simplify

Author: chandlerc

toolchain/install/llvm_symlinks_test.py

@@ -38,6 +38,9 @@ def get_link_cmd(self, clang: Path) -> list[str | Path]:
             self.test_o_file,
         ]
 
+    def unsupported(self, stderr: str) -> None:
+        self.fail(f"Unsupported platform '{platform.uname()}':\n{stderr}")
+
     # Note that we can't test `clang` vs. `clang++` portably. The only commands
     # with useful differences are _link_ commands, and those need to build
     # runtime libraries on demand, which requires the host to be able to compile
@@ -47,30 +50,18 @@ def get_link_cmd(self, clang: Path) -> list[str | Path]:
     # test expectations.
     def test_clang(self) -> None:
         bin = self.install_root / "lib/carbon/llvm/bin/clang"
+        # Most errors are caught by ensuring the command succeeds.
         run = subprocess.run(
             self.get_link_cmd(bin), check=True, capture_output=True, text=True
         )
 
-        def unsupported() -> None:
-            self.fail(
-                f"Unsupported platform '{platform.uname()}':\n{run.stderr}"
-            )
-
+        # Also ensure that it correctly didn't imply a C++ link.
         if platform.system() == "Linux":
-            # Check that we do have a plausible link command.
-            if platform.machine() == "x86_64":
-                self.assertRegex(run.stderr, r'"-m" "elf_x86_64"')
-            elif platform.machine() == "AArch64":
-                self.assertRegex(run.stderr, r'"-m" "aarch64linux"')
-            else:
-                unsupported()
-
-            # Ensure it doesn't contain the C++ standard library.
             self.assertNotRegex(run.stderr, r'"-lstdc\+\+"')
         elif platform.system() == "Darwin":
-            unsupported()
+            self.assertNotRegex(run.stderr, r'"-lc\+\+"')
         else:
-            unsupported()
+            self.unsupported(run.stderr)
 
     # Note that we can't test `clang` vs. `clang++` portably. See the comment on
     # `test_clang` for details.
@@ -79,8 +70,14 @@ def test_clangplusplus(self) -> None:
         run = subprocess.run(
             self.get_link_cmd(bin), check=True, capture_output=True, text=True
         )
-        # Ensure it does contain the C++ standard library.
-        self.assertRegex(run.stderr, r'"-lstdc\+\+"')
+
+        # Ensure that this binary _does_ imply a C++ link.
+        if platform.system() == "Linux":
+            self.assertRegex(run.stderr, r'"-lstdc\+\+"')
+        elif platform.system() == "Darwin":
+            self.assertRegex(run.stderr, r'"-lc\+\+"')
+        else:
+            self.unsupported(run.stderr)
 
     def test_clang_cl(self) -> None:
         bin = self.install_root / "lib/carbon/llvm/bin/clang-cl"