Add tests

Library/Homebrew/rubocops/cask/on_system_conditionals.rb

@@ -41,7 +41,7 @@ module RuboCop
           end
 
           audit_arch_conditionals(cask_body)
-          audit_macos_version_conditionals(cask_body)
+          audit_macos_version_conditionals(cask_body, recommend_on_system: false)
           simplify_sha256_stanzas
         end
 

Library/Homebrew/rubocops/shared/on_system_conditionals_helper.rb

@@ -91,6 +91,8 @@ module RuboCop
 
         [:arch, :arm?, :intel?].each do |method|
           hardware_cpu_search(body_node, method: method) do |method_node|
+            # These should already be caught by `if_arch_node_search`
+            next if method_node.parent.source.start_with? "if #{method_node.source}"
             next if if_node_is_allowed?(method_node, allowed_methods: allowed_methods, allowed_blocks: allowed_blocks)
 
             offending_node(method_node)
@@ -137,6 +139,8 @@ module RuboCop
           end
 
           macos_version_comparison_search(body_node, os_version: macos_version_option) do |method_node|
+            # These should already be caught by `if_macos_version_node_search`
+            next if method_node.parent.source.start_with? "if #{method_node.source}"
             next if if_node_is_allowed?(method_node, allowed_methods: allowed_methods, allowed_blocks: allowed_blocks)
 
             offending_node(method_node)

Library/Homebrew/test/rubocops/cask/on_system_conditionals_spec.rb

@@ -338,4 +338,105 @@ describe RuboCop::Cop::Cask::OnSystemConditionals do
       include_examples "reports offenses"
     end
   end
+
+  context "when auditing loose `MacOS.version` method calls" do
+    context "when there is a `MacOS.version ==` reference" do
+      let(:source) do
+        <<-CASK.undent
+          cask 'foo' do
+            if MacOS.version == :catalina
+              version "1.0.0"
+            else
+              version "2.0.0"
+            end
+          end
+        CASK
+      end
+      let(:expected_offenses) do
+        [{
+          message:  "Don't use `if MacOS.version == :catalina`, use `on_catalina do` instead.",
+          severity: :convention,
+          line:     2,
+          column:   2,
+          source:   "if MacOS.version == :catalina\n    version \"1.0.0\"\n  else\n    version \"2.0.0\"\n  end",
+        }]
+      end
+
+      include_examples "reports offenses"
+    end
+
+    context "when there is a `MacOS.version <=` reference" do
+      let(:source) do
+        <<-CASK.undent
+          cask 'foo' do
+            if MacOS.version <= :catalina
+              version "1.0.0"
+            else
+              version "2.0.0"
+            end
+          end
+        CASK
+      end
+      let(:expected_offenses) do
+        [{
+          message:  "Don't use `if MacOS.version <= :catalina`, use `on_catalina :or_older do` instead.",
+          severity: :convention,
+          line:     2,
+          column:   2,
+          source:   "if MacOS.version <= :catalina\n    version \"1.0.0\"\n  else\n    version \"2.0.0\"\n  end",
+        }]
+      end
+
+      include_examples "reports offenses"
+    end
+
+    context "when there is a `MacOS.version >=` reference" do
+      let(:source) do
+        <<-CASK.undent
+          cask 'foo' do
+            if MacOS.version >= :catalina
+              version "1.0.0"
+            else
+              version "2.0.0"
+            end
+          end
+        CASK
+      end
+      let(:expected_offenses) do
+        [{
+          message:  "Don't use `if MacOS.version >= :catalina`, use `on_catalina :or_newer do` instead.",
+          severity: :convention,
+          line:     2,
+          column:   2,
+          source:   "if MacOS.version >= :catalina\n    version \"1.0.0\"\n  else\n    version \"2.0.0\"\n  end",
+        }]
+      end
+
+      include_examples "reports offenses"
+    end
+
+    context "when there is a `MacOS.version` reference" do
+      let(:source) do
+        <<-CASK.undent
+          cask 'foo' do
+            version "1.2.3"
+            sha256 "67cdb8a02803ef37fdbf7e0be205863172e41a561ca446cd84f0d7ab35a99d94"
+
+            url "https://example.com/foo-\#{version}-\#{MacOS.version == :monterey}.zip"
+          end
+        CASK
+      end
+      let(:expected_offenses) do
+        [{
+          message:  "Don't use `MacOS.version == :monterey`, use `on_{macos_version}` blocks instead.",
+          severity: :convention,
+          line:     5,
+          column:   44,
+          source:   "MacOS.version == :monterey",
+        }]
+      end
+
+      include_examples "reports offenses"
+    end
+  end
 end

Library/Homebrew/test/support/fixtures/cask/Casks/with-depends-on-macos-failure.rb

@@ -6,7 +6,15 @@ cask "with-depends-on-macos-failure" do
   homepage "https://brew.sh/with-depends-on-macos-failure"
 
   # guarantee a mismatched release
-  depends_on macos: (MacOS.version == :catalina) ? :mojave : :catalina
+  on_mojave :or_older do
+    depends_on macos: :catalina
+  end
+  on_catalina do
+    depends_on macos: :mojave
+  end
+  on_big_sur :or_newer do
+    depends_on macos: :catalina
+  end
 
   app "Caffeine.app"
 end