parser: fix enum default value in struct

* parser: fix enum default value in struct

* Add a test for the enum default values in structs.

* Fix compilation of vfmt.

* Run vfmt over enum_default_value_in_struct_test.v

* Cleanup spurious , in vfmt output for enum declarations

Co-authored-by: Delyan Angelov <delian66@gmail.com>

cmd/tools/vfmt.v

@@ -144,7 +144,6 @@ fn main() {
 		}
 		exit(1)
 	}
-	println('vfmt done')
 }
 
 fn (foptions &FormatOptions) format_file(file string) {

vlib/v/ast/ast.v

@@ -101,13 +101,14 @@ pub:
 
 pub struct StructField {
 pub:
-	name         string
-	pos          token.Position
-	comment      Comment
-	default_expr string // token literal //Expr
-	attr string
+	name             string
+	pos              token.Position
+	comment          Comment
+	default_expr     Expr
+	has_default_expr bool
+	attr             string
 mut:
-	typ          table.Type
+	typ              table.Type
 }
 
 pub struct Field {

vlib/v/ast/str.v

@@ -136,6 +136,9 @@ pub fn (x Expr) str() string {
 		TypeOf {
 			return 'typeof(${it.expr.str()})'
 		}
+		EnumVal {
+			return '.${it.val}'
+		}
 		CallExpr {
 			sargs := args2str(it.args)
 			if it.is_method {

vlib/v/fmt/fmt.v

@@ -216,10 +216,8 @@ fn (f mut Fmt) stmt(node ast.Stmt) {
 				if field.has_expr {
 					f.write(' = ')
 					f.expr(field.expr)
-					f.writeln(',')
-				} else {
-					f.writeln('')
 				}
+				f.writeln('')
 			}
 			f.writeln('}\n')
 		}
@@ -407,8 +405,8 @@ fn (f mut Fmt) struct_decl(node ast.StructDecl) {
 		f.write('\t$field.name ')
 		f.write(strings.repeat(` `, max - field.name.len))
 		f.write(f.type_to_str(field.typ))
-		if field.default_expr != '' {
-			f.write(' = $field.default_expr')
+		if field.has_default_expr {
+			f.write(' = ${field.default_expr.str()}')
 		}
 		// f.write('// $field.pos.line_nr')
 		if field.comment.text != '' && field.comment.pos.line_nr == field.pos.line_nr {

vlib/v/gen/cgen.v

@@ -1077,10 +1077,9 @@ fn (g mut Gen) expr(node ast.Expr) {
 			g.write("'$it.val'")
 		}
 		ast.EnumVal {
-			// g.write('/*EnumVal*/${it.mod}${it.enum_name}_$it.val')
+			// g.write('${it.mod}${it.enum_name}_$it.val')
 			styp := g.typ(it.typ)
-			g.write(styp)
-			g.write('_$it.val')
+			g.write('${styp}_$it.val')
 		}
 		ast.FloatLiteral {
 			g.write(it.val)
@@ -1971,17 +1970,17 @@ fn (g mut Gen) const_decl_simple_define(name, val string) {
 	g.definitions.writeln(val)
 }
 
