Revert "Revert r315214 since diff -Z isn't portable, this is breaking:"

This reverts commit r315242 and restores r315214.

To fix original failure, replaced non-portable `diff -Z` with portable
alternative: `diff -b`.

llvm-svn: 315287

clang-tools-extra/clangd/JSONRPCDispatcher.cpp

@@ -37,6 +37,14 @@ void JSONOutput::log(const Twine &Message) {
   Logs.flush();
 }
 
+void JSONOutput::mirrorInput(const Twine &Message) {
+  if (!InputMirror)
+    return;
+
+  *InputMirror << Message;
+  InputMirror->flush();
+}
+
 void Handler::handleMethod(llvm::yaml::MappingNode *Params, StringRef ID) {
   Output.log("Method ignored.\n");
   // Return that this method is unsupported.
@@ -147,6 +155,14 @@ void clangd::runLanguageServerLoop(std::istream &In, JSONOutput &Out,
         continue;
       }
 
+      Out.mirrorInput(Line);
+      // Mirror '\n' that gets consumed by std::getline, but is not included in
+      // the resulting Line.
+      // Note that '\r' is part of Line, so we don't need to mirror it
+      // separately.
+      if (!In.eof())
+        Out.mirrorInput("\n");
+
       llvm::StringRef LineRef(Line);
 
       // We allow YAML-style comments in headers. Technically this isn't part
@@ -163,9 +179,8 @@ void clangd::runLanguageServerLoop(std::istream &In, JSONOutput &Out,
       if (LineRef.consume_front("Content-Length: ")) {
         if (ContentLength != 0) {
           Out.log("Warning: Duplicate Content-Length header received. "
-                  "The previous value for this message ("
-                  + std::to_string(ContentLength)
-                  + ") was ignored.\n");
+                  "The previous value for this message (" +
+                  std::to_string(ContentLength) + ") was ignored.\n");
         }
 
         llvm::getAsUnsignedInteger(LineRef.trim(), 0, ContentLength);
@@ -185,15 +200,13 @@ void clangd::runLanguageServerLoop(std::istream &In, JSONOutput &Out,
       // parser.
       std::vector<char> JSON(ContentLength + 1, '\0');
       In.read(JSON.data(), ContentLength);
+      Out.mirrorInput(StringRef(JSON.data(), In.gcount()));
 
       // If the stream is aborted before we read ContentLength bytes, In
       // will have eofbit and failbit set.
       if (!In) {
-        Out.log("Input was aborted. Read only "
-                + std::to_string(In.gcount())
-                + " bytes of expected "
-                + std::to_string(ContentLength)
-                + ".\n");
+        Out.log("Input was aborted. Read only " + std::to_string(In.gcount()) +
+                " bytes of expected " + std::to_string(ContentLength) + ".\n");
         break;
       }
 
@@ -209,8 +222,8 @@ void clangd::runLanguageServerLoop(std::istream &In, JSONOutput &Out,
       if (IsDone)
         break;
     } else {
-      Out.log( "Warning: Missing Content-Length header, or message has zero "
-               "length.\n" );
+      Out.log("Warning: Missing Content-Length header, or message has zero "
+              "length.\n");
     }
   }
 }

clang-tools-extra/clangd/JSONRPCDispatcher.h

@@ -24,8 +24,9 @@ namespace clangd {
 /// them.
 class JSONOutput : public Logger {
 public:
-  JSONOutput(llvm::raw_ostream &Outs, llvm::raw_ostream &Logs)
-      : Outs(Outs), Logs(Logs) {}
+  JSONOutput(llvm::raw_ostream &Outs, llvm::raw_ostream &Logs,
+             llvm::raw_ostream *InputMirror = nullptr)
+      : Outs(Outs), Logs(Logs), InputMirror(InputMirror) {}
 
   /// Emit a JSONRPC message.
   void writeMessage(const Twine &Message);
@@ -33,9 +34,15 @@ public:
   /// Write to the logging stream.
   void log(const Twine &Message) override;
 
