fmt: single line if

vlib/v/fmt/fmt.v

@@ -22,6 +22,7 @@ mut:
 	indent         int
 	empty_line     bool
 	line_len       int
+	single_line_if bool
 }
 
 pub fn fmt(file ast.File, table &table.Table) string {
@@ -130,8 +131,10 @@ fn (f mut Fmt) stmt(node ast.Stmt) {
 		}
 		ast.ExprStmt {
 			f.expr(it.expr)
+			if !f.single_line_if {
 				f.writeln('')
 			}
+		}
 		ast.FnDecl {
 			f.write(it.str(f.table))
 			f.writeln(' {')
@@ -241,16 +244,36 @@ fn (f mut Fmt) expr(node ast.Expr) {
 			f.write(it.val)
 		}
 		ast.IfExpr {
+			single_line := it.stmts.len == 1 && it.else_stmts.len == 1 && it.typ != table.void_type
+			f.single_line_if = single_line
 			f.write('if ')
 			f.expr(it.cond)
+			if single_line {
+				f.write(' { ')
+			}
+			else {
 				f.writeln(' {')
+			}
 			f.stmts(it.stmts)
+			if single_line {
+				f.write(' ')
+			}
 			f.write('}')
 			if it.else_stmts.len > 0 {
-				f.writeln(' else {')
+				f.write(' else {')
+				if single_line {
+					f.write(' ')
+				}
+				else {
+					f.writeln('')
+				}
 				f.stmts(it.else_stmts)
+				if single_line {
+					f.write(' ')
+				}
 				f.write('}')
 			}
+			f.single_line_if = false
 		}
 		ast.Ident {
 			f.write('$it.name')

vlib/v/fmt/tests/simple_expected.vv

@@ -66,5 +66,6 @@ fn fn_with_3_args(arg1 string, arg2 int, arg3 User) int {
 }
 
 fn (this User) fn_with_receiver() {
+	x := if true { 1 } else { 2 }
 	println('')
 }

vlib/v/fmt/tests/simple_input.vv

@@ -70,6 +70,7 @@ return 0
 }
 
 fn    (this User) fn_with_receiver() {
+	x := if true {1} else {2}
 println('')
 }