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

[via cfe-commits]

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@@ -30,6 +30,36 @@ foreach(dep FileCheck count not llvm-config)
   endif()
 endforeach()
 
+if (NOT WIN32 OR NOT LLVM_LINK_LLVM_DYLIB)
+  llvm_add_library(
+      ClangdFeatureModuleExample
+      MODULE FeatureModuleExample.cpp
+      PLUGIN_TOOL clangd
+      PARTIAL_SOURCES_INTENDED)
+  llvm_add_library(
+      ClangdStandaloneTweakExample
+      MODULE StandaloneTweakExample.cpp
+      PLUGIN_TOOL clangd
+      PARTIAL_SOURCES_INTENDED)
+endif()
+
+foreach(target ClangdFeatureModuleExample ClangdStandaloneTweakExample)
+  if(TARGET ${target})
+    list(APPEND CLANGD_TEST_DEPS ${target})
+    target_include_directories(${target} PUBLIC BEFORE
+      "${CLANG_TOOLS_SOURCE_DIR}/clangd"
+      "${CMAKE_CURRENT_BINARY_DIR}/.."
+    )
+    if(CLANG_PLUGIN_SUPPORT AND (WIN32 OR CYGWIN))
+      set(LLVM_LINK_COMPONENTS
+        Support
+      )
+    endif()
+  endif()
+endforeach()
+
+llvm_canonicalize_cmake_booleans(CLANG_PLUGIN_SUPPORT)
----------------
timon-ul wrote:

I am totally fine with keeping it as `CLANG_PLUGIN_SUPPORT`. I wanted to merely bring it up for consideration, but this is not something I consider very important, let's keep it this way then.

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