[clangd] Support proximity paths in index fuzzy find.

[sammccall]

clangd/index/Index.h

275

Hmm, the returned results have URIs, not paths.

It seems cleaner that the query params be URIs too.
However then we need a way to know which scheme the index expects.

It could expose this information, or the index could accept a path here and do the conversion itself. This indexes need to be "thick" and deal with the URI infrastructure, but may be the simplest way.

What's your thinking here?

[ioeric]

clangd/index/Index.h

275

However then we need a way to know which scheme the index expects.
It could expose this information, or the index could accept a path here and do the conversion itself. This indexes need to be "thick" and deal with the URI infrastructure, but may be the simplest way.

Yeah, I was thinking the same. Also index symbols can have different schemes, and we might not have enough information to know which scheme is preferable until we see a candidate.

[sammccall]

clangd/index/Index.h

275

OK, SGTM

clangd/CodeComplete.cpp

SymbolSlab queryIndex() {
     // Build the query.
     FuzzyFindRequest Req;
     if (Opts.Limit)
       Req.MaxCandidateCount = Opts.Limit;
     Req.Query = Filter->pattern();
     Req.RestrictForCodeCompletion = true;
     Req.Scopes = getQueryScopes(Recorder->CCContext,
                                 Recorder->CCSema->getSourceManager());
+    Req.ProximityPaths.push_back(FileName);
     log(llvm::formatv("Code complete: fuzzyFind(\"{0}\", scopes=[{1}])",
                       Req.Query,
                       llvm::join(Req.Scopes.begin(), Req.Scopes.end(), ",")));
     // Run the query against the index.
     if (Opts.Index->fuzzyFind(
             Req, [&](const Symbol &Sym) { ResultsBuilder.insert(Sym); }))
       Incomplete = true;
     return std::move(ResultsBuilder).build();

clangd/index/Index.h

struct FuzzyFindRequest {
   ///
   /// The global scope is "", a top level scope is "foo::", etc.
   std::vector<std::string> Scopes;
   /// \brief The number of top candidates to return. The index may choose to
   /// return more than this, e.g. if it doesn't know which candidates are best.
   size_t MaxCandidateCount = UINT_MAX;
   /// If set to true, only symbols for completion support will be considered.
   bool RestrictForCodeCompletion = false;
+  /// Contextually relevant files (e.g. the file we're code-completing in).
+  /// Paths should be absolute.
+  std::vector<std::string> ProximityPaths;
 };
 
 struct LookupRequest {
   llvm::DenseSet<SymbolID> IDs;
 };
 
 /// \brief Interface for symbol indexes that can be used for searching or
 /// matching symbols among a set of symbols based on names or unique IDs.