[clangd][tests] Fix delimiter handling

[jkorous]

Summary

Empty line shouldn't be considered a delimiter.

Following https://reviews.llvm.org/D45763

[jkorous]

Hi Sam, could you please take a look at this minor fix?

[sammccall]

Oops, thanks! LG, optional suggestion

JSONRPCDispatcher.cpp

281 ↗

(On Diff #142918)

This trades one gotcha (empty lines delimit) for another (---- looks valid, but isn't).
What about adding LineRef.startswith("-") to the original check?

[jkorous]

[ultranit] Sorry, just to be sure - did you really mean any number of dashes

if (LineRef.startswith("-") && LineRef.find_first_not_of('-') == llvm::StringRef::npos)

or at least three?

if (LineRef.startswith("---") && LineRef.find_first_not_of('-') == llvm::StringRef::npos)

[sammccall]

In D45764#1072067, @jkorous wrote:

[ultranit] Sorry, just to be sure - did you really mean any number of dashes

if (LineRef.startswith("-") && LineRef.find_first_not_of('-') == llvm::StringRef::npos)

or at least three?

if (LineRef.startswith("---") && LineRef.find_first_not_of('-') == llvm::StringRef::npos)

I meant any number, but at-least-three is fine too! Up to you.

clang-tools-extra/trunk/clangd/JSONRPCDispatcher.cpp

static llvm::Optional<std::string> readDelimitedMessage(std::istream &In,
   while (std::getline(In, Line)) {
     Line.push_back('\n'); // getline() consumed the newline.
 
     auto LineRef = llvm::StringRef(Line).trim();
     if (LineRef.startswith("#")) // comment
       continue;
 
     // found a delimiter
-    if (LineRef.find_first_not_of('-') == llvm::StringRef::npos)
+    if (LineRef.rtrim() == "---")
       break;
 
     JSON += Line;
   }
 
   if (In.bad()) {
     log("Input error while reading message!");
     return llvm::None;

clang-tools-extra/trunk/test/clangd/spaces-in-delimited-input.test

+# RUN: clangd -input-style=delimited -run-synchronously < %s 2>&1 | FileCheck %s
+# RUN: clangd -lit-test -run-synchronously < %s 2>&1 | FileCheck %s
+#
+{"jsonrpc":"2.0","id":0,"method":"initialize","params":{"processId":123,"rootPath":"clangd","capabilities":{},"trace":"off"}}
+
+---
+
+{"jsonrpc":"2.0","id":3,"method":"shutdown"}
+
+---
+
+{"jsonrpc":"2.0","id":3,"method":"exit"}
+# CHECK-NOT: JSON parse error