[clang] [clang-tools-extra] [clangd] Retrieve documentation for member function instance from index (PR #153337)

[Thurston Dang via cfe-commits]

thurstond wrote:

CodeCompleteTests.cpp is failing on one of the buildbots (https://lab.llvm.org/buildbot/#/builders/25/builds/12099/steps/11/logs/stdio), which I suspect might be related to this pull request. Could you please take a look?

```
******************** TEST 'Clangd Unit Tests :: ./ClangdTests/26/84' FAILED ********************
Script(shard):
--
GTEST_OUTPUT=json:/home/b/sanitizer-x86_64-linux-bootstrap-ubsan/build/llvm_build_ubsan/tools/clang/tools/extra/clangd/unittests/./ClangdTests-Clangd Unit Tests-931212-26-84.json GTEST_SHUFFLE=0 GTEST_TOTAL_SHARDS=84 GTEST_SHARD_INDEX=26 /home/b/sanitizer-x86_64-linux-bootstrap-ubsan/build/llvm_build_ubsan/tools/clang/tools/extra/clangd/unittests/./ClangdTests
--
Script:
--
/home/b/sanitizer-x86_64-linux-bootstrap-ubsan/build/llvm_build_ubsan/tools/clang/tools/extra/clangd/unittests/./ClangdTests --gtest_filter=CompletionTest.DynamicIndexIncludeInsertion
--
ASTWorker building file /clangd-test/foo_impl.cpp version null with command 
[/clangd-test]
clang -ffreestanding /clangd-test/foo_impl.cpp
Driver produced command: cc1 -cc1 -triple x86_64-unknown-linux-gnu -fsyntax-only -disable-free -clear-ast-before-backend -main-file-name foo_impl.cpp -mrelocation-model pic -pic-level 2 -pic-is-pie -mframe-pointer=all -fmath-errno -ffp-contract=on -fno-rounding-math -mconstructor-aliases -ffreestanding -target-cpu x86-64 -tune-cpu generic -debugger-tuning=gdb -fdebug-compilation-dir=/clangd-test -fcoverage-compilation-dir=/clangd-test -resource-dir lib/clang/22 -internal-isystem lib/clang/22/include -internal-isystem /usr/local/include -internal-externc-isystem /include -internal-externc-isystem /usr/include -fdeprecated-macro -ferror-limit 19 -fgnuc-version=4.2.1 -fskip-odr-check-in-gmf -fcxx-exceptions -fexceptions -no-round-trip-args -faddrsig -D__GCC_HAVE_DWARF2_CFI_ASM=1 -x c++ /clangd-test/foo_impl.cpp
Building first preamble for /clangd-test/foo_impl.cpp version null
Built preamble of size 238484 for file /clangd-test/foo_impl.cpp version null in 5.45 seconds
indexed preamble AST for /clangd-test/foo_impl.cpp version null:
  symbol slab: 2 symbols, 4680 bytes
  ref slab: 0 symbols, 0 refs, 128 bytes
  relations slab: 0 relations, 24 bytes
Build dynamic index for header symbols with estimated memory usage of 7008 bytes
/home/b/sanitizer-x86_64-linux-bootstrap-ubsan/build/llvm-project/clang-tools-extra/clangd/unittests/CodeCompleteTests.cpp:1034: Failure
Value of: Server.blockUntilIdleForTest()
  Actual: false
Expected: true
indexed file AST for /clangd-test/foo_impl.cpp version null:
  symbol slab: 1 symbols, 4448 bytes
  ref slab: 2 symbols, 2 refs, 4272 bytes
  relations slab: 0 relations, 24 bytes
Build dynamic index for main-file symbols with estimated memory usage of 11576 bytes
/home/b/sanitizer-x86_64-linux-bootstrap-ubsan/build/llvm-project/clang-tools-extra/clangd/unittests/CodeCompleteTests.cpp:1034
Value of: Server.blockUntilIdleForTest()
  Actual: false
Expected: true
```


https://github.com/llvm/llvm-project/pull/153337