Class: Evilution::SourceAstCache

Inherits:
Object
  • Object
show all
Defined in:
lib/evilution/source_ast_cache.rb

Overview

Content-hash-keyed LRU of Prism::ParseResult. Different source bytes always yield a different key, so the cache is valid for the lifetime of the process.

Instance Method Summary collapse

Constructor Details

#initialize(max_entries: DEFAULT_MAX_ENTRIES) ⇒ SourceAstCache

Returns a new instance of SourceAstCache.



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# File 'lib/evilution/source_ast_cache.rb', line 13

def initialize(max_entries: DEFAULT_MAX_ENTRIES)
  @max_entries = max_entries
  @entries = {}
end

Instance Method Details

#fetch(source) ⇒ Object 



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# File 'lib/evilution/source_ast_cache.rb', line 18

def fetch(source)
  return Prism.parse(source) if @max_entries <= 0

  key = Digest::SHA256.digest(source)
  if @entries.key?(key)
    result = @entries.delete(key)
    @entries[key] = result
    return result
  end

  result = Prism.parse(source)
  @entries[key] = result
  evict_until_within_bounds
  result
end