Length of Longest Non-Repeating Substring Your task is to take as input a single string (or list of characters, list of code points, etc.) and return the length of the longest substring with no character appearing more than once.
Aside: This challenge is similar to Longest Non-Repeating Substring, but without the source restriction ranking submissions by their own longest non-repeating substring.

Assumptions

You may assume that the input contains only lowercase letters and is non-empty (ie. the input will match the regex (a-z)+).

This challenge will use the following definition for substring: &quot;A contiguous sequence of characters contained in the input string&quot;

By &quot;non-repeating&quot; I mean that no letter of the substring is repeated more than once


Examples
If the input is abcdefgabc then the longest substrings with no repeating characters are abcdefg and bcdefga (their positions in the string are [abcdefg]abc and a[bcdefga]bc). The length of these substrings is 7, so the output would be 7.
If the input is abadac then the longest substrings with no repeating characters are bad (a[bad]ac) and dac (aba[dac]) so the output is 3.
If the input is aaaaaa then the longest substring with no repeating characters is a so the output is 1.
If the input is abecdeababcabaa then the longest substrings with no repeating characters are abecd ([abecd]eababcabaa)
and cdeab (abe[cdeab]abcabaa). The output is thus 5.
Test Cases
abcdefgabc -&gt; 7
aaaaaa -&gt; 1
abecdeababcabaa -&gt; 5
abadac -&gt; 3
abababab -&gt; 2
helloworld -&gt; 5
longest -&gt; 7
nonrepeating -&gt; 7
substring -&gt; 8
herring -&gt; 4
abracadabra -&gt; 4
codegolf -&gt; 6
abczyoxpicdabcde -&gt; 10

Scoring
This is code-golf. Shortest answer in bytes for each language wins
Jelly, 6 bytes
ẆQƑƇṪL

A monadic link accepting a list of characters (or whatever), which yields the length.
Try it online!
How?
ẆQƑƇṪL - Link: list
Ẇ      - all sublists (ordered by length)
   Ƈ   - filter keep those which are:
  Ƒ    -   invariant under:
 Q     -     deduplication
    Ṫ  - tail
     L - length