From 258ef17401f558941646685fb47ab24a236271b6 Mon Sep 17 00:00:00 2001
From: =?UTF-8?q?K=C5=8Dan?= <koan.bot@atoomic.org>
Date: Sat, 21 Feb 2026 08:45:43 -0700
Subject: [PATCH] fix: Assert plugin always throws on defined values (GH #300)
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Template::Monad::Assert::AUTOLOAD was passing $stash instead of $this
to dotop(), causing it to look up the item in the root stash rather
than in the actual hash/list being asserted on.

For example, [% foo.assert.bar %] would look for 'bar' in the stash
root (where it doesn't exist) instead of in foo, always throwing
"undefined value for bar" even when foo.bar is defined.

Added 6 tests covering defined-value pass-through for hashes, nested
hashes, arrays, and direct stash variable access.

Fixes #300

Co-Authored-By: Kōan <noreply@anthropic.com>
---
 lib/Template/Plugin/Assert.pm |  2 +-
 t/assert.t                    | 52 +++++++++++++++++++++++++++++++++--
 2 files changed, 51 insertions(+), 3 deletions(-)

diff --git a/lib/Template/Plugin/Assert.pm b/lib/Template/Plugin/Assert.pm
index df34dfa3c..1e1c3a199 100644
--- a/lib/Template/Plugin/Assert.pm
+++ b/lib/Template/Plugin/Assert.pm
@@ -84,7 +84,7 @@ sub AUTOLOAD {
     $item =~ s/.*:://;
     return if $item eq 'DESTROY';
 
-    my $value = $stash->dotop($stash, $item, \@args);
+    my $value = $stash->dotop($this, $item, \@args);
 
     if (! defined $value) {
         die $EXCEPTION->new( assert => "undefined value for $item" );
diff --git a/t/assert.t b/t/assert.t
index 0aa7c48cd..ddd957d69 100644
--- a/t/assert.t
+++ b/t/assert.t
@@ -40,12 +40,15 @@ sub nil {
 
 package main;
 
-my $vars = { 
+my $vars = {
     object => Template::Test::Object->new,
     hash   => { foo => 10, bar => undef },
     list   => [ undef ],
     subref => sub { return undef },
     nothing => undef,
+    nested => { name => 'hello', deep => { value => 42 } },
+    items  => [ 10, 20, 30 ],
+    name   => 'world',
 };
 
 test_expect(\*DATA, undef, $vars);
@@ -105,11 +108,56 @@ assert error - undefined value for first
 -- expect --
 assert error - undefined value for nothing
 
--- test -- 
+-- test --
 [% USE assert;
    TRY; assert.subref; CATCH; error; END;
 %]
 -- expect --
 assert error - undefined value for subref
 
+#------------------------------------------------------------------------
+# GH #300: assert should pass through defined values without error
+#------------------------------------------------------------------------
+
+-- test --
+[% USE assert;
+   hash.assert.foo;
+%]
+-- expect --
+10
+
+-- test --
+[% USE assert;
+   nested.assert.name;
+%]
+-- expect --
+hello
+
+-- test --
+[% USE assert;
+   nested.assert.deep.value;
+%]
+-- expect --
+42
+
+-- test --
+[% USE assert;
+   items.assert.size;
+%]
+-- expect --
+3
+
+-- test --
+[% USE assert;
+   items.assert.first;
+%]
+-- expect --
+10
+
+-- test --
+[% USE assert;
+   assert.name;
+%]
+-- expect --
+world