From 1be5d16f5e1c67ac79ac2af8056bd0b7dbbe965a Mon Sep 17 00:00:00 2001
From: ryuukk <ryuukk.dev@gmail.com>
Date: Thu, 5 Oct 2023 05:26:35 +0200
Subject: [PATCH] Display template parameters for the code completion

---
 dsymbol/src/dsymbol/conversion/first.d  | 36 ++++++++++++++++++++++++-
 dsymbol/src/dsymbol/conversion/second.d |  9 +++----
 dsymbol/src/dsymbol/type_lookup.d       |  2 ++
 3 files changed, 41 insertions(+), 6 deletions(-)

diff --git a/dsymbol/src/dsymbol/conversion/first.d b/dsymbol/src/dsymbol/conversion/first.d
index 196bd22..2d17949 100644
--- a/dsymbol/src/dsymbol/conversion/first.d
+++ b/dsymbol/src/dsymbol/conversion/first.d
@@ -250,10 +250,16 @@ final class FirstPass : ASTVisitor
 	void processTypeIdentifierPart(SemanticSymbol* symbol, TypeLookup* lookup, VariableContext* ctx, VariableContext.TypeInstance* current, TypeIdentifierPart tip)
 	{
 		if (tip.identifierOrTemplateInstance)
+		{
 			processIdentifierOrTemplate(symbol, lookup, ctx, current, tip.identifierOrTemplateInstance);
+			if (current)
+				current.calltip = buildCalltip(tip.identifierOrTemplateInstance.tokens);
+		}
 
 		if (tip.typeIdentifierPart)
+		{
 			processTypeIdentifierPart(symbol, lookup, ctx, current, tip.typeIdentifierPart);
+		}
 
 		// TODO: handle `tip.dot` and `tip.indexer`
 	}
@@ -348,6 +354,31 @@ final class FirstPass : ASTVisitor
 		}
 	}
 
+	string buildCalltip(const(Token)[] tokens)
+	{
+		string calltip;
+		foreach(tk; tokens)
+		{
+			if (tk == tok!"!")
+				calltip ~= "!";
+			else if (tk == tok!"(")
+				calltip ~= "(";
+			else if (tk == tok!")")
+				calltip ~= ")";
+			else if (tk == tok!"[")
+				calltip ~= "[";
+			else if (tk == tok!"]")
+				calltip ~= "]";
+			else if (tk == tok!",")
+				calltip ~= ",";
+			else if (tk == tok!"")
+				calltip ~= " ";
+			else
+				calltip ~= tk.text;
+		}
+		return calltip;
+	}
+
 	void traverseUnaryExpression(SemanticSymbol* symbol, TypeLookup* lookup, VariableContext* ctx, UnaryExpression ue)
 	{
 		if (PrimaryExpression pe = ue.primaryExpression)
@@ -449,8 +480,11 @@ final class FirstPass : ASTVisitor
 			if (dec.type && dec.type.type2 && dec.type.type2.typeIdentifierPart)
 			{
 				TypeIdentifierPart typeIdentifierPart = cast(TypeIdentifierPart) dec.type.type2.typeIdentifierPart;
-
 				lookup.ctx.root = GCAllocator.instance.make!(VariableContext.TypeInstance)();
+
+				if (typeIdentifierPart.identifierOrTemplateInstance)
+					lookup.ctx.calltip = buildCalltip(typeIdentifierPart.identifierOrTemplateInstance.tokens);
+
 				processTypeIdentifierPart(symbol, lookup, &lookup.ctx, lookup.ctx.root, typeIdentifierPart);
 			}
 		}
diff --git a/dsymbol/src/dsymbol/conversion/second.d b/dsymbol/src/dsymbol/conversion/second.d
index 394faa8..7d5c1c4 100644
--- a/dsymbol/src/dsymbol/conversion/second.d
+++ b/dsymbol/src/dsymbol/conversion/second.d
@@ -35,6 +35,7 @@ import dparse.ast;
 import dparse.lexer;
 import std.algorithm : filter;
 import std.range;
+import std.stdio;
 
 void secondPass(SemanticSymbol* currentSymbol, Scope* moduleScope, ref ModuleCache cache)
 {
@@ -165,13 +166,12 @@ DSymbol* createTypeWithTemplateArgs(DSymbol* type, TypeLookup* lookup, VariableC
 {
 	assert(type);
 	DSymbol* newType = GCAllocator.instance.make!DSymbol("dummy", CompletionKind.dummy, null);
-	newType.name = type.name;
+	newType.name = ti ? istring(ti.calltip) : istring(lookup.ctx.calltip);
 	newType.kind = type.kind;
 	newType.qualifier = type.qualifier;
 	newType.protection = type.protection;
 	newType.symbolFile = type.symbolFile;
 	newType.doc = type.doc;
-	newType.callTip = type.callTip;
 	newType.type = type.type;
 	DSymbol*[string] mapping;
 
@@ -189,7 +189,6 @@ DSymbol* createTypeWithTemplateArgs(DSymbol* type, TypeLookup* lookup, VariableC
 					continue;
 				}
 				auto key = part.name;
-				
 				DSymbol* first;
 				bool isBuiltin;
 				foreach(i, crumb; ti.args[count].chain)
@@ -233,7 +232,6 @@ DSymbol* createTypeWithTemplateArgs(DSymbol* type, TypeLookup* lookup, VariableC
 			}
 		}
 	}
-	
 
 	// HACK: to support functions with template arguments that return a generic type
 	// first.d in processParameters only store the function's return type in the callTip
@@ -334,7 +332,7 @@ void resolveTemplate(DSymbol* variableSym, DSymbol* type, TypeLookup* lookup, Va
 	if (current.chain.length == 0) return; // TODO: should not be empty, happens for simple stuff Inner inner;
 
 	DSymbol* newType = createTypeWithTemplateArgs(type, lookup, current, cache, moduleScope, depth, mapping);
-	
+	//writeln(">>", variableSym.name, " > ", newType.name);
 	variableSym.type = newType;
 	variableSym.ownType = true;
 }
@@ -524,6 +522,7 @@ do
 		suffix.ownType = false;
 		symbol.type = lastSuffix;
 		symbol.ownType = true;
+
 		if (currentSymbol is null && !remainingImports.empty)
 		{
 			//			info("Deferring type resolution for ", symbol.name);
diff --git a/dsymbol/src/dsymbol/type_lookup.d b/dsymbol/src/dsymbol/type_lookup.d
index c417c53..3619024 100644
--- a/dsymbol/src/dsymbol/type_lookup.d
+++ b/dsymbol/src/dsymbol/type_lookup.d
@@ -48,6 +48,8 @@ struct VariableContext
 		string[] chain;
 		TypeInstance*[] args;
 		string name;
+		string calltip;
 	}
 	TypeInstance* root;
+	string calltip;
 }
\ No newline at end of file