in prettier-solidity, where is difficult to know if an ExpressionStatement should have a semicolon or not (see prettier-solidity/prettier-plugin-solidity#46 and prettier-solidity/prettier-plugin-solidity#64 for the details). Since the loop expression of a for doesn't have a semicolon, calling it an ExpressionStatement feels wrong.

My question is if there's a good reason to do this, and if there's a chance of modifying it.

Thanks!

[federicobond]

Internally, the reference implementation of Solidity uses an ExpressionStatement, so I would approach this change carefully.

The definition of ExpressionStatement is an expression followed by a semicolon though. If it’s difficult to special case this in prettier then I’m open to accepting a pull request to update the parser. Make sure you include the change in the changelog too.