make byte(0) an error; use u8(0)

vlib/v/checker/assign.v

@@ -870,7 +870,7 @@ or use an explicit `unsafe{ a[..] }`, if you do not want a copy of the slice.',
 			c.error('cannot assign anonymous `struct` to a typed `struct`', right.pos())
 		}
 		if right_sym.kind == .alias && right_sym.name == 'byte' {
-			c.warn('byte is deprecated, use u8 instead', right.pos())
+			c.error('byte is deprecated, use u8 instead', right.pos())
 		}
 	}
 	// this needs to run after the assign stmt left exprs have been run through checker

vlib/v/checker/checker.v

@@ -36,7 +36,7 @@ pub const fixed_array_builtin_methods = ['contains', 'index', 'any', 'all', 'wai
 	'sorted', 'sort_with_compare', 'sorted_with_compare', 'reverse', 'reverse_in_place', 'count']
 pub const fixed_array_builtin_methods_chk = token.new_keywords_matcher_from_array_trie(fixed_array_builtin_methods)
 // TODO: remove `byte` from this list when it is no longer supported
-pub const reserved_type_names = ['byte', 'bool', 'char', 'i8', 'i16', 'int', 'i64', 'u8', 'u16',
+pub const reserved_type_names = ['bool', 'char', 'i8', 'i16', 'int', 'i64', 'u8', 'u16',
 	'u32', 'u64', 'f32', 'f64', 'map', 'string', 'rune', 'usize', 'isize', 'voidptr', 'thread']
 pub const reserved_type_names_chk = token.new_keywords_matcher_from_array_trie(reserved_type_names)
 pub const vroot_is_deprecated_message = '@VROOT is deprecated, use @VMODROOT or @VEXEROOT instead'

vlib/v/checker/containers.v

@@ -61,7 +61,7 @@ fn (mut c Checker) array_init(mut node ast.ArrayInit) ast.Type {
 				}
 				ast.Alias {
 					if elem_sym.name == 'byte' {
-						c.warn('byte is deprecated, use u8 instead', node.elem_type_pos)
+						c.error('byte is deprecated, use u8 instead', node.elem_type_pos)
 					}
 				}
 				ast.Map {

vlib/v/checker/fn.v

@@ -167,7 +167,7 @@ fn (mut c Checker) fn_decl(mut node ast.FnDecl) {
 					parent_sym.info.size_expr, true)
 			}
 			if return_sym.name == 'byte' {
-				c.warn('byte is deprecated, use u8 instead', node.return_type_pos)
+				c.error('byte is deprecated, use u8 instead', node.return_type_pos)
 			}
 		}
 		if return_sym.info is ast.ArrayFixed && c.array_fixed_has_unresolved_size(return_sym.info) {
@@ -337,7 +337,7 @@ fn (mut c Checker) fn_decl(mut node ast.FnDecl) {
 				c.error('duplicate of an import symbol `${param.name}`', param.pos)
 			}
 			if arg_typ_sym.kind == .alias && arg_typ_sym.name == 'byte' {
-				c.warn('byte is deprecated, use u8 instead', param.type_pos)
+				c.error('byte is deprecated, use u8 instead', param.type_pos)
 			}
 		}
 		if !node.is_method {

vlib/v/checker/struct.v

@@ -220,7 +220,7 @@ fn (mut c Checker) struct_decl(mut node ast.StructDecl) {
 				}
 				.alias {
 					if sym.name == 'byte' {
-						c.warn('byte is deprecated, use u8 instead', field.type_pos)
+						c.error('byte is deprecated, use u8 instead', field.type_pos)
 					}
 				}
 				else {

vlib/v/checker/tests/dump_char.out

@@ -1,5 +1,5 @@
 vlib/v/checker/tests/dump_char.vv:3:6: error: `char` values cannot be dumped directly, use dump(u8(x)) or dump(int(x)) instead
     1 | c := char(67)
-    2 | dump(byte(c))
+    2 | dump(u8(c))
     3 | dump(c)
       |      ^

vlib/v/checker/tests/dump_char.vv

@@ -1,3 +1,3 @@
 c := char(67)
-dump(byte(c))
+dump(u8(c))
 dump(c)

