[clang-tools-extra] r325097 - [clangd] Configure clangd tracing with CLANGD_TRACE env instead of -trace flag

[Sam McCall via cfe-commits]

Author: sammccall
Date: Tue Feb 13 19:20:07 2018
New Revision: 325097

URL: http://llvm.org/viewvc/llvm-project?rev=325097&view=rev
Log:
[clangd] Configure clangd tracing with CLANGD_TRACE env instead of -trace flag

Modified:
    clang-tools-extra/trunk/clangd/tool/ClangdMain.cpp
    clang-tools-extra/trunk/test/clangd/trace.test

Modified: clang-tools-extra/trunk/clangd/tool/ClangdMain.cpp
URL: http://llvm.org/viewvc/llvm-project/clang-tools-extra/trunk/clangd/tool/ClangdMain.cpp?rev=325097&r1=325096&r2=325097&view=diff
==============================================================================
--- clang-tools-extra/trunk/clangd/tool/ClangdMain.cpp (original)
+++ clang-tools-extra/trunk/clangd/tool/ClangdMain.cpp Tue Feb 13 19:20:07 2018
@@ -17,6 +17,7 @@
 #include "llvm/Support/Path.h"
 #include "llvm/Support/Program.h"
 #include "llvm/Support/raw_ostream.h"
+#include <cstdlib>
 #include <iostream>
 #include <memory>
 #include <string>
@@ -123,12 +124,6 @@ static llvm::cl::opt<Path> InputMirrorFi
         "Mirror all LSP input to the specified file. Useful for debugging."),
     llvm::cl::init(""), llvm::cl::Hidden);
 
-static llvm::cl::opt<Path> TraceFile(
-    "trace",
-    llvm::cl::desc(
-        "Trace internal events and timestamps in chrome://tracing JSON format"),
-    llvm::cl::init(""), llvm::cl::Hidden);
-
 static llvm::cl::opt<bool> EnableIndexBasedCompletion(
     "enable-index-based-completion",
     llvm::cl::desc(
@@ -176,15 +171,18 @@ int main(int argc, char *argv[]) {
     }
   }
 
-  // Setup tracing facilities.
+  // Setup tracing facilities if CLANGD_TRACE is set. In practice enabling a
+  // trace flag in your editor's config is annoying, launching with
+  // `CLANGD_TRACE=trace.json vim` is easier.
   llvm::Optional<llvm::raw_fd_ostream> TraceStream;
   std::unique_ptr<trace::EventTracer> Tracer;
-  if (!TraceFile.empty()) {
+  if (auto *TraceFile = getenv("CLANGD_TRACE")) {
     std::error_code EC;
     TraceStream.emplace(TraceFile, /*ref*/ EC, llvm::sys::fs::F_RW);
     if (EC) {
-      TraceFile.reset();
-      llvm::errs() << "Error while opening trace file: " << EC.message();
+      TraceStream.reset();
+      llvm::errs() << "Error while opening trace file " << TraceFile << ": "
+                   << EC.message();
     } else {
       Tracer = trace::createJSONTracer(*TraceStream, PrettyPrint);
     }

Modified: clang-tools-extra/trunk/test/clangd/trace.test
URL: http://llvm.org/viewvc/llvm-project/clang-tools-extra/trunk/test/clangd/trace.test?rev=325097&r1=325096&r2=325097&view=diff
==============================================================================
--- clang-tools-extra/trunk/test/clangd/trace.test (original)
+++ clang-tools-extra/trunk/test/clangd/trace.test Tue Feb 13 19:20:07 2018
@@ -1,4 +1,4 @@
-# RUN: clangd -lit-test -trace %t < %s && FileCheck %s < %t
+# RUN: CLANGD_TRACE=%t clangd -lit-test < %s && FileCheck %s < %t
 {"jsonrpc":"2.0","id":0,"method":"initialize","params":{"processId":123,"rootPath":"clangd","capabilities":{},"trace":"off"}}
 ---
 {"jsonrpc":"2.0","method":"textDocument/didOpen","params":{"textDocument":{"uri":"test:///foo.c","languageId":"c","version":1,"text":"void main() {}"}}}