From 481f103dc99c4128fc8dcce18b122f0d6872a46d Mon Sep 17 00:00:00 2001
From: Delyan Angelov <delian66@gmail.com>
Date: Wed, 27 May 2020 12:00:08 +0300
Subject: [PATCH] checker: make an error using non `pub` fns from other modules

---
 vlib/builtin/string.v    | 5 +----
 vlib/v/checker/checker.v | 5 ++---
 vlib/v/util/errors.v     | 2 +-
 3 files changed, 4 insertions(+), 8 deletions(-)

diff --git a/vlib/builtin/string.v b/vlib/builtin/string.v
index 65af029ca6..a4aa301953 100644
--- a/vlib/builtin/string.v
+++ b/vlib/builtin/string.v
@@ -940,10 +940,7 @@ pub fn (s string) trim_suffix(str string) string {
 	return s
 }
 
-// fn print_cur_thread() {
-// //C.printf("tid = %08x \n", pthread_self());
-// }
-fn compare_strings(a, b &string) int {
+pub fn compare_strings(a, b &string) int {
 	if a.lt(b) {
 		return -1
 	}
diff --git a/vlib/v/checker/checker.v b/vlib/v/checker/checker.v
index 22d5bb2dfa..524af0d416 100644
--- a/vlib/v/checker/checker.v
+++ b/vlib/v/checker/checker.v
@@ -911,9 +911,8 @@ pub fn (mut c Checker) call_fn(mut call_expr ast.CallExpr) table.Type {
 				call_expr.pos)
 		}
 	}
-	if !f.is_pub && f.language == .v && !c.is_builtin_mod && !c.pref.is_test && f.mod != c.mod &&
-		f.name != '' && f.mod != '' {
-		c.warn('function `$f.name` is private. curmod=$c.mod fmod=$f.mod', call_expr.pos)
+	if !f.is_pub && f.language == .v && f.name.len > 0 && f.mod.len > 0 && f.mod != c.mod {
+		c.error('function `$f.name` is private. curmod=$c.mod fmod=$f.mod', call_expr.pos)
 	}
 	call_expr.return_type = f.return_type
 	if f.return_type == table.void_type && f.ctdefine.len > 0 && f.ctdefine !in c.pref.compile_defines {
diff --git a/vlib/v/util/errors.v b/vlib/v/util/errors.v
index 3b34f1cf67..bc0778761a 100644
--- a/vlib/v/util/errors.v
+++ b/vlib/v/util/errors.v
@@ -174,7 +174,7 @@ pub fn color_compare_files(diff_cmd, file1, file2 string) string {
     return ''
 }
 
-fn color_compare_strings(diff_cmd string, expected string, found string) string {
+pub fn color_compare_strings(diff_cmd string, expected string, found string) string {
 	cdir := os.cache_dir()
 	ctime := time.sys_mono_now()
 	e_file := os.join_path(cdir, '${ctime}.expected.txt')