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To: 9front@9front.org
Subject: Re: [9front] Patch to fix test(1) expression parsing
Date: Sat, 01 Aug 2020 21:35:11 -0700
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> Hi all,
> 
> The following patch fixes test(1) to correctly parse its own
> expression syntax whilst avoiding executing of filesystem operations
> when these tests ought not to be performed due to short-circuiting.
> 
> Previously, short-circuiting of -a and -o logical operators would
> result in an incorrect parse.  For example, the following invocations

Generally looks good, will test tomorrow -- just a minor comment:

> fail:
> 
> term% test '(' 1 -gt 2 -a 1 -gt 1 ')'
> test: ) expected
> term% test '(' 2 -gt 1 -o 1 -gt 1 ')'
> test: ) expected
> 

> -	r = e();
> +	r = e(1);
>  	/*
>  	 * nice idea but short-circuit -o and -a operators may have
>  	 * not consumed their right-hand sides.

This comment seems outdated -- we can use the nice idea and
error out appropriately now.