fix find declaration for end of identifier

source/workspaced/com/dcd.d

@@ -16,6 +16,7 @@ import std.string;
 import painlessjson;
 
 import workspaced.api;
+import workspaced.helpers;
 
 version (OSX) version = haveUnixSockets;
 version (linux) version = haveUnixSockets;
@@ -330,13 +331,17 @@ class DCDComponent : ComponentWrapper
 		threads.create({
 			try
 			{
-				if (!running)
+				if (!running || pos >= code.length)
 				{
 					ret.finish(DCDDeclaration.init);
 					return;
 				}
-				// Declarations should be returned for character *in front of* the cursor.
-				auto pipes = doClient(["-c", (pos+1).to!string, "--symbolLocation"]);
+
+				// We need to move by one character on identifier characters to ensure the start character fits.
+				if (!isIdentifierSeparatingChar(code[pos]))
+					pos++;
+
+				auto pipes = doClient(["-c", pos.to!string, "--symbolLocation"]);
 				scope (exit)
 				{
 					pipes.pid.wait();

source/workspaced/helpers.d

@@ -50,3 +50,9 @@ ptrdiff_t indexOfKeyword(string code, string keyword, ptrdiff_t start = 0)
 	}
 	return index;
 }
+
+bool isIdentifierSeparatingChar(dchar c)
+{
+	return c < 48 || (c > 57 && c < 65) || c == '[' || c == '\\' || c == ']'
+		|| c == '`' || (c > 122 && c < 128) || c == '\u2028' || c == '\u2029'; // line separators
+}