[llvm-branch-commits] [libcxx] [libc++][modules] Adds module testing. (PR #76246)

[Louis Dionne via llvm-branch-commits]

================
@@ -131,13 +138,65 @@ def parseScript(test, preamble):
     script += preamble
     script += scriptInTest
 
+    has_std_module = False
+    has_std_compat_module = False
+    for module in modules:
+        if module == "std":
+            has_std_module = True
+        elif module == "std.compat":
+            has_std_compat_module = True
+        else:
+            script.insert(
+                0,
+                f"echo \"The module '{module}' is not valid, use 'std' or 'std.compat'\"",
+            )
+            script.insert(1, "false")
+            return script
+
+    if modules:
+        # This flag is needed for both modules.
+        moduleCompileFlags.append("-fprebuilt-module-path=%T")
+
+        # Building the modules needs to happen before the other script commands
+        # are executed. Therefore the commands are added to the front of the
+        # list.
+        if has_std_compat_module:
+            script.insert(
+                0,
+                "%dbg(MODULE std.compat) %{cxx} %{flags} %{compile_flags} "
+                "-Wno-reserved-module-identifier -Wno-reserved-user-defined-literal "
+                "--precompile -o %T/std.compat.pcm -c %{module}/std.compat.cppm",
----------------
ldionne wrote:

In a follow-up patch, I think we should rename this to `modules-dir`. In fact the other variables might need a renaming too:

```diff
diff --git a/libcxx/test/configs/cmake-bridge.cfg.in b/libcxx/test/configs/cmake-bridge.cfg.in
index 0e3c3040c964..93a7a9bb8129 100644
--- a/libcxx/test/configs/cmake-bridge.cfg.in
+++ b/libcxx/test/configs/cmake-bridge.cfg.in
@@ -25,12 +25,12 @@ config.test_exec_root = os.path.join('@CMAKE_BINARY_DIR@', 'test')
 # Add substitutions for bootstrapping the test suite configuration
 import shlex
 config.substitutions.append(('%{cxx}', shlex.quote('@CMAKE_CXX_COMPILER@')))
-config.substitutions.append(('%{libcxx}', '@LIBCXX_SOURCE_DIR@'))
-config.substitutions.append(('%{include}', '@LIBCXX_GENERATED_INCLUDE_DIR@'))
-config.substitutions.append(('%{target-include}', '@LIBCXX_GENERATED_INCLUDE_TARGET_DIR@'))
-config.substitutions.append(('%{lib}', '@LIBCXX_LIBRARY_DIR@'))
-config.substitutions.append(('%{module}', '@LIBCXX_GENERATED_MODULE_DIR@'))
-config.substitutions.append(('%{test-tools}', '@LIBCXX_TEST_TOOLS_PATH@'))
+config.substitutions.append(('%{libcxx-dir}', '@LIBCXX_SOURCE_DIR@'))
+config.substitutions.append(('%{include-dir}', '@LIBCXX_GENERATED_INCLUDE_DIR@'))
+config.substitutions.append(('%{target-include-dir}', '@LIBCXX_GENERATED_INCLUDE_TARGET_DIR@'))
+config.substitutions.append(('%{lib-dir}', '@LIBCXX_LIBRARY_DIR@'))
+config.substitutions.append(('%{modules-dir}', '@LIBCXX_GENERATED_MODULE_DIR@'))
+config.substitutions.append(('%{test-tools-dir}', '@LIBCXX_TEST_TOOLS_PATH@'))
 
 # The test needs to manually rebuild the module. The compiler flags used in the
 # test need to be the same as the compiler flags used to generate the module.
```

This would make this a lot easier to read IMO.

https://github.com/llvm/llvm-project/pull/76246