fix: unbounded regex quantifiers prevent Outlines DFA state explosion#203
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The outlines v1.2 API requires: 1. Wrapping the HF model+tokenizer in outlines.Transformers 2. Calling get_regex_logits_processor(None, wrapped, regex) Prior code tried to construct OutlinesLogitsProcessor directly with a tokenizer= kwarg that doesn't exist in v1.2. The error was caught and silently fell back to unconstrained generation. Tests now verify the ACTUAL API surface (import paths + factory function signature) instead of just checking class names exist. This would have caught all three prior Outlines bugs: - PR #197: wrong class name (RegexLogitsProcessor) - PR #201: wrong constructor (tokenizer= kwarg) - This PR: wrong API pattern (direct constructor vs factory) 33/33 tests pass with outlines 1.2.12 installed. Co-Authored-By: Claude Opus 4.6 (1M context) <noreply@anthropic.com>
Bounded quantifiers like {1,500} create counting DFA states that
cross-product with every alternative in the regex. The Thought
prefix alone created 1,500 states, exceeding Outlines' 2^31 limit.
Changes:
- [^\n]{1,500} → [^\n]+ (Thought prefix: 1 state vs 1,500)
- [^"]{0,200} → [^"]* (TYPE text: 1 state vs 200)
- \d{1,3} → \d+ (coordinates: 1 state vs 3)
max_new_tokens=512 provides the actual length limit. The DFA
doesn't need to count characters.
New test: test_no_bounded_quantifiers_in_regex asserts no quantifier
in the regex exceeds {N,10}, preventing future regressions.
34/34 tests pass.
Co-Authored-By: Claude Opus 4.6 (1M context) <noreply@anthropic.com>
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Summary
Bounded quantifiers (
{1,500},{0,200}) in the constrained decoding regex created counting DFA states that exceeded Outlines' 2^31 state limit. Replaced with unbounded+/*(single-state self-loops).max_new_tokensprovides the actual length limit.Error before:
Failed to build DFA number of DFA states exceeds limit of 2147483647Changes
[^\n]{1,500}[^\n]+[^"]{0,200}[^"]*\d{1,3}\d+New regression test:
test_no_bounded_quantifiers_in_regexasserts no quantifier exceeds{N,10}.Test plan
🤖 Generated with Claude Code