+  /// Mirror \p Message into InputMirror stream. Does nothing if InputMirror is
+  /// null.
+  /// Unlike other methods of JSONOutput, mirrorInput is not thread-safe.
+  void mirrorInput(const Twine &Message);
+
 private:
   llvm::raw_ostream &Outs;
   llvm::raw_ostream &Logs;
+  llvm::raw_ostream *InputMirror;
 
   std::mutex StreamMutex;
 };

clang-tools-extra/clangd/tool/ClangdMain.cpp

@@ -9,10 +9,12 @@
 
 #include "ClangdLSPServer.h"
 #include "JSONRPCDispatcher.h"
+#include "Path.h"
 #include "llvm/Support/CommandLine.h"
 #include "llvm/Support/FileSystem.h"
 #include "llvm/Support/Path.h"
 #include "llvm/Support/Program.h"
+#include "llvm/Support/raw_ostream.h"
 #include <iostream>
 #include <memory>
 #include <string>
@@ -43,11 +45,17 @@ static llvm::cl::opt<bool> RunSynchronously(
     llvm::cl::desc("Parse on main thread. If set, -j is ignored"),
     llvm::cl::init(false), llvm::cl::Hidden);
 
-static llvm::cl::opt<std::string>
+static llvm::cl::opt<Path>
     ResourceDir("resource-dir",
                 llvm::cl::desc("Directory for system clang headers"),
                 llvm::cl::init(""), llvm::cl::Hidden);
 
+static llvm::cl::opt<Path> InputMirrorFile(
+    "input-mirror-file",
+    llvm::cl::desc(
+        "Mirror all LSP input to the specified file. Useful for debugging."),
+    llvm::cl::init(""), llvm::cl::Hidden);
+
 int main(int argc, char *argv[]) {
   llvm::cl::ParseCommandLineOptions(argc, argv, "clangd");
 
@@ -63,9 +71,21 @@ int main(int argc, char *argv[]) {
     WorkerThreadsCount = 0;
 
   /// Validate command line arguments.
+  llvm::Optional<llvm::raw_fd_ostream> InputMirrorStream;
+  if (!InputMirrorFile.empty()) {
+    std::error_code EC;
+    InputMirrorStream.emplace(InputMirrorFile, /*ref*/ EC, llvm::sys::fs::F_RW);
+    if (EC) {
+      InputMirrorStream.reset();
+      llvm::errs() << "Error while opening an input mirror file: "
+                   << EC.message();
+    }
+  }
+
   llvm::raw_ostream &Outs = llvm::outs();
   llvm::raw_ostream &Logs = llvm::errs();
-  JSONOutput Out(Outs, Logs);
+  JSONOutput Out(Outs, Logs,
+                 InputMirrorStream ? InputMirrorStream.getPointer() : nullptr);
 
   // If --compile-commands-dir arg was invoked, check value and override default
   // path.

