[clang-tools-extra] [clangd] Add dynamic plugins support (PR #226995)

[Aleksandr Platonov via cfe-commits]

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@@ -0,0 +1,14 @@
+// REQUIRES: plugins
+// RUN: clangd --help | FileCheck --check-prefix=CHECK-HELP %s
+// CHECK-HELP: --load=<pluginfilename> - Load the specified plugin
+
+// RUN: cp %s %t.cpp
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ArcsinX wrote:

I guess here we can't hardcode paths here, because `%s` and `%t` are absolute paths, but we can hardcode only relative and we can't be sure what will be the current working directory at running this test.

https://github.com/llvm/llvm-project/pull/226995