Merge pull request #11134 from Bo98/ignorable-formulary

Introduce Ignorable module and provide the facility to try and ignore errors when loading historical formulae

Library/Homebrew/debrew.rb

@@ -3,10 +3,7 @@
 
 require "mutex_m"
 require "debrew/irb"
-require "warnings"
+require "ignorable"
-Warnings.ignore(/warning: callcc is obsolete; use Fiber instead/) do
-  require "continuation"
-end
 
 # Helper module for debugging formulae.
 #
@@ -14,31 +11,6 @@ end
 module Debrew
   extend Mutex_m
 
-  # Marks exceptions which can be ignored and provides
-  # the ability to jump back to where it was raised.
-  module Ignorable
-    attr_accessor :continuation
-
-    def ignore
-      continuation.call
-    end
-  end
-
-  # Module for allowing to ignore exceptions.
-  module Raise
-    def raise(*)
-      callcc do |continuation|
-        super
-      rescue Exception => e # rubocop:disable Lint/RescueException
-        e.extend(Ignorable)
-        e.continuation = continuation
-        super(e)
-      end
-    end
-
-    alias fail raise
-  end
-
   # Module for allowing to debug formulae.
   module Formula
     def install
@@ -106,28 +78,28 @@ module Debrew
 
   class << self
     extend Predicable
-    alias original_raise raise
     attr_predicate :active?
     attr_reader :debugged_exceptions
   end
 
   def self.debrew
     @active = true
-    Object.include Raise
+    Ignorable.hook_raise
 
     begin
       yield
     rescue SystemExit
-      original_raise
+      raise
     rescue Exception => e # rubocop:disable Lint/RescueException
       e.ignore if debug(e) == :ignore # execution jumps back to where the exception was thrown
     ensure
+      Ignorable.unhook_raise
       @active = false
     end
   end
 
   def self.debug(e)
-    original_raise(e) if !active? || !debugged_exceptions.add?(e) || !try_lock
+    raise(e) if !active? || !debugged_exceptions.add?(e) || !try_lock
 
     begin
       puts e.backtrace.first.to_s
@@ -137,15 +109,15 @@ module Debrew
         Menu.choose do |menu|
           menu.prompt = "Choose an action: "
 
-          menu.choice(:raise) { original_raise(e) }
+          menu.choice(:raise) { raise(e) }
-          menu.choice(:ignore) { return :ignore } if e.is_a?(Ignorable)
+          menu.choice(:ignore) { return :ignore } if e.is_a?(Ignorable::ExceptionMixin)
           menu.choice(:backtrace) { puts e.backtrace }
 
-          if e.is_a?(Ignorable)
+          if e.is_a?(Ignorable::ExceptionMixin)
             menu.choice(:irb) do
               puts "When you exit this IRB session, execution will continue."
               set_trace_func proc { |event, _, _, id, binding, klass|
-                if klass == Raise && id == :raise && event == "return"
+                if klass == Object && id == :raise && event == "return"
                   set_trace_func(nil)
                   synchronize { IRB.start_within(binding) }
                 end

Library/Homebrew/debrew/irb.rb

@@ -5,8 +5,6 @@ require "irb"
 
 # @private
 module IRB
-  def self.parse_opts(argv: nil); end
-
   def self.start_within(binding)
     unless @setup_done
       setup(nil, argv: [])
@@ -19,7 +17,7 @@ module IRB
     @CONF[:IRB_RC]&.call(irb.context)
     @CONF[:MAIN_CONTEXT] = irb.context
 
-    trap("SIGINT") do
+    prev_trap = trap("SIGINT") do
       irb.signal_handle
     end
 
@@ -28,6 +26,7 @@ module IRB
         irb.eval_input
       end
     ensure
+      trap("SIGINT", prev_trap)
       irb_at_exit
     end
   end

Library/Homebrew/formula_versions.rb

@@ -45,7 +45,7 @@ class FormulaVersions
 
     yield @formula_at_revision[rev] ||= begin
       contents = file_contents_at_revision(rev)
-      nostdout { Formulary.from_contents(name, path, contents) }
+      nostdout { Formulary.from_contents(name, path, contents, ignore_errors: true) }
     end
   rescue *IGNORED_EXCEPTIONS => e
     # We rescue these so that we can skip bad versions and

Library/Homebrew/formulary.rb

@@ -47,24 +47,35 @@ module Formulary
     super
   end
 
-  def self.load_formula(name, path, contents, namespace, flags:)
+  def self.load_formula(name, path, contents, namespace, flags:, ignore_errors:)
     raise "Formula loading disabled by HOMEBREW_DISABLE_LOAD_FORMULA!" if Homebrew::EnvConfig.disable_load_formula?
 