clang-tools-extra/test/clangd/input-mirror.test

@@ -0,0 +1,154 @@
+# RUN: clangd -run-synchronously -input-mirror-file %t < %s
+# Note that we have to use '-Z' as -input-mirror-file does not have a newline at the end of file.
+# RUN: diff -b %t %s
+# It is absolutely vital that this file has CRLF line endings.
+#
+Content-Length: 125
+
+{"jsonrpc":"2.0","id":0,"method":"initialize","params":{"processId":123,"rootPath":"clangd","capabilities":{},"trace":"off"}}
+
+Content-Length: 172
+
+{"jsonrpc":"2.0","method":"textDocument/didOpen","params":{"textDocument":{"uri":"file:///main.cpp","languageId":"cpp","version":1,"text":"int main() {\nint a;\na;\n}\n"}}}
+
+Content-Length: 148
+
+{"jsonrpc":"2.0","id":1,"method":"textDocument/definition","params":{"textDocument":{"uri":"file:///main.cpp"},"position":{"line":2,"character":0}}}
+# Go to local variable
+
+Content-Length: 148
+
+{"jsonrpc":"2.0","id":1,"method":"textDocument/definition","params":{"textDocument":{"uri":"file:///main.cpp"},"position":{"line":2,"character":1}}}
+# Go to local variable, end of token
+
+Content-Length: 214
+
+{"jsonrpc":"2.0","method":"textDocument/didChange","params":{"textDocument":{"uri":"file:///main.cpp","version":2},"contentChanges":[{"text":"struct Foo {\nint x;\n};\nint main() {\n  Foo bar = { x : 1 };\n}\n"}]}}
+
+Content-Length: 149
+
+{"jsonrpc":"2.0","id":1,"method":"textDocument/definition","params":{"textDocument":{"uri":"file:///main.cpp"},"position":{"line":4,"character":14}}}
+# Go to field, GNU old-style field designator 
+
+Content-Length: 215
+
+{"jsonrpc":"2.0","method":"textDocument/didChange","params":{"textDocument":{"uri":"file:///main.cpp","version":3},"contentChanges":[{"text":"struct Foo {\nint x;\n};\nint main() {\n  Foo baz = { .x = 2 };\n}\n"}]}}
+
+Content-Length: 149
+
+{"jsonrpc":"2.0","id":1,"method":"textDocument/definition","params":{"textDocument":{"uri":"file:///main.cpp"},"position":{"line":4,"character":15}}}
+# Go to field, field designator 
+
+Content-Length: 187
+
+{"jsonrpc":"2.0","method":"textDocument/didChange","params":{"textDocument":{"uri":"file:///main.cpp","version":4},"contentChanges":[{"text":"int main() {\n   main();\n   return 0;\n}"}]}}
+
+Content-Length: 148
+
+{"jsonrpc":"2.0","id":1,"method":"textDocument/definition","params":{"textDocument":{"uri":"file:///main.cpp"},"position":{"line":1,"character":3}}}
+# Go to function declaration, function call 
+
+Content-Length: 208
+
+{"jsonrpc":"2.0","method":"textDocument/didChange","params":{"textDocument":{"uri":"file:///main.cpp","version":5},"contentChanges":[{"text":"struct Foo {\n};\nint main() {\n   Foo bar;\n   return 0;\n}\n"}]}}
+
+Content-Length: 148
+
+{"jsonrpc":"2.0","id":1,"method":"textDocument/definition","params":{"textDocument":{"uri":"file:///main.cpp"},"position":{"line":3,"character":3}}}
+# Go to struct declaration, new struct instance 
+
+Content-Length: 231
+
+{"jsonrpc":"2.0","method":"textDocument/didChange","params":{"textDocument":{"uri":"file:///main.cpp","version":5},"contentChanges":[{"text":"namespace n1 {\nstruct Foo {\n};\n}\nint main() {\n   n1::Foo bar;\n   return 0;\n}\n"}]}}
+
+Content-Length: 148
+
+{"jsonrpc":"2.0","id":1,"method":"textDocument/definition","params":{"textDocument":{"uri":"file:///main.cpp"},"position":{"line":5,"character":4}}}
+# Go to struct declaration, new struct instance, qualified name 
+
+Content-Length: 215
+
+{"jsonrpc":"2.0","method":"textDocument/didChange","params":{"textDocument":{"uri":"file:///main.cpp","version":6},"contentChanges":[{"text":"struct Foo {\n  int x;\n};\nint main() {\n   Foo bar;\n   bar.x;\n}\n"}]}}
+
+Content-Length: 148
+
+{"jsonrpc":"2.0","id":1,"method":"textDocument/definition","params":{"textDocument":{"uri":"file:///main.cpp"},"position":{"line":5,"character":7}}}
+# Go to field declaration, field reference 
+
+Content-Length: 220
+
