From 100b3986b83b061745f6211f549ec337cbbb7d4d Mon Sep 17 00:00:00 2001
From: Alexander Medvednikov <alexander@medvednikov.com>
Date: Sat, 6 Jun 2020 12:28:03 +0200
Subject: [PATCH] parser: handle ! after CallExpr

---
 vlib/v/gen/str.v       | 2 ++
 vlib/v/parser/fn.v     | 9 +++++++--
 vlib/v/parser/parser.v | 7 ++++++-
 3 files changed, 15 insertions(+), 3 deletions(-)

diff --git a/vlib/v/gen/str.v b/vlib/v/gen/str.v
index c070c6b8e9..9890d7bdaa 100644
--- a/vlib/v/gen/str.v
+++ b/vlib/v/gen/str.v
@@ -96,6 +96,7 @@ string _STR_TMP(const char *fmt, ...) {
 	va_start(argptr, fmt);
 	vsprintf((char *)g_str_buf, fmt, argptr);
 	va_end(argptr);
+
 #ifdef DEBUG_ALLOC
 	//puts('_STR_TMP:');
 	//puts(g_str_buf);
@@ -103,6 +104,7 @@ string _STR_TMP(const char *fmt, ...) {
 	string res = tos(g_str_buf,  len);
 	res.is_lit = true;
 	return res;
+
 } // endof _STR_TMP
 
 ")
diff --git a/vlib/v/parser/fn.v b/vlib/v/parser/fn.v
index ece7aaaf94..8fe86d7b73 100644
--- a/vlib/v/parser/fn.v
+++ b/vlib/v/parser/fn.v
@@ -42,6 +42,10 @@ pub fn (mut p Parser) call_expr(language table.Language, mod string) ast.CallExp
 	args := p.call_args()
 	last_pos := p.tok.position()
 	p.check(.rpar)
+	// ! in mutable methods
+	if p.tok.kind == .not {
+		p.next()
+	}
 	pos := token.Position{
 		line_nr: first_pos.line_nr
 		pos: first_pos.pos
@@ -347,7 +351,7 @@ fn (mut p Parser) anon_fn() ast.AnonFn {
 	}
 }
 
-// fn decl
+// part of fn declaration
 fn (mut p Parser) fn_args() ([]table.Arg, bool) {
 	p.check(.lpar)
 	mut args := []table.Arg{}
@@ -463,7 +467,8 @@ fn (mut p Parser) check_fn_mutable_arguments(typ table.Type, pos token.Position)
 	sym := p.table.get_type_symbol(typ)
 	if sym.kind !in [.array, .struct_, .map, .placeholder] && !typ.is_ptr() {
 		p.error_with_pos('mutable arguments are only allowed for arrays, maps, and structs\n' +
-			'return values instead: `fn foo(mut n $sym.name) {` => `fn foo(n $sym.name) $sym.name {`', pos)
+			'return values instead: `fn foo(mut n $sym.name) {` => `fn foo(n $sym.name) $sym.name {`',
+			pos)
 	}
 }
 
diff --git a/vlib/v/parser/parser.v b/vlib/v/parser/parser.v
index 2ecb5da3f0..7331b994e0 100644
--- a/vlib/v/parser/parser.v
+++ b/vlib/v/parser/parser.v
@@ -891,7 +891,8 @@ pub fn (mut p Parser) name_expr() ast.Expr {
 	} else if p.peek_tok.kind == .lcbr && !p.inside_match && !p.inside_match_case && !p.inside_if &&
 		!p.inside_for {
 		return p.struct_init(false) // short_syntax: false
-	} else if p.peek_tok.kind == .dot && (p.tok.lit[0].is_capital() && !known_var && language == .v) {
+	} else if p.peek_tok.kind == .dot && (p.tok.lit[0].is_capital() && !known_var && language ==
+		.v) {
 		// `Color.green`
 		mut enum_name := p.check_name()
 		if mod != '' {
@@ -1000,6 +1001,7 @@ fn (mut p Parser) dot_expr(left ast.Expr) ast.Expr {
 		// }
 	}
 	// Method call
+	// TODO move to fn.v call_expr()
 	if p.tok.kind == .lpar {
 		p.next()
 		args := p.call_args()
@@ -1028,6 +1030,9 @@ fn (mut p Parser) dot_expr(left ast.Expr) ast.Expr {
 			or_stmts = p.parse_block_no_scope()
 			p.close_scope()
 		}
+		if p.tok.kind == .not {
+			p.next()
+		}
 		if p.tok.kind == .question {
 			// `foo()?`
 			p.next()