From 8c8c3f7cd062c5bc637237f35ada3b06e4f2cda0 Mon Sep 17 00:00:00 2001
From: Frank <frank@dankware>
Date: Tue, 25 Aug 2026 16:18:01 -0700
Subject: [PATCH] Enable focused tests as repository pre-commit hook

---
 .githooks/pre-commit                |  6 ++++++
 docs/Architecture/Testing Policy.md | 17 ++++++++++++-----
 scripts/test-changed.sh             |  3 +++
 tests/changed_tests.bats            |  3 +++
 4 files changed, 24 insertions(+), 5 deletions(-)
 create mode 100755 .githooks/pre-commit

diff --git a/.githooks/pre-commit b/.githooks/pre-commit
new file mode 100755
index 0000000..f8a941d
--- /dev/null
+++ b/.githooks/pre-commit
@@ -0,0 +1,6 @@
+#!/usr/bin/env bash
+# Repository pre-commit hook: run only tests selected by staged paths.
+set -euo pipefail
+
+REPO_ROOT="$(git rev-parse --show-toplevel)"
+exec "$REPO_ROOT/scripts/test-changed.sh"
diff --git a/docs/Architecture/Testing Policy.md b/docs/Architecture/Testing Policy.md
index 9b34e01..5ce7826 100644
--- a/docs/Architecture/Testing Policy.md	
+++ b/docs/Architecture/Testing Policy.md	
@@ -22,11 +22,18 @@ For normal commits, use the focused wrapper:
 ```
 
 It reads staged paths with `git diff --cached` and runs only the mapped Bats
-files. Use `--list` to inspect the selection without running tests, or
-`--paths FILE ...` to preview a mapping. Shared test infrastructure and
-unmapped paths fail closed rather than silently skipping coverage. Run the
-full suite with `./tests/run.sh` when changing shared test helpers, the test
-runner, or when focused coverage is not sufficient.
+files. The tracked `.githooks/pre-commit` hook invokes this wrapper. Enable the
+repository hook path once per checkout:
+
+```bash
+git config core.hooksPath .githooks
+```
+
+Use `--list` to inspect the selection without running tests, or `--paths FILE
+...` to preview a mapping. Shared test infrastructure and unmapped paths fail
+closed rather than silently skipping coverage. Run the full suite with
+`./tests/run.sh` when changing shared test helpers, the test runner, or when
+focused coverage is not sufficient.
 
 ## Red-Green
 
diff --git a/scripts/test-changed.sh b/scripts/test-changed.sh
index 31406a0..c2bbd23 100755
--- a/scripts/test-changed.sh
+++ b/scripts/test-changed.sh
@@ -76,6 +76,9 @@ for path in "${CHANGED[@]}"; do
         tests/helpers.bash|tests/run.sh)
             die "$path is shared test infrastructure; run ./tests/run.sh explicitly"
             ;;
+        .githooks/*)
+            add_test tests/changed_tests.bats
+            ;;
         dankserver/compose.yaml|dankclaw/compose.yaml)
             add_test tests/compose_validity.bats
             add_test tests/env_consistency.bats
diff --git a/tests/changed_tests.bats b/tests/changed_tests.bats
index 0fc31e7..031618f 100644
--- a/tests/changed_tests.bats
+++ b/tests/changed_tests.bats
@@ -6,6 +6,9 @@ load helpers
 
 @test "changed-test wrapper is executable and uses staged diff by default" {
     [ -x "$REPO_ROOT/scripts/test-changed.sh" ]
+    [ -x "$REPO_ROOT/.githooks/pre-commit" ]
+    run grep -F 'scripts/test-changed.sh' "$REPO_ROOT/.githooks/pre-commit"
+    [ "$status" -eq 0 ]
     run grep -F 'git diff --cached' "$REPO_ROOT/scripts/test-changed.sh"
     [ "$status" -eq 0 ]
 }