+{"jsonrpc":"2.0","method":"textDocument/didChange","params":{"textDocument":{"uri":"file:///main.cpp","version":7},"contentChanges":[{"text":"struct Foo {\n  void x();\n};\nint main() {\n   Foo bar;\n   bar.x();\n}\n"}]}}
+
+Content-Length: 148
+
+{"jsonrpc":"2.0","id":1,"method":"textDocument/definition","params":{"textDocument":{"uri":"file:///main.cpp"},"position":{"line":5,"character":7}}}
+# Go to method declaration, method call 
+
+Content-Length: 240
+
+{"jsonrpc":"2.0","method":"textDocument/didChange","params":{"textDocument":{"uri":"file:///main.cpp","version":7},"contentChanges":[{"text":"struct Foo {\n};\ntypedef Foo TypedefFoo;\nint main() {\n   TypedefFoo bar;\n   return 0;\n}\n"}]}}
+
+Content-Length: 149
+
+{"jsonrpc":"2.0","id":1,"method":"textDocument/definition","params":{"textDocument":{"uri":"file:///main.cpp"},"position":{"line":4,"character":10}}}
+# Go to typedef 
+
+Content-Length: 254
+
+{"jsonrpc":"2.0","method":"textDocument/didChange","params":{"textDocument":{"uri":"file:///main.cpp","version":7},"contentChanges":[{"text":"template <typename MyTemplateParam>\nvoid foo() {\n MyTemplateParam a;\n}\nint main() {\n   return 0;\n}\n"}]}}
+
+Content-Length: 149
+
+{"jsonrpc":"2.0","id":1,"method":"textDocument/definition","params":{"textDocument":{"uri":"file:///main.cpp"},"position":{"line":2,"character":13}}}
+# Go to template type parameter. Fails until clangIndex is modified to handle those.
+# no-CHECK: {"jsonrpc":"2.0","id":1,"result":[{"uri": "file:///main.cpp", "range": {"start": {"line": 0, "character": 10}, "end": {"line": 0, "character": 34}}}]}
+
+Content-Length: 256
+
+{"jsonrpc":"2.0","method":"textDocument/didChange","params":{"textDocument":{"uri":"file:///main.cpp","version":7},"contentChanges":[{"text":"namespace ns {\nstruct Foo {\nstatic void bar() {}\n};\n}\nint main() {\n   ns::Foo::bar();\n   return 0;\n}\n"}]}}
+
+Content-Length: 148
+
+{"jsonrpc":"2.0","id":1,"method":"textDocument/definition","params":{"textDocument":{"uri":"file:///main.cpp"},"position":{"line":6,"character":4}}}
+# Go to namespace, static method call 
+
+Content-Length: 265
+
+{"jsonrpc":"2.0","method":"textDocument/didChange","params":{"textDocument":{"uri":"file:///main.cpp","version":7},"contentChanges":[{"text":"namespace ns {\nstruct Foo {\n  int field;\n  Foo(int param) : field(param) {}\n};\n}\nint main() {\n   return 0;\n}\n"}]}}
+
+Content-Length: 149
+
+{"jsonrpc":"2.0","id":1,"method":"textDocument/definition","params":{"textDocument":{"uri":"file:///main.cpp"},"position":{"line":3,"character":21}}}
+# Go to field, member initializer 
+
+Content-Length: 204
+
+{"jsonrpc":"2.0","method":"textDocument/didChange","params":{"textDocument":{"uri":"file:///main.cpp","version":7},"contentChanges":[{"text":"#define MY_MACRO 0\nint main() {\n  return MY_MACRO;\n}\n"}]}}
+
+Content-Length: 148
+
+{"jsonrpc":"2.0","id":1,"method":"textDocument/definition","params":{"textDocument":{"uri":"file:///main.cpp"},"position":{"line":2,"character":9}}}
+# Go to macro.
+
+Content-Length: 217
+
+{"jsonrpc":"2.0","method":"textDocument/didChange","params":{"textDocument":{"uri":"file:///main.cpp","version":7},"contentChanges":[{"text":"#define FOO 1\nint a = FOO;\n#define FOO 2\nint b = FOO;\n#undef FOO\n"}]}}
+
+Content-Length: 148
+
+{"jsonrpc":"2.0","id":1,"method":"textDocument/definition","params":{"textDocument":{"uri":"file:///main.cpp"},"position":{"line":1,"character":8}}}
+# Go to macro, re-defined later
+
+Content-Length: 148
+
+{"jsonrpc":"2.0","id":1,"method":"textDocument/definition","params":{"textDocument":{"uri":"file:///main.cpp"},"position":{"line":3,"character":8}}}
+# Go to macro, undefined later
+
+Content-Length: 148
+
+{"jsonrpc":"2.0","id":1,"method":"textDocument/definition","params":{"textDocument":{"uri":"file:///main.cpp"},"position":{"line":4,"character":7}}}
+# Go to macro, being undefined
+
+Content-Length: 44
+
+{"jsonrpc":"2.0","id":3,"method":"shutdown"}