Add quick fixes for E2 warnings and errors (#2871)

* Add quick fixes for warnings

* Support for multiple changes, Error fixes

* Support multiple replacements
* Quick fix support for Error, although none currently implemented.
* Add (Quick fix available) at the end of a problem instead of changing icon. It's more clear and works for errors too.

* Parser, Preprocessor, Tokenizer support

* Preprocessor rewritten to use traces instead of mostly columns
* Quick fixes to convert `normal` -> `number` for preprocessor
* Quick fixes to convert non CamelCase variables to camelCase in preprocessor
* Parser supports quick fixes now
* Add warning for use of `normal` type in parser (this should really be handled in analyzer, though..)
* Add quick fix for normal use in parser
* Tokenizer supports quick fixes now
* Added invalid escape quick fix (deletes the \)

lua/entities/gmod_wire_expression2/base/compiler.lua

@@ -125,8 +125,9 @@ end
 
 ---@param message string
 ---@param trace Trace
-function Compiler:Error(message, trace)
-	error( Error.new(message, trace), 0)
+---@param quick_fix { replace: string, at: Trace }[]?
+function Compiler:Error(message, trace, quick_fix)
+	error( Error.new(message, trace, nil, quick_fix), 0)
 end
 
 ---@generic T
@@ -152,12 +153,13 @@ end
 
 ---@param message string
 ---@param trace Trace
-function Compiler:Warning(message, trace)
+---@param quick_fix { replace: string, at: Trace }[]?
+function Compiler:Warning(message, trace, quick_fix)
 	if self.include then
 		local tbl = self.warnings[self.include]
-		tbl[#tbl + 1] = Warning.new(message, trace)
+		tbl[#tbl + 1] = Warning.new(message, trace, quick_fix)
 	else
-		self.warnings[#self.warnings + 1] = Warning.new(message, trace)
+		self.warnings[#self.warnings + 1] = Warning.new(message, trace, quick_fix)
 	end
 end
 
@@ -229,11 +231,11 @@ local CompileVisitors = {
 					stmts[i], traces[i] = stmt, trace
 
 					if node:isExpr() and node.variant ~= NodeVariant.ExprDynCall and node.variant ~= NodeVariant.ExprCall and node.variant ~= NodeVariant.ExprMethodCall then
-						self:Warning("This expression has no effect", node.trace)
+						self:Warning("This expression has no effect", node.trace, { { replace = "", at = node.trace } })
 					end
 				end
 			else
-				self:Warning("Unreachable code detected", node.trace)
+				self:Warning("Unreachable code detected", node.trace, { { replace = "", at = node.trace } })
 				break
 			end
 		end
@@ -608,7 +610,7 @@ local CompileVisitors = {
 		if err_ty then
 			self:Assert(err_ty.value == "string", "Error type can only be string, for now", err_ty.trace)
 		else
-			self:Warning("You should explicitly annotate the error type as :string", err_var.trace)
+			self:Warning("You should explicitly annotate the error type as :string", err_var.trace, { { replace = err_var.value .. ":string", at = err_var.trace } })
 		end
 
 		self:Scope(function (scope)
@@ -665,7 +667,7 @@ local CompileVisitors = {
 					self:Error("Variadic parameter requires explicit type", param.name.trace)
 				else
 					param_types[i] = "n"
-					self:Warning("Use of implicit parameter type is deprecated (add :number)", param.name.trace)
+					self:Warning("Use of implicit parameter type is deprecated (add :number)", param.name.trace, { { replace = param.name.value .. ":number", at = param.name.trace } })
 				end
 
