Benchmarks

EmailBench — competitor comparison harness

A standalone Swift Package that runs SwiftEmailValidator's 243-case DemoApp corpus against a set of other Swift email validation libraries and prints a Markdown-formatted accuracy table.

Kept separate from the main Package.swift so consumers of SwiftEmailValidator don't transitively pull competitor dependencies.

Libraries under test

Key	Library
OursAscii	SwiftEmailValidator — .ascii mode
OursAsciiUnicode	SwiftEmailValidator — .asciiWithUnicodeExtension mode
OursUnicode	SwiftEmailValidator — .unicode mode
EvanRobertsonAscii	evanrobertson/EmailValidator — allowInternational: false
EvanRobertsonInternational	evanrobertson/EmailValidator — allowInternational: true
MimeParser	igorrendulic/MimeEmailParser
Bdolewski	bdolewski/SwiftEmailValidator — regex vendored (their symbol is internal and can't be imported)
JweltonEquivalent	jwelton/EmailValidator — emulated via NSDataDetector to avoid a package-identity collision with evanrobertson's EmailValidator

Deliberately excluded:

• swift-standards/swift-emailaddress-standard — its manifest uses .package(path: "../../swift-ietf/…") and requires macOS 26; it isn't consumable as a Git SPM dependency.
• SwiftValidator / SwiftValidators / adamwaite/Validator — general-purpose form validators, not RFC-focused email parsers.

Running

cd Benchmarks
swift run -c release EmailBench              # print the full report
swift run -c release EmailBench --verbose    # also list every failing case
swift run -c release EmailBench --scope      # within-declared-scope table only
swift run -c release EmailBench --reverse    # run competitor corpora through ours
swift run -c release EmailBench --list       # idx → email mapping (for crash discovery)

Skip list

Some competitors call fatalError on adversarial inputs (out-of-bounds string indexing in their own parsers). Swift's fatalError can't be caught inside the same process, so those inputs are listed in Sources/EmailBench/SkipList.swift and omitted from the library's accuracy denominator. The report surfaces the skip count and the reason in a separate section.

To re-discover crashers (e.g. after adding new corpus cases) use the worker mode:

swift build -c release
for a in OursAscii OursAsciiUnicode OursUnicode \
         EvanRobertsonAscii EvanRobertsonInternational \
         MimeParser Bdolewski JweltonEquivalent; do
  start=0
  while : ; do
    .build/arm64-apple-macosx/release/EmailBench \
      --worker "$a" --start "$start" 2>/dev/null > /tmp/w.log || true
    grep -q '"kind":"done"' /tmp/w.log && break
    crash=$(grep '"kind":"begin"' /tmp/w.log | tail -1 \
              | sed -E 's/.*"idx":([0-9]+).*/\1/')
    echo "$a crashed at idx $crash"
    start=$((crash + 1))
  done
done

Use --list to map indices back to email strings.