[joelhawksley]

Reuse source-file reads during digest hashing and avoid per-node AST allocations.

Benchmark	Time ratio change	Allocations (base → head)
Cold digest	-5.7%	76,627 → 73,755 (-3.7%)
Boot	-1.9%	1,374,557 → 1,333,315 (-3.0%)

Three paired 15-pass runs on Ruby 4.1-dev / Rails 8.1.4, with unchanged workloads. Rendering scenarios measured 0.5–1.6% slower, with unchanged allocations.

Benchmark commands

Compare against 5e1e82a2. Repeat the measurement pair three times, using separate output files and reversing the order in the second round.

git worktree add tmp/base 5e1e82a2
PASSES=15 VIEW_COMPONENT_LIB=tmp/base/lib bundle exec ruby performance/measure.rb tmp/performance/base/1.json
PASSES=15 bundle exec ruby performance/measure.rb tmp/performance/head/1.json
bundle exec ruby performance/compare.rb tmp/performance/base tmp/performance/head

Time ratios compare component digests against partial digests, and ViewComponent boot time against the rest of boot. Lower is better.