 				if param.name.value ~= "_" and existing[param.name.value] then
@@ -1615,6 +1617,11 @@ local CompileVisitors = {
 	---@param data { [1]: Token<string>, [2]: Node[] }
 	[NodeVariant.ExprCall] = function (self, trace, data, used_as_stmt)
 		local name, args, types = data[1], {}, {}
+
+		if name.value == "changed" and data[2][1].variant == NodeVariant.ExprIdent and self.inputs[3][data[2][1].data.value] then
+			self:Warning("Use ~ instead of changed() for inputs", trace, { { replace = "~" .. data[2][1].data.value, at = trace } })
+		end
+
 		for k, arg in ipairs(data[2]) do
 			args[k], types[k] = self:CompileExpr(arg)
 		end
@@ -1903,7 +1910,7 @@ local CompileVisitors = {
 		for i, param in ipairs(data[2]) do
 			local type = param.type and self:CheckType(param.type)
 			if not type then
-				self:Warning("Use of implicit parameter type is deprecated (add :number)", param.name.trace)
+				self:Warning("Use of implicit parameter type is deprecated", param.name.trace, { { replace = param.name.value .. ":number", at = param.name.trace } })
 				type = "n"
 			end
 			params[i] = { param.name.value, type }

lua/entities/gmod_wire_expression2/base/debug.lua

@@ -38,14 +38,15 @@ end
 ---@class Warning
 ---@field message string
 ---@field trace Trace
+---@field quick_fix { replace: string, at: Trace }[]? # Replacements to be made for quick fix
 local Warning = {}
 Warning.__index = Warning
 
 ---@param message string
 ---@param trace Trace
----@return Warning
-function Warning.new(message, trace)
-	return setmetatable({ message = message, trace = trace }, Warning)
+---@param quick_fix { replace: string, at: Trace }[]? # Replacements for quick fix
+function Warning.new(message, trace, quick_fix)
+	return setmetatable({ message = message, trace = trace, quick_fix = quick_fix }, Warning)
 end
 
 function Warning:debug()
@@ -64,15 +65,16 @@ Warning.__tostring = Warning.debug
 ---@field message string
 ---@field trace Trace
 ---@field userdata ErrorUserdata
+---@field quick_fix { replace: string, at: Trace }[]? # Replacements to be made for quick fix
 local Error = {}
 Error.__index = Error
 
 ---@param message string
 ---@param trace Trace?
 ---@param userdata ErrorUserdata?
----@return Error
-function Error.new(message, trace, userdata)
-	return setmetatable({ message = message, trace = trace, userdata = userdata }, Error)
+---@param quick_fix { replace: string, at: Trace }[]? # Replacements to be made for quick fix
+function Error.new(message, trace, userdata, quick_fix)
+	return setmetatable({ message = message, trace = trace, userdata = userdata, quick_fix = quick_fix }, Error)
 end
 
 function Error:debug()

lua/entities/gmod_wire_expression2/base/parser.lua

@@ -178,14 +178,16 @@ end
 
 ---@param message string
 ---@param trace Trace?
-function Parser:Error(message, trace)
-	error( Error.new( message, trace or self:Prev().trace ), 2 )
+---@param quick_fix { replace: string, at: Trace }[]?
+function Parser:Error(message, trace, quick_fix)
+	error( Error.new( message, trace or self:Prev().trace, nil, quick_fix ), 2 )
 end
 
 ---@param message string
 ---@param trace Trace?
-function Parser:Warning(message, trace)
-	self.warnings[#self.warnings + 1] = Warning.new( message, trace or self:Prev().trace )
+---@param quick_fix { replace: string, at: Trace }[]?
+function Parser:Warning(message, trace, quick_fix)
+	self.warnings[#self.warnings + 1] = Warning.new( message, trace or self:Prev().trace, quick_fix )
 end
 
 ---@generic T
@@ -542,6 +544,7 @@ function Parser:Type()
 	local type = self:Consume(TokenVariant.LowerIdent)
 	if type then
 		if type.value == "normal" then
+			self:Warning("Use of deprecated type [normal]", type.trace, { { at = type.trace, replace = "number" } })
 			type.value = "number"
 		end
 	else -- workaround to allow "function" as type while also being a keyword