From 2b058edc989ace96e0795e54022583b89b113755 Mon Sep 17 00:00:00 2001
From: Alexander Medvednikov <alexander@vlang.io>
Date: Sun, 17 Jan 2021 06:24:03 +0100
Subject: [PATCH] checker: do not require ref field init with update expr

---
 vlib/v/checker/checker.v | 52 +++++++++++++++++++++-------------------
 vlib/v/parser/comptime.v |  9 ++++---
 2 files changed, 34 insertions(+), 27 deletions(-)

diff --git a/vlib/v/checker/checker.v b/vlib/v/checker/checker.v
index b9299fbcc4..52e8fc3b90 100644
--- a/vlib/v/checker/checker.v
+++ b/vlib/v/checker/checker.v
@@ -633,7 +633,7 @@ pub fn (mut c Checker) struct_init(mut struct_init ast.StructInit) table.Type {
 				if field.has_default_expr || field.name in inited_fields {
 					continue
 				}
-				if field.typ.is_ptr() && !c.pref.translated {
+				if field.typ.is_ptr() && !struct_init.has_update_expr && !c.pref.translated {
 					c.error('reference field `${type_sym.name}.$field.name` must be initialized',
 						struct_init.pos)
 				}
@@ -3299,29 +3299,7 @@ pub fn (mut c Checker) expr(node ast.Expr) table.Type {
 			return c.at_expr(mut node)
 		}
 		ast.ComptimeCall {
-			node.sym = c.table.get_type_symbol(c.unwrap_generic(c.expr(node.left)))
-			if node.is_embed {
-				c.file.embedded_files << node.embed_file
-				return c.table.find_type_idx('v.embed_file.EmbedFileData')
-			}
-			if node.is_vweb {
-				// TODO assoc parser bug
-				pref := *c.pref
-				pref2 := {
-					pref |
-					is_vweb: true
-				}
-				mut c2 := new_checker(c.table, pref2)
-				c2.check(node.vweb_tmpl)
-				c.warnings << c2.warnings
-				c.errors << c2.errors
-				c.nr_warnings += c2.nr_warnings
-				c.nr_errors += c2.nr_errors
-			}
-			if node.method_name == 'html' {
-				return c.table.find_type_idx('vweb.Result')
-			}
-			return table.string_type
+			return c.comptime_call(mut node)
 		}
 		ast.ComptimeSelector {
 			node.left_type = c.unwrap_generic(c.expr(node.left))
@@ -3556,6 +3534,32 @@ pub fn (mut c Checker) cast_expr(mut node ast.CastExpr) table.Type {
 	return node.typ
 }
 
+fn (mut c Checker) comptime_call(mut node ast.ComptimeCall) table.Type {
+	node.sym = c.table.get_type_symbol(c.unwrap_generic(c.expr(node.left)))
+	if node.is_embed {
+		c.file.embedded_files << node.embed_file
+		return c.table.find_type_idx('v.embed_file.EmbedFileData')
+	}
+	if node.is_vweb {
+		// TODO assoc parser bug
+		pref := *c.pref
+		pref2 := {
+			pref |
+			is_vweb: true
+		}
+		mut c2 := new_checker(c.table, pref2)
+		c2.check(node.vweb_tmpl)
+		c.warnings << c2.warnings
+		c.errors << c2.errors
+		c.nr_warnings += c2.nr_warnings
+		c.nr_errors += c2.nr_errors
+	}
+	if node.method_name == 'html' {
+		return c.table.find_type_idx('vweb.Result')
+	}
+	return table.string_type
+}
+
 fn (mut c Checker) at_expr(mut node ast.AtExpr) table.Type {
 	match node.kind {
 		.fn_name {
diff --git a/vlib/v/parser/comptime.v b/vlib/v/parser/comptime.v
index 85da8c818c..26f4adf37b 100644
--- a/vlib/v/parser/comptime.v
+++ b/vlib/v/parser/comptime.v
@@ -156,8 +156,8 @@ fn (mut p Parser) comp_call() ast.ComptimeCall {
 		println('\n\n')
 	}
 	mut file := parse_comptime(v_code, p.table, p.pref, scope, p.global_scope)
-	file = {
-		file |
+	file = ast.File{
+		...file
 		path: tmpl_path
 	}
 	// copy vars from current fn scope into vweb_tmpl scope
@@ -170,7 +170,10 @@ fn (mut p Parser) comp_call() ast.ComptimeCall {
 					if obj is ast.Var {
 						mut v := obj
 						v.pos = stmt.body_pos
-						tmpl_scope.register(v)
+						tmpl_scope.register(ast.Var{
+							...v
+							is_used: true
+						})
 						// set the controller action var to used
 						// if it's unused in the template it will warn
 						v.is_used = true