[llvm] Add macOS premerge check workflow (PR #207435)

[Aiden Grossman via llvm-commits]

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@@ -78,6 +78,41 @@ def test_llvm_mac(self):
             "",
         )
 
+    def test_mlir_mac(self):
+        env_variables = compute_projects.get_env_variables(
+            ["mlir/CMakeLists.txt"], "Darwin"
+        )
+        self.assertEqual(env_variables["projects_to_build"], "")
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boomanaiden154 wrote:

Here and below, please assert all the variables (to make sure they are actually clear), not just the ones of primary focus.

https://github.com/llvm/llvm-project/pull/207435