From 1f3428f282736a82ebcb3303ab68ecfd2ac3215d Mon Sep 17 00:00:00 2001
From: Alexander Medvednikov <alexander@medvednikov.com>
Date: Thu, 26 Mar 2020 10:27:46 +0100
Subject: [PATCH] cgen: basic assert

---
 vlib/v/checker/checker.v |  3 +++
 vlib/v/gen/cgen.v        | 17 +++++++++++++----
 vlib/v/gen/cheaders.v    |  2 ++
 3 files changed, 18 insertions(+), 4 deletions(-)

diff --git a/vlib/v/checker/checker.v b/vlib/v/checker/checker.v
index e1e679e3e8..fff400da8c 100644
--- a/vlib/v/checker/checker.v
+++ b/vlib/v/checker/checker.v
@@ -527,6 +527,9 @@ pub fn (c mut Checker) array_init(array_init mut ast.ArrayInit) table.Type {
 fn (c mut Checker) stmt(node ast.Stmt) {
 	// c.expected_type = table.void_type
 	match mut node {
+		ast.AssertStmt {
+			c.expr(it.expr)
+		}
 		ast.AssignStmt {
 			c.assign_stmt(mut it)
 			c.expected_type = table.void_type
diff --git a/vlib/v/gen/cgen.v b/vlib/v/gen/cgen.v
index dd6d4930db..1cb9f7267c 100644
--- a/vlib/v/gen/cgen.v
+++ b/vlib/v/gen/cgen.v
@@ -268,12 +268,21 @@ fn (g mut Gen) stmt(node ast.Stmt) {
 	// println('cgen.stmt()')
 	// g.writeln('//// stmt start')
 	match node {
-		ast.AssignStmt {
-			g.gen_assign_stmt(it)
-		}
 		ast.AssertStmt {
 			g.writeln('// assert')
-			// TODO
+			g.write('if (!(')
+			g.expr(it.expr)
+			g.writeln(')) {')
+			g.writeln('g_test_fails++;')
+			g.writeln('puts("FAILED assertion");')
+			g.writeln('puts("function: $g.fn_decl.name");')
+			g.writeln('} else {')
+			g.writeln('g_test_oks++;')
+			g.writeln('puts("OK $g.fn_decl.name");')
+			g.writeln('}')
+		}
+		ast.AssignStmt {
+			g.gen_assign_stmt(it)
 		}
 		ast.Attr {
 			g.writeln('//[$it.name]')
diff --git a/vlib/v/gen/cheaders.v b/vlib/v/gen/cheaders.v
index 94deb93e4b..34961516a0 100644
--- a/vlib/v/gen/cheaders.v
+++ b/vlib/v/gen/cheaders.v
@@ -186,6 +186,8 @@ extern wchar_t **_wenviron;
 
 //================================== GLOBALS =================================*/
 byte g_str_buf[1024];
+int g_test_fails = 0;
+int g_test_oks = 0;
 int load_so(byteptr);
 void reload_so();
 void _vinit();