std.debug.assert: remove special case for test builds

Previously, std.debug.assert would `@panic` in test builds,
if the assertion failed. Now, it's always `unreachable`.

This makes release mode test builds more accurately test
the actual code that will be run.

However this requires tests to call `std.testing.expect`
rather than `std.debug.assert` to make sure output is correct.

Here is the explanation of when to use either one, copied from
the assert doc comments:

Inside a test block, it is best to use the `std.testing` module
rather than assert, because assert may not detect a test failure
in ReleaseFast and ReleaseSafe mode. Outside of a test block, assert
is the correct function to use.

closes #1304

1 files changed, 2 insertions, 2 deletions

diff --git a/std/special/init-lib/src/main.zig b/std/special/init-lib/src/main.zig
index 27fdeb2030..747bb08573 100644
--- a/std/special/init-lib/src/main.zig
+++ b/std/special/init-lib/src/main.zig
@@ -1,10 +1,10 @@
 const std = @import("std");
-const assertOrPanic = std.debug.assertOrPanic;
+const testing = std.testing;
 
 export fn add(a: i32, b: i32) i32 {
     return a + b;
 }
 
 test "basic add functionality" {
-    assertOrPanic(add(3, 7) == 10);
+    testing.expect(add(3, 7) == 10);
 }