vlib/v/checker/tests/struct_type_cast_err.out

@@ -1,10 +1,3 @@
-vlib/v/checker/tests/struct_type_cast_err.vv:10:7: warning: byte is deprecated, use u8 instead
-    8 |     _ := u32(foo)
-    9 |     _ := rune(foo)
-   10 |     _ := byte(foo)
-      |          ~~~~~~~~~
-   11 |     _ := i8(foo)
-   12 |     _ := i64(foo)
 vlib/v/checker/tests/struct_type_cast_err.vv:5:7: error: cannot cast struct `Foo` to `string`
     3 | fn main() {
     4 |     foo := Foo{}
@@ -32,30 +25,30 @@ vlib/v/checker/tests/struct_type_cast_err.vv:8:7: error: cannot cast struct `Foo
     8 |     _ := u32(foo)
       |          ~~~~~~~~
     9 |     _ := rune(foo)
-   10 |     _ := byte(foo)
+   10 |     _ := u8(foo)
 vlib/v/checker/tests/struct_type_cast_err.vv:9:7: error: cannot cast struct `Foo` to `rune`
     7 |     _ := u64(foo)
     8 |     _ := u32(foo)
     9 |     _ := rune(foo)
       |          ~~~~~~~~~
-   10 |     _ := byte(foo)
+   10 |     _ := u8(foo)
    11 |     _ := i8(foo)
-vlib/v/checker/tests/struct_type_cast_err.vv:10:7: error: cannot cast `Foo` to `byte` (alias to `u8`)
+vlib/v/checker/tests/struct_type_cast_err.vv:10:7: error: cannot cast struct `Foo` to `u8`
     8 |     _ := u32(foo)
     9 |     _ := rune(foo)
-   10 |     _ := byte(foo)
-      |          ~~~~~~~~~
+   10 |     _ := u8(foo)
+      |          ~~~~~~~
    11 |     _ := i8(foo)
    12 |     _ := i64(foo)
 vlib/v/checker/tests/struct_type_cast_err.vv:11:7: error: cannot cast struct `Foo` to `i8`
     9 |     _ := rune(foo)
-   10 |     _ := byte(foo)
+   10 |     _ := u8(foo)
    11 |     _ := i8(foo)
       |          ~~~~~~~
    12 |     _ := i64(foo)
    13 |     _ := int(foo)
 vlib/v/checker/tests/struct_type_cast_err.vv:12:7: error: cannot cast struct `Foo` to `i64`
-   10 |     _ := byte(foo)
+   10 |     _ := u8(foo)
    11 |     _ := i8(foo)
    12 |     _ := i64(foo)
       |          ~~~~~~~~

vlib/v/checker/tests/struct_type_cast_err.vv

@@ -7,7 +7,7 @@ fn main() {
 	_ := u64(foo)
 	_ := u32(foo)
 	_ := rune(foo)
-	_ := byte(foo)
+	_ := u8(foo)
 	_ := i8(foo)
 	_ := i64(foo)
 	_ := int(foo)

vlib/v/checker/tests/top_level_fn_builtin_decl_err.out

@@ -1,61 +1,55 @@
-vlib/v/checker/tests/top_level_fn_builtin_decl_err.vv:2:12: warning: byte is deprecated, use u8 instead
-    1 | @[inline]
-    2 | fn char(ch byte) fn (string) !(byte, string) {
-      |            ~~~~
-    3 |     return fn [ch] (input string) !(byte, string) {
-    4 |         return if input[0] == ch {
 vlib/v/checker/tests/top_level_fn_builtin_decl_err.vv:2:1: error: top level declaration cannot shadow builtin type
     1 | @[inline]
-    2 | fn char(ch byte) fn (string) !(byte, string) {
-      | ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
-    3 |     return fn [ch] (input string) !(byte, string) {
+    2 | fn char(ch u8) fn (string) !(u8, string) {
+      | ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
+    3 |     return fn [ch] (input string) !(u8, string) {
     4 |         return if input[0] == ch {
 vlib/v/checker/tests/top_level_fn_builtin_decl_err.vv:18:18: error: unknown function: a_char
-   16 | 
+   16 |
    17 |     for i, input in inputs {
    18 |         got, remain := a_char(input)!
       |                        ~~~~~~~~~~~~~
-   19 | 
+   19 |
    20 |         assert got == 'a'[0]
 vlib/v/checker/tests/top_level_fn_builtin_decl_err.vv:18:31: error: unexpected `!`, the function `a_char` does not return a Result
-   16 | 
+   16 |
    17 |     for i, input in inputs {
    18 |         got, remain := a_char(input)!
       |                                     ^
-   19 | 
+   19 |
    20 |         assert got == 'a'[0]
 vlib/v/checker/tests/top_level_fn_builtin_decl_err.vv:18:15: error: assignment mismatch: 2 variables but `a_char()` returns 0 values
-   16 | 
+   16 |
    17 |     for i, input in inputs {
    18 |         got, remain := a_char(input)!
       |                     ~~
-   19 | 
+   19 |
    20 |         assert got == 'a'[0]
 vlib/v/checker/tests/top_level_fn_builtin_decl_err.vv:20:10: error: invalid variable `got`
    18 |         got, remain := a_char(input)!
-   19 | 
+   19 |
    20 |         assert got == 'a'[0]
       |                ~~~
    21 |         assert remain == remains[i]
    22 |     }
 vlib/v/checker/tests/top_level_fn_builtin_decl_err.vv:20:10: error: assert can be used only with `bool` expressions, but found `void` instead
    18 |         got, remain := a_char(input)!
-   19 | 
+   19 |
    20 |         assert got == 'a'[0]
       |                ~~~~~~~~~~~~~
    21 |         assert remain == remains[i]
    22 |     }
 vlib/v/checker/tests/top_level_fn_builtin_decl_err.vv:21:10: error: invalid variable `remain`
-   19 | 
+   19 |
    20 |         assert got == 'a'[0]
    21 |         assert remain == remains[i]
       |                ~~~~~~
    22 |     }
    23 | }
 vlib/v/checker/tests/top_level_fn_builtin_decl_err.vv:21:10: error: assert can be used only with `bool` expressions, but found `void` instead
-   19 | 
+   19 |
    20 |         assert got == 'a'[0]
    21 |         assert remain == remains[i]
       |                ~~~~~~~~~~~~~~~~~~~~
    22 |     }
-   23 | }
+   23 | }

