From 2f3f017a6ee79dd7e0443f13951f4f54ae81e715 Mon Sep 17 00:00:00 2001
From: Michael Cho <michael@michaelcho.dev>
Date: Thu, 21 Dec 2023 14:05:29 -0500
Subject: [PATCH] rubocops/uses_from_macos: audit when `depends_on :linux`

---
 Library/Homebrew/rubocops/uses_from_macos.rb  |  5 ++
 .../test/rubocops/uses_from_macos_spec.rb     | 49 +++++++++++++++----
 2 files changed, 45 insertions(+), 9 deletions(-)

diff --git a/Library/Homebrew/rubocops/uses_from_macos.rb b/Library/Homebrew/rubocops/uses_from_macos.rb
index 33445382d4..d2efc9fe1e 100644
--- a/Library/Homebrew/rubocops/uses_from_macos.rb
+++ b/Library/Homebrew/rubocops/uses_from_macos.rb
@@ -98,7 +98,12 @@ module RuboCop
         def audit_formula(_node, _class_node, _parent_class_node, body_node)
           return if body_node.nil?
 
+          depends_on_linux = depends_on?(:linux)
+
           find_method_with_args(body_node, :uses_from_macos, /^"(.+)"/).each do |method|
+            @offensive_node = method
+            problem "`uses_from_macos` should not be used when Linux is required." if depends_on_linux
+
             dep = if parameters(method).first.instance_of?(RuboCop::AST::StrNode)
               parameters(method).first
             elsif parameters(method).first.instance_of?(RuboCop::AST::HashNode)
diff --git a/Library/Homebrew/test/rubocops/uses_from_macos_spec.rb b/Library/Homebrew/test/rubocops/uses_from_macos_spec.rb
index b4177bc781..626ff1e64c 100644
--- a/Library/Homebrew/test/rubocops/uses_from_macos_spec.rb
+++ b/Library/Homebrew/test/rubocops/uses_from_macos_spec.rb
@@ -5,16 +5,47 @@ require "rubocops/uses_from_macos"
 describe RuboCop::Cop::FormulaAudit::UsesFromMacos do
   subject(:cop) { described_class.new }
 
-  it "when auditing uses_from_macos dependencies" do
-    expect_offense(<<~RUBY)
-      class Foo < Formula
-        url "https://brew.sh/foo-1.0.tgz"
-        homepage "https://brew.sh"
+  context "when auditing `uses_from_macos` dependencies" do
+    it "reports an offense when used on non-macOS dependency" do
+      expect_offense(<<~RUBY)
+        class Foo < Formula
+          url "https://brew.sh/foo-1.0.tgz"
+          homepage "https://brew.sh"
 
-        uses_from_macos "postgresql"
-        ^^^^^^^^^^^^^^^^^^^^^^^^^^^^ FormulaAudit/UsesFromMacos: `uses_from_macos` should only be used for macOS dependencies, not postgresql.
-      end
-    RUBY
+          uses_from_macos "postgresql"
+          ^^^^^^^^^^^^^^^^^^^^^^^^^^^^ FormulaAudit/UsesFromMacos: `uses_from_macos` should only be used for macOS dependencies, not postgresql.
+        end
+      RUBY
+    end
+
+    it "reports offenses for multiple non-macOS dependencies and none for valid macOS dependencies" do
+      expect_offense(<<~RUBY)
+        class Foo < Formula
+          url "https://brew.sh/foo-1.0.tgz"
+          homepage "https://brew.sh"
+
+          uses_from_macos "boost"
+          ^^^^^^^^^^^^^^^^^^^^^^^ FormulaAudit/UsesFromMacos: `uses_from_macos` should only be used for macOS dependencies, not boost.
+          uses_from_macos "bzip2"
+          uses_from_macos "postgresql"
+          ^^^^^^^^^^^^^^^^^^^^^^^^^^^^ FormulaAudit/UsesFromMacos: `uses_from_macos` should only be used for macOS dependencies, not postgresql.
+          uses_from_macos "zlib"
+        end
+      RUBY
+    end
+
+    it "reports an offense when used in `depends_on :linux` formula" do
+      expect_offense(<<~RUBY)
+        class Foo < Formula
+          url "https://brew.sh/foo-1.0.tgz"
+          homepage "https://brew.sh"
+
+          depends_on :linux
+          uses_from_macos "zlib"
+          ^^^^^^^^^^^^^^^^^^^^^^ FormulaAudit/UsesFromMacos: `uses_from_macos` should not be used when Linux is required.
+        end
+      RUBY
+    end
   end
 
   include_examples "formulae exist", described_class::ALLOWED_USES_FROM_MACOS_DEPS