From 7fbe619f72b2f8ec672b50571609efa4b7ea61d5 Mon Sep 17 00:00:00 2001
From: Eric Willigers <keiravillekode@gmail.com>
Date: Mon, 10 Aug 2026 16:41:53 +1000
Subject: [PATCH] phone-number: return null on invalid input

Remove interface version check in bin/.test-in-docker
---
 bin/.test-in-docker                                      | 9 ++++++---
 .../practice/phone-number/.docs/instructions.append.md   | 6 ++++++
 2 files changed, 12 insertions(+), 3 deletions(-)
 create mode 100644 exercises/practice/phone-number/.docs/instructions.append.md

diff --git a/bin/.test-in-docker b/bin/.test-in-docker
index bb5c1433..9adbba67 100644
--- a/bin/.test-in-docker
+++ b/bin/.test-in-docker
@@ -18,12 +18,15 @@ for slug in $all_slugs; do
   # their solution.
   cp /tmp/solution/.meta/example.zig "/tmp/solution/${snake}.zig"
   bin/run.sh "${slug}" /tmp/solution /tmp/solution > /dev/null
-  solution_pattern=$(cat /tmp/solution/results.json | jq -r tostring | grep "{\"version\":2,\"status\":\"pass\"")
 
   errors=""
 
-  if [ -z "$solution_pattern" ]; then
-    errors="${errors}\n\nSolution is incorrect:\n$(cat /tmp/solution/results.json | jq -r '.message')"
+  if ! jq -e '.status == "pass"' /tmp/solution/results.json > /dev/null; then
+    # A compile error reports at the top level; failing tests report per test.
+    errors="${errors}\n\nSolution is incorrect:\n$(jq -r '
+      .message
+      // ([.tests[]? | select(.status != "pass") | "\(.name):\n\(.message // "no message")"] | join("\n\n"))
+    ' /tmp/solution/results.json)"
     local_exit_code=1;
   fi
 
diff --git a/exercises/practice/phone-number/.docs/instructions.append.md b/exercises/practice/phone-number/.docs/instructions.append.md
new file mode 100644
index 00000000..2bbe85a6
--- /dev/null
+++ b/exercises/practice/phone-number/.docs/instructions.append.md
@@ -0,0 +1,6 @@
+# Instructions append
+
+## Invalid numbers
+
+`clean` returns `?[10]u8`, an optional array of ten digits.
+Return `null` for a number that cannot be cleaned up.