[CentOS] How to test for '.' in a script

I am trying to check for a single period '.' in a shell variable.

$ I=.
$ echo $I
.
$ if [[ "$I" -eq '.' ]]; then echo true; fi
-bash: [[: .: syntax error: operand expected (error token is ".")

All other variants of this construct, with and without escape
characters, single and double quote combinations, that I can think
of all give exactly the same error.

How does one check to see for this in a bash script?


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