     require "formula"
+    require "ignorable"
 
     mod = Module.new
     remove_const(namespace) if const_defined?(namespace)
     const_set(namespace, mod)
 
-    begin
+    eval_formula = lambda do
       # Set `BUILD_FLAGS` in the formula's namespace so we can
       # access them from within the formula's class scope.
       mod.const_set(:BUILD_FLAGS, flags)
       mod.module_eval(contents, path)
     rescue NameError, ArgumentError, ScriptError, MethodDeprecatedError, MacOSVersionError => e
+      if e.is_a?(Ignorable::ExceptionMixin)
+        e.ignore
+      else
         remove_const(namespace)
         raise FormulaUnreadableError.new(name, e)
       end
+    end
+    if ignore_errors
+      Ignorable.hook_raise(&eval_formula)
+    else
+      eval_formula.call
+    end
+
     class_name = class_s(name)
 
     begin
@@ -79,10 +90,10 @@ module Formulary
     end
   end
 
-  def self.load_formula_from_path(name, path, flags:)
+  def self.load_formula_from_path(name, path, flags:, ignore_errors:)
     contents = path.open("r") { |f| ensure_utf8_encoding(f).read }
     namespace = "FormulaNamespace#{Digest::MD5.hexdigest(path.to_s)}"
-    klass = load_formula(name, path, contents, namespace, flags: flags)
+    klass = load_formula(name, path, contents, namespace, flags: flags, ignore_errors: ignore_errors)
     cache[path] = klass
   end
 
@@ -150,23 +161,24 @@ module Formulary
     # Gets the formula instance.
     # `alias_path` can be overridden here in case an alias was used to refer to
     # a formula that was loaded in another way.
-    def get_formula(spec, alias_path: nil, force_bottle: false, flags: [])
+    def get_formula(spec, alias_path: nil, force_bottle: false, flags: [], ignore_errors: false)
       alias_path ||= self.alias_path
-      klass(flags: flags).new(name, path, spec, alias_path: alias_path, force_bottle: force_bottle)
+      klass(flags: flags, ignore_errors: ignore_errors)
+        .new(name, path, spec, alias_path: alias_path, force_bottle: force_bottle)
     end
 
-    def klass(flags:)
+    def klass(flags:, ignore_errors:)
-      load_file(flags: flags) unless Formulary.formula_class_defined?(path)
+      load_file(flags: flags, ignore_errors: ignore_errors) unless Formulary.formula_class_defined?(path)
       Formulary.formula_class_get(path)
     end
 
     private
 
-    def load_file(flags:)
+    def load_file(flags:, ignore_errors:)
       $stderr.puts "#{$PROGRAM_NAME} (#{self.class.name}): loading #{path}" if debug?
       raise FormulaUnavailableError, name unless path.file?
 
-      Formulary.load_formula_from_path(name, path, flags: flags)
+      Formulary.load_formula_from_path(name, path, flags: flags, ignore_errors: ignore_errors)
     end
   end
 
@@ -191,10 +203,11 @@ module Formulary
       super name, Formulary.path(full_name)
     end
 
-    def get_formula(spec, force_bottle: false, flags: [], **)
+    def get_formula(spec, force_bottle: false, flags: [], ignore_errors: false, **)
       formula = begin
         contents = Utils::Bottles.formula_contents @bottle_filename, name: name
-        Formulary.from_contents(name, path, contents, spec, force_bottle: force_bottle, flags: flags)
+        Formulary.from_contents(name, path, contents, spec, force_bottle: force_bottle,
+                                flags: flags, ignore_errors: ignore_errors)
       rescue FormulaUnreadableError => e
         opoo <<~EOS
           Unreadable formula in #{@bottle_filename}:
@@ -245,7 +258,7 @@ module Formulary
       super formula, HOMEBREW_CACHE_FORMULA/File.basename(uri.path)
     end
 
-    def load_file(flags:)
+    def load_file(flags:, ignore_errors:)
       if %r{githubusercontent.com/[\w-]+/[\w-]+/[a-f0-9]{40}(?:/Formula)?/(?<formula_name>[\w+-.@]+).rb} =~ url
         raise UsageError, "Installation of #{formula_name} from a GitHub commit URL is unsupported! " \
                   "`brew extract #{formula_name}` to a stable tap on GitHub instead."
@@ -309,7 +322,7 @@ module Formulary
       [name, path]
     end
 
