docs: point at the renamed canary repo, disambiguate the local clone

.gitignore

@@ -10,7 +10,14 @@
 *.swo
 *~
 
-# Test directories
+# Local scratch space for test infrastructure (see tests/README.md).
+# Everything under tests/ is committed EXCEPT tests/local/, which is where
+# throwaway clones of real lecture repos go. Keeping them under a directory
+# that can never be a repo name avoids shadowing one.
+tests/local/
+
+# Legacy scratch patterns — kept so existing local clones stay ignored.
+# Prefer tests/local/ for anything new.
 test-*/
 examples-*/
 

PLAN.md

@@ -22,7 +22,7 @@ The core infrastructure is complete, hardened, and in production:
 |---|---|---|
 | `lecture-dp` | Full chain: `restore-jupyter-cache`, `build-lectures`, `build-jupyter-cache`, `publish-gh-pages` | `@v0.8.0` |
 | `lecture-python.myst` | `preview-netlify` (ci.yml) | `@v0.8.0` |
-| `test-lecture-python-intro` | Full chain (test harness) | `@v0.6.0` |
+| `test-actions-lecture-intro` | Full chain (canary — see #100 stage 2) | `@v0.6.0` ⚠️ stale, dormant |
 
 Consumer/migration tracking lives in [QuantEcon/meta#321](https://github.com/QuantEcon/meta/issues/321); the preview-unification rollout is planned in [QuantEcon/meta#327](https://github.com/QuantEcon/meta/issues/327).
 

TESTING.md

@@ -38,9 +38,13 @@ Fixtures are salted with `run_id`-`run_attempt` so cache keys are unique per run
 
 ## Local Test Fixtures
 
-### `test-lecture-python-intro/` (git-ignored)
+### `tests/local/` (git-ignored)
 
-A local clone of `lecture-python-intro` used for testing workflows locally. This directory is excluded from version control via the `.gitignore` pattern `test-*/`.
+Scratch space for local clones of real lecture repos, used to test workflows on your own machine against something larger than the committed fixture. Ignored via `tests/local/` in `.gitignore`, so it exists only in your working tree — never committed, and read by no workflow. See [tests/README.md](tests/README.md) for the wider layout.
+
+> **Not to be confused with [`QuantEcon/test-actions-lecture-intro`](https://github.com/QuantEcon/test-actions-lecture-intro)**, the canary repo that runs the actions in real CI (#100 stage 2). This is a throwaway directory; that is a live repo.
+>
+> Local clones used to be documented at the repo root as `test-lecture-python-intro/`, one character away from the canary's old name — close enough that the two were repeatedly confused. A path under `tests/local/` cannot collide with a repo name. The old `test-*/` ignore pattern is retained, so existing local clones stay ignored where they are.
 
 **Purpose:**
 - Test container builds locally
@@ -49,8 +53,8 @@ A local clone of `lecture-python-intro` used for testing workflows locally. This
 
 **Setup:**
 ```bash
-# Clone test fixture (from actions repo root)
-git clone https://github.com/QuantEcon/lecture-python-intro.git test-lecture-python-intro
+# from the repo root
+git clone https://github.com/QuantEcon/lecture-python-intro.git tests/local/lecture-python-intro
 ```
 
 **Usage with local scripts:**
@@ -110,7 +114,7 @@ docker run --rm ghcr.io/quantecon/quantecon:latest pdflatex --version
 
 ## Phase 2: Test Repository Workflow
 
-### 2.1 Update test-lecture-python-intro
+### 2.1 Update test-actions-lecture-intro
 
 Create container-based workflow:
 
@@ -248,7 +252,7 @@ Pick a test repository or create a fork:
 2. Monitor for 1 week
 3. Collect metrics (build times, success rate)
 
-Complete testing with test-lecture-python-intro, validate all metrics.
+Complete testing with `QuantEcon/test-actions-lecture-intro`, validate all metrics.
 
 ### Stage 2: CPU Lecture Repositories
 

tests/README.md

@@ -0,0 +1,34 @@
+# Tests
+
+Home for this repo's test infrastructure. Today it holds the local scratch area; it exists as a named place so future test tooling has somewhere obvious to land instead of accumulating at the repo root.
+
+See [TESTING.md](../TESTING.md) for the strategy and how to run things.
+
+## What lives where
+
+Test assets are currently spread across the repo, each next to what it tests. This table is the map — nothing has been moved.
+
+| Location | What | Committed? |
+|---|---|---|
+| `.github/workflows/test-actions.yml` | The PR harness — 14 jobs exercising the cache, environment and build actions via `uses: ./` local paths (#100 stage 1) | yes |
+| `.github/fixtures/mini-lectures/` | Fixture for the harness: a two-page book with a real executed code cell, so builds populate a genuine `_build/.jupyter_cache` | yes |
+| `containers/quantecon/tests/` | Container smoke tests and their minimal book | yes |
+| `tests/local/` | Throwaway clones of real lecture repos, for manual testing | **no** — git-ignored |
+| [`QuantEcon/test-actions-lecture-intro`](https://github.com/QuantEcon/test-actions-lecture-intro) | The canary repo (#100 stage 2). Pinned `@v0`, so it exercises `publish-gh-pages` and `preview-netlify` — neither is testable in this repo | separate repo |
+
+## `tests/local/`
+
+Git-ignored. Clone real lecture repos here when you want to test against something larger than the committed fixture:
+
+```bash
+# from the repo root
+git clone https://github.com/QuantEcon/lecture-python-intro.git tests/local/lecture-python-intro
+```
+
+Nothing in CI reads this directory — it exists only in your working tree.
+
+Put local clones **here** rather than at the repo root. A root-level `test-lecture-python-intro/` shadowed the canary repo's old name closely enough that the two were repeatedly confused, including in the PR that wrote this file. A path under `tests/local/` cannot collide with a repo name.
+
+## Adding test infrastructure
+
+Fixtures that a workflow consumes should stay next to that workflow (`.github/fixtures/`, `containers/*/tests/`) so the `paths:` filters keep working. Use `tests/` for tooling that spans more than one of them — a shared harness runner, cross-action integration scripts, or fixture-generation tooling.