[clang-tools-extra] [clangd] [C++20] [Modules] Support code complete for C++20 modules (PR #110083)

[kadir çetinkaya via cfe-commits]

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@@ -402,6 +402,46 @@ import A;
   EXPECT_TRUE(D.isFromASTFile());
 }
 
+// An end to end test for code complete in modules
+TEST_F(PrerequisiteModulesTests, CodeCompleteTest) {
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kadircet wrote:

can you also add a test for signature help?

https://github.com/llvm/llvm-project/pull/110083