From 6cbc0e84f0fc4098a897af6d4109040cfe10c4e1 Mon Sep 17 00:00:00 2001
From: yuyi <yuyi98@163.com>
Date: Thu, 2 Jul 2020 17:09:26 +0800
Subject: [PATCH] cgen: fix cross assign with mutable args (fix #5609 #5610
 #5611) (#5614)

---
 vlib/builtin/array_test.v        | 13 ------
 vlib/builtin/map_test.v          |  9 ----
 vlib/v/gen/cgen.v                | 12 ++++-
 vlib/v/tests/cross_assign_test.v | 80 ++++++++++++++++++++++++++++++++
 vlib/v/tests/struct_test.v       | 14 ------
 5 files changed, 91 insertions(+), 37 deletions(-)
 create mode 100644 vlib/v/tests/cross_assign_test.v

diff --git a/vlib/builtin/array_test.v b/vlib/builtin/array_test.v
index 063a04df67..ffde01cce7 100644
--- a/vlib/builtin/array_test.v
+++ b/vlib/builtin/array_test.v
@@ -877,16 +877,3 @@ fn test_plus_assign_string() {
 	a[0] += 'abc'
 	assert a == ['abc']
 }
-
-fn test_cross_assign() {
-	mut a := [0, 1]
-	a[0], a[1] = a[1], a[0]
-	assert a[0] == 1
-	assert a[1] == 0
-
-	mut b1 := [1, 2, 3]
-	mut b2 := 4
-	b1[2], b2, b1[0] = b1[0], b1[2], 5
-	assert b1 == [5, 2, 1]
-	assert b2 == 3
-}
diff --git a/vlib/builtin/map_test.v b/vlib/builtin/map_test.v
index 8fbaa3e0fd..a265e2bc99 100644
--- a/vlib/builtin/map_test.v
+++ b/vlib/builtin/map_test.v
@@ -291,7 +291,6 @@ fn test_plus_assign_string() {
 	assert m['one'] == '1'
 }
 
-
 fn test_map_keys_to_array() {
 	m := {'a': 'b', 'c': 'd'}
 	mut arr := []string{}
@@ -302,11 +301,3 @@ fn test_map_keys_to_array() {
 	println(sarr)
 	assert sarr == "['a', 'c']"
 }
-
-fn test_map_cross_assign() {
-	mut a := {'one':1, 'two':2}
-	a['one'], a['two'] = a['two'], a['one']
-	println(a)
-	assert a['one'] == 2
-	assert a['two'] == 1
-}
diff --git a/vlib/v/gen/cgen.v b/vlib/v/gen/cgen.v
index 146ea20abc..f856e17a55 100644
--- a/vlib/v/gen/cgen.v
+++ b/vlib/v/gen/cgen.v
@@ -1099,6 +1099,9 @@ fn (mut g Gen) gen_assign_stmt(assign_stmt ast.AssignStmt) {
 						info := sym.info as table.Array
 						styp := g.typ(info.elem_type)
 						g.write('$styp _var_$left.pos.pos = *($styp*)array_get(')
+						if left.left_type.is_ptr() {
+							g.write('*')
+						}
 						g.expr(left.left)
 						g.write(', ')
 						g.expr(left.index)
@@ -1108,6 +1111,9 @@ fn (mut g Gen) gen_assign_stmt(assign_stmt ast.AssignStmt) {
 						styp := g.typ(info.value_type)
 						zero := g.type_default(info.value_type)
 						g.write('$styp _var_$left.pos.pos = *($styp*)map_get(')
+						if left.left_type.is_ptr() {
+							g.write('*')
+						}
 						g.expr(left.left)
 						g.write(', ')
 						g.expr(left.index)
@@ -1118,7 +1124,11 @@ fn (mut g Gen) gen_assign_stmt(assign_stmt ast.AssignStmt) {
 					styp := g.typ(left.typ)
 					g.write('$styp _var_$left.pos.pos = ')
 					g.expr(left.expr)
-					g.writeln('.$left.field_name;')
+					if left.expr_type.is_ptr() {
+						g.writeln('->$left.field_name;')
+					} else {
+						g.writeln('.$left.field_name;')
+					}
 				}
 				else {}
 			}
diff --git a/vlib/v/tests/cross_assign_test.v b/vlib/v/tests/cross_assign_test.v
new file mode 100644
index 0000000000..61f3bc1478
--- /dev/null
+++ b/vlib/v/tests/cross_assign_test.v
@@ -0,0 +1,80 @@
+// Test cross assign of array elements
+fn test_cross_assign_of_array() {
+	mut a := [0, 1]
+	a[0], a[1] = a[1], a[0]
+	assert a[0] == 1
+	assert a[1] == 0
+
+	mut b1 := [1, 2, 3]
+	mut b2 := 4
+	b1[2], b2, b1[0] = b1[0], b1[2], 5
+	assert b1 == [5, 2, 1]
+	assert b2 == 3
+}
+
+// Test cross assign of array elements in function
+fn foo1(mut arr []int) {
+	arr[0], arr[1] = arr[1], arr[0]
+}
+
+fn test_cross_assign_of_array_in_fn() {
+	mut arr := [1,2]
+	foo1(mut arr)
+	assert arr[0] == 2
+	assert arr[1] == 1
+}
+
+// Test cross assign of map values
+fn test_cross_assign_of_map() {
+	mut a := {'one':1, 'two':2}
+	a['one'], a['two'] = a['two'], a['one']
+	println(a)
+	assert a['one'] == 2
+	assert a['two'] == 1
+}
+
+// Test cross assign of map values in function
+fn foo2(mut a map[string]int) {
+	a['one'], a['two'] = a['two'], a['one']
+}
+
+fn test_cross_assign_of_map_in_fn() {
+	mut a := {'one':1, 'two':2}
+	foo2(mut a)
+	assert a['one'] == 2
+	assert a['two'] == 1
+}
+
+// Test cross assign of struct fields
+struct Zoo {
+mut:
+	a int
+	b int
+}
+
+fn test_cross_assign_of_struct() {
+	mut x := Zoo{a:1, b:2}
+	x.a, x.b = x.b, x.a
+	//println(x)
+	assert x.a == 2
+	assert x.b == 1
+}
+
+// Test cross assign of struct fields in function
+struct Foo {
+mut:
+	a int
+	b int
+}
+
+fn foo3(mut f &Foo) {
+	f.a, f.b = f.b, f.a
+}
+
+fn test_cross_assign_of_struct_in_fn() {
+	mut a := Foo{a:1, b:2}
+	foo3(mut a)
+	println(a)
+	assert a.a == 2
+	assert a.b == 1
+}
diff --git a/vlib/v/tests/struct_test.v b/vlib/v/tests/struct_test.v
index e6baeaf601..f6695f2097 100644
--- a/vlib/v/tests/struct_test.v
+++ b/vlib/v/tests/struct_test.v
@@ -313,17 +313,3 @@ fn test_struct_with_default_values_no_init() {
 	assert s2.field_optional == 3
 	assert s3.field_optional == 2
 }
-
-struct Zoo {
-mut:
-	a int
-	b int
-}
-
-fn test_struct_field_cross_assign() {
-	mut x := Zoo{a:1, b:2}
-	x.a, x.b = x.b, x.a
-	//println(x)
-	assert x.a == 2
-	assert x.b == 1
-}