Add test for parsing with ignore_invalid_options.

Library/Homebrew/cli/args.rb

@@ -20,6 +20,7 @@ module Homebrew
         # Can set these because they will be overwritten by freeze_named_args!
         # (whereas other values below will only be overwritten if passed).
         self[:named_args] = argv.reject { |arg| arg.start_with?("-") }
+        self[:remaining] = []
 
         # Set values needed before Parser#parse has been run.
         return unless set_default_args
@@ -32,6 +33,11 @@ module Homebrew
         self[:universal?] = argv.include?("--universal")
       end
 
+      def freeze_remaining_args!(remaining_args)
+        self[:remaining] = remaining_args
+        self[:remaining].freeze
+      end
+
       def freeze_named_args!(named_args)
         # Reset cache values reliant on named_args
         @formulae = nil

Library/Homebrew/cli/parser.rb

@@ -156,9 +156,7 @@ module Homebrew
         @parser.to_s
       end
 
-      def parse(argv = @argv, ignore_invalid_options: false)
+      def parse_remaining(argv, ignore_invalid_options: false)
-        raise "Arguments were already parsed!" if @args_parsed
-
         i = 0
         remaining = []
 
@@ -189,6 +187,14 @@ module Homebrew
           i += 1
         end
 
+        [remaining, non_options]
+      end
+
+      def parse(argv = @argv, ignore_invalid_options: false)
+        raise "Arguments were already parsed!" if @args_parsed
+
+        remaining, non_options = parse_remaining(argv, ignore_invalid_options: ignore_invalid_options)
+
         named_args = if ignore_invalid_options
           []
         else
@@ -198,6 +204,7 @@ module Homebrew
         check_constraint_violations
         check_named_args(named_args)
         @args.freeze_named_args!(named_args)
+        @args.freeze_remaining_args!(non_options.empty? ? remaining : [*remaining, "--", non_options])
         @args.freeze_processed_options!(@processed_options)
 
         @args_parsed = true

Library/Homebrew/test/cli/parser_spec.rb

@@ -15,6 +15,14 @@ describe Homebrew::CLI::Parser do
       allow(Homebrew::EnvConfig).to receive(:pry?).and_return(true)
     end
 
+    context "when `ignore_invalid_options` is true" do
+      it "passes through invalid options" do
+        args = parser.parse(["-v", "named-arg", "--not-a-valid-option"], ignore_invalid_options: true)
+        expect(args.remaining).to eq ["named-arg", "--not-a-valid-option"]
+        expect(args.named_args).to be_empty
+      end
+    end
+
     it "parses short option" do
       args = parser.parse(["-v"])
       expect(args).to be_verbose