fix quadratic scan on scheme-less input that cannot be a host - #116
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fix quadratic scan on scheme-less input that cannot be a host#116hey-jj wants to merge 1 commit into
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When require_host is set and the current candidate can no longer be a valid host, stop scanning instead of running to the end of the input. Each candidate used to scan to the end, which made link extraction with url_must_have_scheme(false) quadratic on inputs like "a.a~" repeated. Fixes robinst#115
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fixes #115
when
require_hostis set andmaybe_hosthas gone false,find_authority_endkept scanning to the end of the input... every candidate did that, so extraction withurl_must_have_scheme(false)goes quadratic on text likea.a~repeated. the guard breaks out as soon as the position can no longer be part of a valid authority.this is safe because nothing past that point can change the result: once
require_hostis set andmaybe_hostis false, the function returns(None, None)no matter where the scan stops. the ONLY state change that could revive the candidate is@resettingmaybe_host, and that can only happen while userinfo is still allowed, where the guard does not fire.includes a regression test with a large repeated
a.a~input that hangs without the fix and runs in milliseconds with it.