From a8384c0ce77b012738611db206d7c0a2c0261d7d Mon Sep 17 00:00:00 2001
From: apainintheneck <apainintheneck@gmail.com>
Date: Sat, 31 Dec 2022 11:17:17 -0800
Subject: [PATCH] cli/parser: Better error message for cask on linux

1. Validate options before constraint violations. This allows
us to error out when --cask is passed on Linux before getting
a constraint violation when --cask and --formula are set.
2. Skip printing the help page when --cask is passed on Linux.
---
 Library/Homebrew/cli/parser.rb             |  2 +-
 Library/Homebrew/extend/os/linux/parser.rb |  4 ++-
 Library/Homebrew/test/cli/parser_spec.rb   | 33 ++++++++++++++++++----
 3 files changed, 32 insertions(+), 7 deletions(-)

diff --git a/Library/Homebrew/cli/parser.rb b/Library/Homebrew/cli/parser.rb
index 897d56449d..f2d58d1126 100644
--- a/Library/Homebrew/cli/parser.rb
+++ b/Library/Homebrew/cli/parser.rb
@@ -332,8 +332,8 @@ module Homebrew
         set_default_options
 
         unless ignore_invalid_options
-          check_constraint_violations
           validate_options
+          check_constraint_violations
           check_named_args(named_args)
         end
 
diff --git a/Library/Homebrew/extend/os/linux/parser.rb b/Library/Homebrew/extend/os/linux/parser.rb
index 0c55c5862f..0195c1f67b 100644
--- a/Library/Homebrew/extend/os/linux/parser.rb
+++ b/Library/Homebrew/extend/os/linux/parser.rb
@@ -15,7 +15,9 @@ module Homebrew
         return unless @args.respond_to?(:cask?)
         return unless @args.cask?
 
-        raise UsageError, "Casks are not supported on Linux"
+        # NOTE: We don't raise a UsageError here because
+        # we don't want to print the help page.
+        raise "Invalid usage: Casks are not supported on Linux"
       end
     end
   end
diff --git a/Library/Homebrew/test/cli/parser_spec.rb b/Library/Homebrew/test/cli/parser_spec.rb
index b2983a09bb..51ab257815 100644
--- a/Library/Homebrew/test/cli/parser_spec.rb
+++ b/Library/Homebrew/test/cli/parser_spec.rb
@@ -564,14 +564,37 @@ describe Homebrew::CLI::Parser do
   end
 
   describe "--cask on linux", :needs_linux do
-    subject(:parser) do
-      described_class.new do
-        switch "--cask"
+    context "without --formula switch" do
+      subject(:parser) do
+        described_class.new do
+          switch "--cask"
+        end
+      end
+
+      it "throws an error when defined" do
+        expect { parser.parse(["--cask"]) }
+          .to raise_error RuntimeError, "Invalid usage: Casks are not supported on Linux"
       end
     end
 
-    it "throws an error when defined" do
-      expect { parser.parse(["--cask"]) }.to raise_error UsageError, /Casks are not supported on Linux/
+    context "with conflicting --formula switch" do
+      subject(:parser) do
+        described_class.new do
+          switch "--cask"
+          switch "--formula"
+          conflicts "--cask", "--formula"
+        end
+      end
+
+      it "throws an error when --cask defined" do
+        expect { parser.parse(["--cask"]) }
+          .to raise_error RuntimeError, "Invalid usage: Casks are not supported on Linux"
+      end
+
+      it "throws an error when both defined" do
+        expect { parser.parse(["--cask", "--formula"]) }
+          .to raise_error RuntimeError, "Invalid usage: Casks are not supported on Linux"
+      end
     end
   end