From cf7ac7be7f3831165632e87bd1885ca42c7f51b1 Mon Sep 17 00:00:00 2001
From: Alexander Medvednikov <alexander@vlang.io>
Date: Wed, 24 Jun 2020 12:53:36 +0200
Subject: [PATCH] cgen: zero_struct_field(); orm: zero un-inited fields

---
 vlib/orm/orm_test.v |  1 +
 vlib/v/gen/cgen.v   | 39 ++++++++++++++++++++++++++-------------
 vlib/v/gen/sql.v    | 26 +++++++++++++++++++++-----
 3 files changed, 48 insertions(+), 18 deletions(-)

diff --git a/vlib/orm/orm_test.v b/vlib/orm/orm_test.v
index 5fc481c58c..8bf3587a2f 100644
--- a/vlib/orm/orm_test.v
+++ b/vlib/orm/orm_test.v
@@ -16,6 +16,7 @@ struct User {
 	age int
 	name string
 	is_customer bool
+	skipped_string string [skip]
 }
 
 fn test_orm_sqlite() {
diff --git a/vlib/v/gen/cgen.v b/vlib/v/gen/cgen.v
index 2e2ff78a13..56f96ccc3a 100644
--- a/vlib/v/gen/cgen.v
+++ b/vlib/v/gen/cgen.v
@@ -2531,12 +2531,15 @@ fn (mut g Gen) go_back_out(n int) {
 	g.out.go_back(n)
 }
 
-fn (mut g Gen) struct_init(struct_init ast.StructInit) {
-	skip_init := ['strconv__ftoa__Uf32', 'strconv__ftoa__Uf64', 'strconv__Float64u', 'struct stat',
+const (
+	skip_struct_init = ['strconv__ftoa__Uf32', 'strconv__ftoa__Uf64', 'strconv__Float64u', 'struct stat',
 		'struct addrinfo'
 	]
+)
+
+fn (mut g Gen) struct_init(struct_init ast.StructInit) {
 	styp := g.typ(struct_init.typ)
-	if styp in skip_init {
+	if styp in skip_struct_init {
 		g.go_back_out(3)
 		return
 	}
@@ -2587,13 +2590,15 @@ fn (mut g Gen) struct_init(struct_init ast.StructInit) {
 		}
 	}
 	// The rest of the fields are zeroed.
-	mut nr_info_fields := 0
+	// `inited_fields` is a list of fields that have been init'ed, they are skipped
+	//mut nr_fields := 0
 	if sym.kind == .struct_ {
 		info := sym.info as table.Struct
 		if info.is_union && struct_init.fields.len > 1 {
 			verror('union must not have more than 1 initializer')
 		}
-		nr_info_fields = info.fields.len
+		//g.zero_struct_fields(info, inited_fields)
+		//nr_fields = info.fields.len
 		for field in info.fields {
 			if field.name in inited_fields {
 				sfield := struct_init.fields[inited_fields[field.name]]
@@ -2625,16 +2630,10 @@ fn (mut g Gen) struct_init(struct_init ast.StructInit) {
 				// TODO handle/require optionals in inits
 				continue
 			}
-			field_name := c_name(field.name)
-			g.write('\t.$field_name = ')
-			if field.has_default_expr {
-				g.expr(ast.fe2ex(field.default_expr))
-			} else {
-				g.write(g.type_default(field.typ))
-			}
-			g.writeln(',')
+			g.zero_struct_field(field)
 			initialized = true
 		}
+
 	}
 	// if struct_init.fields.len == 0 && info.fields.len == 0 {
 	if !initialized {
@@ -2646,6 +2645,20 @@ fn (mut g Gen) struct_init(struct_init ast.StructInit) {
 	}
 }
 
+fn (mut g Gen) zero_struct_field(field table.Field) {
+	field_name := c_name(field.name)
+	g.write('\t.$field_name = ')
+	if field.has_default_expr {
+		g.expr(ast.fe2ex(field.default_expr))
+	} else {
+		g.write(g.type_default(field.typ))
+	}
+	g.writeln(',')
+}
+
+//fn (mut g Gen) zero_struct_fields(info table.Struct, inited_fields map[string]int) {
+//}
+
 // { user | name: 'new name' }
 fn (mut g Gen) assoc(node ast.Assoc) {
 	g.writeln('// assoc')
diff --git a/vlib/v/gen/sql.v b/vlib/v/gen/sql.v
index d7525d2865..cccf79b335 100644
--- a/vlib/v/gen/sql.v
+++ b/vlib/v/gen/sql.v
@@ -124,15 +124,31 @@ fn (mut g Gen) sql_select_expr(node ast.SqlExpr) {
 		if node.is_array {
 			// array_User array_tmp;
 			// for { User tmp; ... array_tmp << tmp; }
-			sym := g.table.get_type_symbol(node.typ)
-			info := sym.info as table.Array
-			elem_type_str = g.typ(info.elem_type)
+			array_sym := g.table.get_type_symbol(node.typ)
+			array_info := array_sym.info as table.Array
+			elem_type_str = g.typ(array_info.elem_type)
 			g.writeln('$styp ${tmp}_array = __new_array(0, 10, sizeof($elem_type_str));')
 			g.writeln('while (1) {')
-			g.writeln('\t$elem_type_str $tmp;')
+			g.writeln('\t$elem_type_str $tmp = ($elem_type_str) {')
+			//
+			sym := g.table.get_type_symbol(array_info.elem_type)
+			info :=  sym.info as table.Struct
+			for field in info.fields {
+				g.zero_struct_field(field)
+			}
+			g.writeln('};')
 		} else {
 			// `User tmp;`
-			g.writeln('$styp $tmp;')
+			g.writeln('$styp $tmp = ($styp){')
+			// Zero fields, (only the [skip] ones?)
+			// If we don't, string values are going to be nil etc for fields that are not returned
+			// by the db engine.
+			sym := g.table.get_type_symbol(node.typ)
+			info :=  sym.info as table.Struct
+			for field in info.fields {
+				g.zero_struct_field(field)
+			}
+			g.writeln('};')
 		}
 		//
 		g.writeln('int _step_res$tmp = sqlite3_step($g.sql_stmt_name);')