From f1fdafcdffcea58f3b1f9737b261125425aaf93b Mon Sep 17 00:00:00 2001
From: Delyan Angelov <delian66@gmail.com>
Date: Sun, 12 Jul 2020 22:44:38 +0300
Subject: [PATCH] pref: add -check-syntax for just parsing files, without
 checking them

---
 vlib/v/builder/c.v  | 3 +++
 vlib/v/builder/cc.v | 6 ++++++
 vlib/v/pref/pref.v  | 4 ++++
 3 files changed, 13 insertions(+)

diff --git a/vlib/v/builder/c.v b/vlib/v/builder/c.v
index 34f57fddd2..f9698fd8df 100644
--- a/vlib/v/builder/c.v
+++ b/vlib/v/builder/c.v
@@ -13,6 +13,9 @@ pub fn (mut b Builder) gen_c(v_files []string) string {
 	t1 := time.ticks()
 	parse_time := t1 - t0
 	b.info('PARSE: ${parse_time}ms')
+	if b.pref.only_check_syntax {
+		return ''
+	}
 	//
 	b.generic_struct_insts_to_concrete()
 	b.checker.check_files(b.parsed_files)
diff --git a/vlib/v/builder/cc.v b/vlib/v/builder/cc.v
index 910f42c059..e83f35966d 100644
--- a/vlib/v/builder/cc.v
+++ b/vlib/v/builder/cc.v
@@ -76,6 +76,12 @@ fn (mut v Builder) cc() {
 	if v.pref.is_verbose {
 		println('builder.cc() pref.out_name="$v.pref.out_name"')
 	}
+	if v.pref.only_check_syntax {
+		if v.pref.is_verbose {
+			println('builder.cc returning early, since pref.only_check_syntax is true')
+		}
+		return
+	}
 	v.build_thirdparty_obj_files()
 	vexe := pref.vexe_path()
 	vdir := os.dir(vexe)
diff --git a/vlib/v/pref/pref.v b/vlib/v/pref/pref.v
index e3a31708b3..0e4ea9aa47 100644
--- a/vlib/v/pref/pref.v
+++ b/vlib/v/pref/pref.v
@@ -115,6 +115,7 @@ pub mut:
 	is_parallel         bool
 	error_limit         int
 	is_vweb             bool // skip _ var warning in templates
+	only_check_syntax   bool // when true, just parse the files, then stop, before running checker
 }
 
 pub fn parse_args(args []string) (&Preferences, string) {
@@ -126,6 +127,9 @@ pub fn parse_args(args []string) (&Preferences, string) {
 		arg := args[i]
 		current_args := args[i..]
 		match arg {
+			'-check-syntax' {
+				res.only_check_syntax = true
+			}
 			'-v' {
 				res.is_verbose = true
 			}