Fix string accessor type mismatch

[dduan]

Summary

• Throw a TOML type mismatch when string access sees a non-string token instead of letting the parser trap.
• Add regression coverage for inline table string accessor mismatch.

Validation

• Not run in this split branch per instruction; this commit was already verified before PR splitting.

[github-actions]

�[33mWarning: running with the Swift runtime interposer on Linux to avoid the Swift 6.3 runtime hook crash. See https://github.com/ordo-one/benchmark/issues/349�[0m

Comparing results between 'main' and 'pull_request'

Host 'runnervm5mmn9' with 4 'x86_64' processors with 15 GB memory, running:
#18~24.04.1-Ubuntu SMP Thu May 28 16:39:11 UTC 2026

TOMLDecoderBenchmarks

Decode toml.io example metrics

Time (wall clock): results within specified thresholds, fold down for details.

Time (wall clock) (μs) *	p0	p25	p50	p75	p90	p99	p100	Samples
main	68	70	70	70	72	86	120	8761
pull_request	67	69	69	69	70	79	147	8817
Δ	-1	-1	-1	-1	-2	-7	27	56
Improvement %	1	1	1	1	3	8	-22	56

Retains: results within specified thresholds, fold down for details.

Retains *	p0	p25	p50	p75	p90	p99	p100	Samples
main	765	765	765	765	765	765	765	8761
pull_request	765	765	765	765	765	765	765	8817
Δ	0	0	0	0	0	0	0	56
Improvement %	0	0	0	0	0	0	0	56

Parse toml.io example metrics

Time (wall clock): results within specified thresholds, fold down for details.

Time (wall clock) (ns) *	p0	p25	p50	p75	p90	p99	p100	Samples
main	4672	4755	4783	4815	4851	5191	38103	10000
pull_request	4711	4823	4847	4875	4907	5291	30667	10000
Δ	39	68	64	60	56	100	-7436	0
Improvement %	-1	-1	-1	-1	-1	-2	20	0

Retains: results within specified thresholds, fold down for details.

Retains *	p0	p25	p50	p75	p90	p99	p100	Samples
main	31	31	31	31	31	31	31	10000
pull_request	31	31	31	31	31	31	31	10000
Δ	0	0	0	0	0	0	0	0
Improvement %	0	0	0	0	0	0	0	0

decode canada.toml metrics

Time (wall clock): results within specified thresholds, fold down for details.

Time (wall clock) (ms) *	p0	p25	p50	p75	p90	p99	p100	Samples
main	269	269	271	272	275	275	275	4
pull_request	267	268	269	270	271	271	271	4
Δ	-2	-1	-2	-2	-4	-4	-4	0
Improvement %	1	0	1	1	1	1	1	0

Retains: results within specified thresholds, fold down for details.

Retains (K) *	p0	p25	p50	p75	p90	p99	p100	Samples
main	1286	1286	1286	1286	1286	1286	1286	4
pull_request	1286	1286	1286	1286	1286	1286	1286	4
Δ	0	0	0	0	0	0	0	0
Improvement %	0	0	0	0	0	0	0	0

decode twitter.toml metrics

Time (wall clock): results within specified thresholds, fold down for details.

Time (wall clock) (ms) *	p0	p25	p50	p75	p90	p99	p100	Samples
main	10	10	10	11	11	12	12	95
pull_request	10	10	10	10	10	11	11	97
Δ	0	0	0	-1	-1	-1	-1	2
Improvement %	0	0	0	9	9	8	8	2

Retains: results within specified thresholds, fold down for details.

Retains (K) *	p0	p25	p50	p75	p90	p99	p100	Samples
main	113	113	113	113	113	113	113	95
pull_request	113	113	113	113	113	113	113	97
Δ	0	0	0	0	0	0	0	2
Improvement %	0	0	0	0	0	0	0	2

parse GitHub events archive metrics

Time (wall clock): results within specified thresholds, fold down for details.

Time (wall clock) (ms) *	p0	p25	p50	p75	p90	p99	p100	Samples
main	139	140	141	148	149	149	149	7
pull_request	139	139	139	143	148	148	148	8
Δ	0	-1	-2	-5	-1	-1	-1	1
Improvement %	0	1	1	3	1	1	1	1

Retains: results within specified thresholds, fold down for details.

Retains (K) *	p0	p25	p50	p75	p90	p99	p100	Samples
main	394	394	394	394	394	394	394	7
pull_request	394	394	394	394	394	394	394	8
Δ	0	0	0	0	0	0	0	1
Improvement %	0	0	0	0	0	0	0	1

parse canada.toml metrics

Time (wall clock): results within specified thresholds, fold down for details.

Time (wall clock) (ms) *	p0	p25	p50	p75	p90	p99	p100	Samples
main	18	18	18	19	19	24	24	54
pull_request	17	18	19	19	19	23	23	54
Δ	-1	0	1	0	0	-1	-1	0
Improvement %	6	0	-6	0	0	4	4	0

Retains: results within specified thresholds, fold down for details.

Retains *	p0	p25	p50	p75	p90	p99	p100	Samples
main	47	47	47	47	47	47	47	54
pull_request	47	47	47	47	47	47	47	54
Δ	0	0	0	0	0	0	0	0
Improvement %	0	0	0	0	0	0	0	0

parse twitter.toml metrics

Time (wall clock): results within specified thresholds, fold down for details.

Time (wall clock) (μs) *	p0	p25	p50	p75	p90	p99	p100	Samples
main	2221	2238	2245	2253	2265	2337	3103	436
pull_request	2214	2228	2232	2241	2263	2613	3078	437
Δ	-7	-10	-13	-12	-2	276	-25	1
Improvement %	0	0	1	1	0	-12	1	1

Retains: results within specified thresholds, fold down for details.

Retains *	p0	p25	p50	p75	p90	p99	p100	Samples
main	7736	7736	7736	7736	7736	7736	7736	436
pull_request	7736	7736	7736	7736	7736	7736	7736	437
Δ	0	0	0	0	0	0	0	1
Improvement %	0	0	0	0	0	0	0	1