jdx/mise · error · RuntimeError

#{context}: missing sha256

Error message

#{context}: missing sha256

What it means

The Ruby brew shim's MiseDownload.fetch refuses to download when the caller passes an empty or blank sha256. Every fetched artifact must have a checksum so the cache is content-addressed and verified; a missing digest means mise cannot guarantee artifact integrity, so fetch raises immediately.

Source

Thrown at src/system/packages/brew/shim.rb:72

def odie(message)
  $stderr.puts "Error: #{message}"
  exit 1
end

class ShimUnsupportedError < StandardError; end

def shim_unsupported!(feature)
  raise ShimUnsupportedError,
        "formula uses `#{feature}`, which mise's source-build shim does not support"
end

module MiseDownload
  module_function

  # download with redirects into the cache, verify, return the path
  def fetch(url, sha256, context)
    raise "#{context}: missing sha256" if sha256.to_s.strip.empty?
    sha256 = sha256.to_s.strip.downcase
    raise "#{context}: malformed sha256" unless sha256.match?(/\A[0-9a-f]{64}\z/)

    MISE_BREW_CACHE.mkpath
    dest = MISE_BREW_CACHE + "#{sha256}--#{File.basename(URI(url).path)}"
    unless dest.file? && Digest::SHA256.file(dest).hexdigest == sha256
      ohai "Downloading #{url}"
      tmp = Pathname.new("#{dest}.incomplete")
      URI.open(url, "rb", redirect: true) do |remote|
        tmp.open("wb") { |f| IO.copy_stream(remote, f) }
      end
      actual = Digest::SHA256.file(tmp).hexdigest
      if actual != sha256
        tmp.unlink
        raise "#{context}: sha256 mismatch (expected #{sha256}, got #{actual})"
      end
      tmp.rename(dest)
    end

View on GitHub (pinned to afd2eddd3a)

Solutions

1. Provide the correct 64-hex-character sha256 for the artifact in the recipe/invocation.
2. Compute it locally: curl -L <url> | sha256sum, then put the digest into the package config.
3. Regenerate the recipe with a template that includes the checksum field.
4. If the artifact upstream doesn't publish a checksum, pin a version that does or vendor the file.

Example fix

// before
MiseDownload.fetch(url, nil, "clang")
// after
MiseDownload.fetch(url, "e3b0c44298fc1c149afbf4c8996fb92427ae41e4649b934ca495991b7852b855", "clang")

# ruby guard before calling fetch
raise "sha256 required" if sha256.nil? || sha256.to_s.strip.empty?
MiseDownload.fetch(url, sha256, context)

begin
  MiseDownload.fetch(url, sha256, context)
rescue RuntimeError => e
  raise unless e.message.include?("missing sha256")
  # fall back or surface a config error
end

When it happens

Trigger: A brew shim package recipe calls cc/cxx-backed fetch with sha256 nil, '', or whitespace only — e.g. a recipe template that failed to substitute the checksum.

Common situations: Hand-written or generated package recipes missing the sha256 field; templating producing empty checksums; upstream metadata lacking the digest.

Understand the failure class

Background: "missing required argument" and "the following required arguments were not provided": what required-argument errors mean and how to fix them — this error's family across 20 libraries.

Related errors

• #{context}: malformed sha256
• #{context}: sha256 mismatch (expected #{sha256}, got #{actua
• {name}: sha256 is {actual}, the packslip says {}
• brew-cask:{}: cask metadata has no sha256
• failed to decompress #{archive}

AI-assisted analysis of jdx/mise@afd2eddd3a (2026-09-09). Data as JSON: /api/errors/0a3724183e25ced8. Report an issue: GitHub.