-fn (g mut Gen) struct_init(it ast.StructInit) {
+fn (g mut Gen) struct_init(struct_init ast.StructInit) {
 	mut info := table.Struct{}
 	mut is_struct := false
-	sym := g.table.get_type_symbol(it.typ)
+	sym := g.table.get_type_symbol(struct_init.typ)
 	if sym.kind == .struct_ {
 		is_struct = true
 		info = sym.info as table.Struct
 	}
 	// info := g.table.get_type_symbol(it.typ).info as table.Struct
 	// println(info.fields.len)
-	styp := g.typ(it.typ)
+	styp := g.typ(struct_init.typ)
 	is_amp := g.is_amp
 	if is_amp {
 		g.out.go_back(1)		// delete the & already generated in `prefix_expr()
@@ -1991,20 +1990,20 @@ fn (g mut Gen) struct_init(it ast.StructInit) {
 	}
 	mut fields := []string
 	mut inited_fields := []string	// TODO this is done in checker, move to ast node
-	if it.fields.len == 0 && it.exprs.len > 0 {
+	if struct_init.fields.len == 0 && struct_init.exprs.len > 0 {
 		// Get fields for {a,b} short syntax. Fields array wasn't set in the parser.
 		for f in info.fields {
 			fields << f.name
 		}
 	} else {
-		fields = it.fields
+		fields = struct_init.fields
 	}
-	// / User set fields
+	// User set fields
 	for i, field in fields {
 		field_name := c_name(field)
 		inited_fields << field
 		g.write('\t.$field_name = ')
-		g.expr_with_cast(it.exprs[i], it.expr_types[i], it.expected_types[i])
+		g.expr_with_cast(struct_init.exprs[i], struct_init.expr_types[i], struct_init.expected_types[i])
 		g.writeln(',')
 	}
 	// The rest of the fields are zeroed.
@@ -2018,11 +2017,16 @@ fn (g mut Gen) struct_init(it ast.StructInit) {
 				continue
 			}
 			field_name := c_name(field.name)
-			zero := if field.default_val != '' { field.default_val } else { g.type_default(field.typ) }
-			g.writeln('\t.$field_name = $zero,')			// zer0')
+			if field.has_default_expr {
+				g.expr(field.default_expr)
+				g.writeln(',')
+			} else {
+				zero := g.type_default(field.typ)
+				g.writeln('\t.$field_name = $zero,')
+			}
 		}
 	}
-	if it.fields.len == 0 && info.fields.len == 0 {
+	if struct_init.fields.len == 0 && info.fields.len == 0 {
 		g.write('0')
 	}
 	g.write('}')

vlib/v/parser/parser.v

@@ -1555,13 +1555,20 @@ fn (p mut Parser) struct_decl() ast.StructDecl {
 			println('XXXX' + s.str())
 		}
 */
-			mut default_expr := ''			// ast.Expr{}
+			mut default_expr := ast.Expr{}
+			mut has_default_expr := false
 			if p.tok.kind == .assign {
 				// Default value
 				p.next()
-				default_expr = p.tok.lit
-				p.expr(0)
-				// default_expr = p.expr(0)
+				// default_expr = p.tok.lit
+				// p.expr(0)
+				default_expr = p.expr(0)
+				match default_expr {
+					ast.EnumVal { it.typ = typ }
+					// TODO: implement all types??
+					else {}
+				}
+				has_default_expr = true
 			}
 			if p.tok.kind == .comment {
 				comment = p.comment()
@@ -1572,11 +1579,13 @@ fn (p mut Parser) struct_decl() ast.StructDecl {
 				typ: typ
 				comment: comment
 				default_expr: default_expr
+				has_default_expr: has_default_expr
 			}
 			fields << table.Field{
 				name: field_name
 				typ: typ
-				default_val: default_expr
+				default_expr: default_expr
+				has_default_expr: has_default_expr
 			}
 			// println('struct field $ti.name $field_name')
 		}

vlib/v/table/atypes.v

@@ -559,6 +559,8 @@ pub:
 	name string
 mut:
 	typ  Type
+	default_expr ast.Expr
+	has_default_expr bool
 	default_val string
 }
 

vlib/v/tests/enum_default_value_in_struct_test.v

@@ -0,0 +1,28 @@
+pub enum MyEnum {
+	first = 20
+	second
+	third
+}
+
+pub struct MyStruct {
+mut:
+	e MyEnum = .second
+}
+
+fn test_enum_first_value() {
+	assert MyEnum.first == 20
+}
+
+fn test_enum_default_value() {
+	d := MyStruct{}
+	assert int(d.e) == 21
+	assert 'd.e: $d.e | int(d.e): ${int(d.e).str()}' == 'd.e: second | int(d.e): 21'
+}
+
+fn test_enum_non_default_value() {
+	t := MyStruct{
+		e: .third
+	}
+	assert int(t.e) == 22
+	assert 't.e: $t.e | int(t.e): ${int(t.e).str()}' == 't.e: third | int(t.e): 22'
+}