Fix test for `chmod +x` on binaries.

Library/Homebrew/test/cask/artifact/binary_spec.rb

@@ -6,9 +6,7 @@ describe Hbc::Artifact::Binary, :cask do
       end
     end
   }
-  let(:expected_path) {
-    Hbc.binarydir.join("binary")
-  }
+  let(:expected_path) { Hbc.binarydir.join("binary") }
 
   before(:each) do
     Hbc.binarydir.mkpath
@@ -26,15 +24,28 @@ describe Hbc::Artifact::Binary, :cask do
     expect(expected_path.readlink).to exist
   end
 
-  it "makes the binary executable" do
-    expect(FileUtils).to receive(:chmod).with("+x", cask.staged_path.join("binary"))
+  context "when the binary is not executable" do
+    let(:cask) {
+      Hbc::CaskLoader.load_from_file(TEST_FIXTURE_DIR/"cask/Casks/with-non-executable-binary.rb").tap do |cask|
+        shutup do
+          InstallHelper.install_without_artifacts(cask)
+        end
+      end
+    }
 
-    shutup do
-      Hbc::Artifact::Binary.new(cask).install_phase
-    end
+    let(:expected_path) { Hbc.binarydir.join("naked_non_executable") }
 
-    expect(expected_path).to be_a_symlink
-    expect(expected_path.readlink).to be_executable
+    it "makes the binary executable" do
+      expect(FileUtils).to receive(:chmod)
+        .with("+x", cask.staged_path.join("naked_non_executable")).and_call_original
+
+      shutup do
+        Hbc::Artifact::Binary.new(cask).install_phase
+      end
+
+      expect(expected_path).to be_a_symlink
+      expect(expected_path.readlink).to be_executable
+    end
   end
 
   it "avoids clobbering an existing binary by linking over it" do

Library/Homebrew/test/support/fixtures/cask/Casks/with-non-executable-binary.rb

+cask 'with-non-executable-binary' do
+  version '1.2.3'
+  sha256 'd5b2dfbef7ea28c25f7a77cd7fa14d013d82b626db1d82e00e25822464ba19e2'
+
+  url "file://#{TEST_FIXTURE_DIR}/cask/naked_non_executable"
+  homepage 'http://example.com/with-binary'
+
+  binary "naked_non_executable"
+end

Library/Homebrew/test/support/fixtures/cask/naked_non_executable

+#!/bin/sh
+exit 0