-    def get_formula(spec, alias_path: nil, force_bottle: false, flags: [])
+    def get_formula(spec, alias_path: nil, force_bottle: false, flags: [], ignore_errors: false)
       super
     rescue FormulaUnreadableError => e
       raise TapFormulaUnreadableError.new(tap, name, e.formula_error), "", e.backtrace
@@ -319,7 +332,7 @@ module Formulary
       raise TapFormulaUnavailableError.new(tap, name), "", e.backtrace
     end
 
-    def load_file(flags:)
+    def load_file(flags:, ignore_errors:)
       super
     rescue MethodDeprecatedError => e
       e.issues_url = tap.issues_url || tap.to_s
@@ -348,10 +361,10 @@ module Formulary
       super name, path
     end
 
-    def klass(flags:)
+    def klass(flags:, ignore_errors:)
       $stderr.puts "#{$PROGRAM_NAME} (#{self.class.name}): loading #{path}" if debug?
       namespace = "FormulaNamespace#{Digest::MD5.hexdigest(contents.to_s)}"
-      Formulary.load_formula(name, path, contents, namespace, flags: flags)
+      Formulary.load_formula(name, path, contents, namespace, flags: flags, ignore_errors: ignore_errors)
     end
   end
 
@@ -362,7 +375,10 @@ module Formulary
   # * a formula pathname
   # * a formula URL
   # * a local bottle reference
-  def self.factory(ref, spec = :stable, alias_path: nil, from: nil, force_bottle: false, flags: [])
+  def self.factory(
+    ref, spec = :stable, alias_path: nil, from: nil,
+    force_bottle: false, flags: [], ignore_errors: false
+  )
     raise ArgumentError, "Formulae must have a ref!" unless ref
 
     cache_key = "#{ref}-#{spec}-#{alias_path}-#{from}"
@@ -372,7 +388,8 @@ module Formulary
     end
 
     formula = loader_for(ref, from: from).get_formula(spec, alias_path: alias_path,
-                                                      force_bottle: force_bottle, flags: flags)
+                                                      force_bottle: force_bottle, flags: flags,
+                                                      ignore_errors: ignore_errors)
     if factory_cached?
       cache[:formulary_factory] ||= {}
       cache[:formulary_factory][cache_key] ||= formula
@@ -433,9 +450,13 @@ module Formulary
   end
 
   # Return a {Formula} instance directly from contents.
-  def self.from_contents(name, path, contents, spec = :stable, alias_path: nil, force_bottle: false, flags: [])
+  def self.from_contents(
+    name, path, contents, spec = :stable, alias_path: nil,
+    force_bottle: false, flags: [], ignore_errors: false
+  )
     FormulaContentsLoader.new(name, path, contents)
-                         .get_formula(spec, alias_path: alias_path, force_bottle: force_bottle, flags: flags)
+                         .get_formula(spec, alias_path: alias_path, force_bottle: force_bottle,
+                                      flags: flags, ignore_errors: ignore_errors)
   end
 
   def self.to_rack(ref)

Library/Homebrew/ignorable.rb

@@ -0,0 +1,58 @@
+# typed: false
+# frozen_string_literal: true
+
+require "warnings"
+Warnings.ignore(/warning: callcc is obsolete; use Fiber instead/) do
+  require "continuation"
+end
+
+# Provides the ability to optionally ignore errors raised and continue execution.
+#
+# @api private
+module Ignorable
+  # Marks exceptions which can be ignored and provides
+  # the ability to jump back to where it was raised.
+  module ExceptionMixin
+    attr_accessor :continuation
+
+    def ignore
+      continuation.call
+    end
+  end
+
+  def self.hook_raise
+    Object.class_eval do
+      alias_method :original_raise, :raise
+
+      def raise(*)
+        callcc do |continuation|
+          super
+        rescue Exception => e # rubocop:disable Lint/RescueException
+          unless e.is_a?(ScriptError)
+            e.extend(ExceptionMixin)
+            e.continuation = continuation
+          end
+          super(e)
+        end
+      end
+
+      alias_method :fail, :raise
+    end
+
+    return unless block_given?
+
+    yield
+    unhook_raise
+  end
+
+  def self.unhook_raise
+    Object.class_eval do
+      # False positive - https://github.com/rubocop/rubocop/issues/5022
+      # rubocop:disable Lint/DuplicateMethods
+      alias_method :raise, :original_raise
+      alias_method :fail, :original_raise
+      # rubocop:enable Lint/DuplicateMethods
+      undef :original_raise
+    end
+  end
+end