parser: parse -1 and -13.3 as number literals (#8321)

vlib/v/checker/checker.v

@@ -2445,26 +2445,15 @@ pub fn (mut c Checker) assign_stmt(mut assign_stmt ast.AssignStmt) {
 		if is_decl {
 			left_type = c.table.mktyp(right_type)
 			if left_type == table.int_type {
-				mut expr := right
-				mut negative := false
-				if right is ast.PrefixExpr {
-					expr = right.right
-					if right.op == .minus {
-						negative = true
-					}
-				}
-				if mut expr is ast.IntegerLiteral {
-					mut is_large := false
-					if expr.val.len > 8 {
-						val := expr.val.i64()
-						if (!negative && val > checker.int_max)
-							|| (negative && -val < checker.int_min) {
-							is_large = true
-						}
+				if right is ast.IntegerLiteral {
+					mut is_large := right.val.len > 13
+					if !is_large && right.val.len > 8 {
+						val := right.val.i64()
+						is_large = val > checker.int_max || val < checker.int_min
 					}
 					if is_large {
 						c.error('overflow in implicit type `int`, use explicit type casting instead',
-							expr.pos)
+							right.pos)
 					}
 				}
 			}
@@ -4886,12 +4875,9 @@ fn (mut c Checker) check_index(typ_sym &table.TypeSymbol, index ast.Expr, index_
 			}
 			c.error('$type_str', pos)
 		}
-		if index is ast.PrefixExpr {
-			if index.op == .minus && index.right is ast.IntegerLiteral {
-				val := (index.right as ast.IntegerLiteral).val
-				if val.int() > 0 {
-					c.error('invalid index `-$val` (index must be non-negative)', index.pos)
-				}
+		if index is ast.IntegerLiteral {
+			if index.val.starts_with('-')  {
+				c.error('invalid index `$index.val` (index must be non-negative)', index.pos)
 			}
 		}
 		if index_type.has_flag(.optional) {

vlib/v/checker/tests/index_expr.out

@@ -16,7 +16,7 @@ vlib/v/checker/tests/index_expr.vv:7:8: error: invalid index `-1` (index must be
     5 |     a := [2]
     6 |     _ = a[a]
     7 |     _ = a[-1]
-      |           ^
+      |           ~~
     8 | }
     9 |
 vlib/v/checker/tests/index_expr.vv:12:7: error: type `int` does not support indexing
@@ -51,19 +51,19 @@ vlib/v/checker/tests/index_expr.vv:18:8: error: invalid index `-1` (index must b
    16 |     _ = a[a..]
    17 |     _ = a[..a]
    18 |     _ = a[-1..]
-      |           ^
+      |           ~~
    19 |     _ = a[..-1]
    20 |     _ = a[-1..-2]
 vlib/v/checker/tests/index_expr.vv:19:10: error: invalid index `-1` (index must be non-negative)
    17 |     _ = a[..a]
    18 |     _ = a[-1..]
    19 |     _ = a[..-1]
-      |             ^
+      |             ~~
    20 |     _ = a[-1..-2]
    21 | }
 vlib/v/checker/tests/index_expr.vv:20:8: error: invalid index `-1` (index must be non-negative)
    18 |     _ = a[-1..]
    19 |     _ = a[..-1]
    20 |     _ = a[-1..-2]
-      |           ^
+      |           ~~
    21 | }

vlib/v/checker/tests/overflow_int_err.out

@@ -1,8 +1,8 @@
-vlib/v/checker/tests/overflow_int_err.vv:4:8: error: overflow in implicit type `int`, use explicit type casting instead
+vlib/v/checker/tests/overflow_int_err.vv:4:7: error: overflow in implicit type `int`, use explicit type casting instead
     2 |     a := -2147483648
     3 |     b := 2147483647
     4 |     c := -2147483649
-      |           ~~~~~~~~~~
+      |          ~~~~~~~~~~~
     5 |     d := 2147483648
     6 |     println(a)
 vlib/v/checker/tests/overflow_int_err.vv:5:7: error: overflow in implicit type `int`, use explicit type casting instead

