From 6a0a2da05c4b4da57ce15a51a3d267962ceb47ee Mon Sep 17 00:00:00 2001
From: Delyan Angelov <delian66@gmail.com>
Date: Wed, 3 Jun 2020 10:16:08 +0300
Subject: [PATCH] cgen: support `$if test { ... }`

---
 vlib/v/gen/cgen.v                            |  6 ++++++
 vlib/v/tests/comptime_if_test_support_test.v | 10 ++++++++++
 2 files changed, 16 insertions(+)
 create mode 100644 vlib/v/tests/comptime_if_test_support_test.v

diff --git a/vlib/v/gen/cgen.v b/vlib/v/gen/cgen.v
index 2da086a9ca..721d6adf73 100644
--- a/vlib/v/gen/cgen.v
+++ b/vlib/v/gen/cgen.v
@@ -267,6 +267,9 @@ pub fn (mut g Gen) init() {
 	if g.pref.is_debug || 'debug' in g.pref.compile_defines {
 		g.comptime_defines.writeln('#define _VDEBUG (1)')
 	}
+	if g.pref.is_test || 'test' in g.pref.compile_defines {
+		g.comptime_defines.writeln('#define _VTEST (1)')
+	}
 	if g.pref.is_livemain || g.pref.is_liveshared {
 		g.generate_hotcode_reloading_declarations()
 	}
@@ -3451,6 +3454,9 @@ fn (mut g Gen) comp_if_to_ifdef(name string, is_comptime_optional bool) string {
 		'debug' {
 			return '_VDEBUG'
 		}
+		'test' {
+			return '_VTEST'
+		}
 		'glibc' {
 			return '__GLIBC__'
 		}
diff --git a/vlib/v/tests/comptime_if_test_support_test.v b/vlib/v/tests/comptime_if_test_support_test.v
new file mode 100644
index 0000000000..5eaf2bbd7e
--- /dev/null
+++ b/vlib/v/tests/comptime_if_test_support_test.v
@@ -0,0 +1,10 @@
+fn test_comptime_if_test() {
+	mut i := 0
+	$if test {
+		i++
+	}
+	$if !test {
+		i--
+	}
+	assert i == 1
+}