Merge pull request #2077 from hzeller/20240125-read-projectroot-env-var

Provide a way to override the project root the language server uses.

verilog/tools/ls/README.md

@@ -47,14 +47,24 @@ find . -name "*.sv" -o -name "*.svh" -o -name "*.v" | sort > verible.filelist
 ```
 
 The paths in the `verible.filelist` can be either relative to the location of the file or absolute.
-The Language Server looks for the `verible.filelist` file in the workspace directory - a directory delivered by the editor.
+It is possible to change the default name of the filelist with the `--file_list_path <new-file-name>` flag.
+
+### Project Root
+The Language Server looks for the `verible.filelist` file in the project root.
+
+#### From Editor
+The project root is typically determined by the editor and sent to the language server.
 The provided workspace directory can vary between editors, usually it is a directory:
 
-* the editor was started,
-* the editor found the root of the project (e.g. based on `.git` directory)
-* provided by the user in the project's settings.
+* Where the editor was started,
+* Where the editor found the root of the project (e.g. based on `.git` directory)
+* That is provided by the user in the project's settings in the editor.
+
+#### Fallback
+If there is no valid project root directory provided by the editor, Verible falls back to use the current directory.
 
-It is possible to change the default name of the file - it can be done with `--file_list_path <new-file-name>` flag.
+You can override the project root that is used with the environment variable `VERIBLE_LS_PROJECTROOT_OVERRIDE`.
+If that is set, it takes precedence over the editor-provided project root.
 
 ### Adding project-specific linter configuration
 

verilog/tools/ls/verilog-language-server.cc

@@ -185,7 +185,9 @@ void VerilogLanguageServer::PrintStatistics() const {
 verible::lsp::InitializeResult VerilogLanguageServer::InitializeRequestHandler(
     const verible::lsp::InitializeParams &p) {
   // set VerilogProject for the symbol table, if possible
-  if (!p.rootUri.empty()) {
+  if (const char *override_path = getenv("VERIBLE_LS_PROJECTROOT_OVERRIDE")) {
+    ConfigureProject(override_path);
+  } else if (!p.rootUri.empty()) {
     std::string path = verible::lsp::LSPUriToPath(p.rootUri);
     if (path.empty()) {
       LOG(ERROR) << "Unsupported rootUri in initialize request:  " << p.rootUri
@@ -204,6 +206,7 @@ verible::lsp::InitializeResult VerilogLanguageServer::InitializeRequestHandler(
 }
 
 void VerilogLanguageServer::ConfigureProject(absl::string_view project_root) {
+  LOG(INFO) << "Initializing with project-root '" << project_root << "'";
   std::string proj_root = {project_root.begin(), project_root.end()};
   if (proj_root.empty()) {
     proj_root = std::string(verible::file::Dirname(FindFileList(".")));