vlib/v/gen/cgen.v

@@ -2612,9 +2612,12 @@ fn (mut g Gen) expr(node ast.Expr) {
 				}
 				g.write('(${cast_label}(')
 				g.expr(node.expr)
-				if node.expr is ast.IntegerLiteral
-					&& node.typ in [table.u64_type, table.u32_type, table.u16_type] {
-					g.write('U')
+				if node.expr is ast.IntegerLiteral {
+					if node.typ in [table.u64_type, table.u32_type, table.u16_type] {
+						if !node.expr.val.starts_with('-') {
+							g.write('U')
+						}
+					}
 				}
 				g.write('))')
 			}
@@ -2691,6 +2694,9 @@ fn (mut g Gen) expr(node ast.Expr) {
 			if node.val.starts_with('0o') {
 				g.write('0')
 				g.write(node.val[2..])
+			} else if node.val.starts_with('-0o') {
+				g.write('-0')
+				g.write(node.val[3..])
 			} else {
 				g.write(node.val) // .int().str())
 			}

vlib/v/parser/parser.v

@@ -1726,17 +1726,23 @@ fn (mut p Parser) string_expr() ast.Expr {
 }
 
 fn (mut p Parser) parse_number_literal() ast.Expr {
+	mut pos := p.tok.position()
+	is_neg := p.tok.kind == .minus
+	if is_neg {
+		p.next()
+		pos = pos.extend(p.tok.position())
+	}
 	lit := p.tok.lit
-	pos := p.tok.position()
+	full_lit := if is_neg { '-' + lit } else { lit }
 	mut node := ast.Expr{}
 	if lit.index_any('.eE') >= 0 && lit[..2] !in ['0x', '0X', '0o', '0O', '0b', '0B'] {
 		node = ast.FloatLiteral{
-			val: lit
+			val: full_lit
 			pos: pos
 		}
 	} else {
 		node = ast.IntegerLiteral{
-			val: lit
+			val: full_lit
 			pos: pos
 		}
 	}

vlib/v/parser/pratt.v

@@ -74,10 +74,17 @@ pub fn (mut p Parser) expr(precedence int) ast.Expr {
 			}
 			p.next()
 		}
-		.minus, .amp, .mul, .not, .bit_not, .arrow {
+		.amp, .mul, .not, .bit_not, .arrow {
 			// -1, -a, !x, &x, ~x, <-a
 			node = p.prefix_expr()
 		}
+		.minus {
+			if p.peek_tok.kind == .number {
+				node = p.parse_number_literal()
+			} else {
+				node = p.prefix_expr()
+			}
+		}
 		.key_true, .key_false {
 			node = ast.BoolLiteral{
 				val: p.tok.kind == .key_true

vlib/v/parser/v_parser_test.v

@@ -175,6 +175,48 @@ fn test_parse_expr() {
 	}
 }
 
+fn test_num_literals() {
+	inputs := [
+		'a := -1',
+		'b := -12.e17'
+		'c := -12.'
+		'd := -a'
+	]
+	table := table.new_table()
+	mut scope := &ast.Scope{
+		start_pos: 0
+		parent: 0
+	}
+	mut rhs_types := []string{}
+	for input in inputs {
+		stmt := parser.parse_stmt(input, table, scope)
+		r := (stmt as ast.AssignStmt).right
+		match r[0] {
+			ast.IntegerLiteral {
+				rhs_types << 'int literal'
+			}
+			ast.FloatLiteral {
+				rhs_types << 'float literal'
+			}
+			ast.PrefixExpr {
+				rhs_types << 'prefix expression'
+			}
+			else {
+				rhs_types << 'something else'
+			}
+		}
+	}
+	mut rhs_type := rhs_types[0]
+	assert rhs_type == 'int literal'
+	rhs_type = rhs_types[1]
+	assert rhs_type == 'float literal'
+	rhs_type = rhs_types[2]
+	assert rhs_type == 'float literal'
+	rhs_type = rhs_types[3]
+	assert rhs_type == 'prefix expression'
+}
+
+
 /*
 table := &table.Table{}
 for s in text_expr {

vlib/v/tests/array_map_or_test.v

@@ -94,7 +94,7 @@ fn test_propagation() {
 		17
 	}
 	n := get_arr_el_direct(0) or {
-		int(-73)
+		-73
 	}
 	assert testvar1 == -34
 	assert testvar2 == 99