vlib/v/checker/tests/top_level_fn_builtin_decl_err.vv

@@ -1,6 +1,6 @@
 @[inline]
-fn char(ch byte) fn (string) !(byte, string) {
-	return fn [ch] (input string) !(byte, string) {
+fn char(ch u8) fn (string) !(u8, string) {
+	return fn [ch] (input string) !(u8, string) {
 		return if input[0] == ch {
 			ch, input[1..]
 		} else {

vlib/v/checker/tests/use_byte_instead_of_u8_err.out

@@ -0,0 +1,25 @@
+vlib/v/checker/tests/use_byte_instead_of_u8_err.vv:1:13: error: type `byte` is an alias, use the original alias type `u8` instead
+    1 | type Byte = byte
+      |             ~~~~
+    2 |
+    3 | fn foo(_ byte) {}
+vlib/v/checker/tests/use_byte_instead_of_u8_err.vv:3:10: error: byte is deprecated, use u8 instead
+    1 | type Byte = byte
+    2 |
+    3 | fn foo(_ byte) {}
+      |          ~~~~
+    4 |
+    5 | fn main() {
+vlib/v/checker/tests/use_byte_instead_of_u8_err.vv:6:7: error: byte is deprecated, use u8 instead
+    4 |
+    5 | fn main() {
+    6 |     _ := byte(0)
+      |          ~~~~~~~
+    7 |     _ := fn(_ byte) {}
+    8 | }
+vlib/v/checker/tests/use_byte_instead_of_u8_err.vv:7:12: error: byte is deprecated, use u8 instead
+    5 | fn main() {
+    6 |     _ := byte(0)
+    7 |     _ := fn(_ byte) {}
+      |               ~~~~
+    8 | }

vlib/v/checker/tests/use_byte_instead_of_u8_err.vv

@@ -0,0 +1,8 @@
+type Byte = byte
+
+fn foo(_ byte) {}
+
+fn main() {
+	_ := byte(0)
+	_ := fn(_ byte) {}
+}

vlib/v/fmt/tests/import_selective_keep.vv

@@ -11,6 +11,6 @@ fn generic[T]() {}
 
 fn main() {
 	_ := Duration(10) // keep cast type
-	assert *(&f64(&byte(&num) + __offsetof(Complex, re))) == 1.0
+	assert *(&f64(&u8(&num) + __offsetof(Complex, re))) == 1.0
 	generic[Test]()
 }

vlib/v/fmt/tests/pointer_casts_keep.vv

@@ -5,10 +5,10 @@ struct Struct {
 
 fn main() {
 	unsafe {
-		pb := &byte(0)
-		ppb := &&byte(0)
-		pppb := &&&byte(0)
-		ppppb := &&&&byte(0)
+		pb := &u8(0)
+		ppb := &&u8(0)
+		pppb := &&&u8(0)
+		ppppb := &&&&u8(0)
 		dump(voidptr(pb))
 		dump(voidptr(ppb))
 		dump(voidptr(pppb))