From 0a3b09df75c78e66c69140a6bb75b8b5a81e9616 Mon Sep 17 00:00:00 2001
From: Tobias Happ <tobias.happ@gmx.de>
Date: Fri, 28 Oct 2022 19:57:03 +0200
Subject: [PATCH] tests: add fakedroid as flake app

---
 .github/workflows/fakedroid-odt.yml | 34 ++++++-------------------
 README.md                           | 39 +++++++++++++++++++++++++++++
 flake.nix                           |  5 ++++
 3 files changed, 51 insertions(+), 27 deletions(-)

diff --git a/.github/workflows/fakedroid-odt.yml b/.github/workflows/fakedroid-odt.yml
index 3c5522f..4a4ec90 100644
--- a/.github/workflows/fakedroid-odt.yml
+++ b/.github/workflows/fakedroid-odt.yml
@@ -19,28 +19,18 @@ jobs:
           name: nix-on-droid
           signingKey: "${{ secrets.CACHIX_SIGNING_KEY }}"
 
-      - name: Build fakedroid script
-        run: |
-          nix \
-            --log-format bar-with-logs \
-            --option keep-going true \
-            --show-trace \
-            build .#fakedroid \
-            --impure \
-            --out-link fakedroid
-
       - name: Initialize fakedroid for channel setup
-        run: ./fakedroid echo INIT
+        run: nix run --impure .#fakedroid -- echo INIT
 
       - name: Run tests
         run: |
-          ./fakedroid mkdir -p .cache/nix-on-droid-self-test
-          ./fakedroid touch .cache/nix-on-droid-self-test/confirmation-granted
-          ./fakedroid nix-on-droid on-device-test
+          nix run --impure .#fakedroid -- mkdir -p .cache/nix-on-droid-self-test
+          nix run --impure .#fakedroid -- touch .cache/nix-on-droid-self-test/confirmation-granted
+          nix run --impure .#fakedroid -- nix-on-droid on-device-test
 
       - name: Push to cachix
         if: always() && github.event_name != 'pull_request'
-        run: ./fakedroid nix-shell -p cachix --run 'nix --extra-experimental-features nix-command path-info --all | cachix push nix-on-droid'
+        run: nix run --impure .#fakedroid -- nix-shell -p cachix --run 'nix --extra-experimental-features nix-command path-info --all | cachix push nix-on-droid'
 
 
   fakedroid-flakes:
@@ -59,19 +49,9 @@ jobs:
           name: nix-on-droid
           signingKey: "${{ secrets.CACHIX_SIGNING_KEY }}"
 
-      - name: Build fakedroid script
-        run: |
-          nix \
-            --log-format bar-with-logs \
-            --option keep-going true \
-            --show-trace \
-            build .#fakedroid \
-            --impure \
-            --out-link fakedroid
-
       - name: Initialize fakedroid for flake setup
-        run: USE_FLAKE=1 ./fakedroid echo INIT
+        run: USE_FLAKE=1 nix run --impure .#fakedroid -- echo INIT
 
       - name: Push to cachix
         if: always() && github.event_name != 'pull_request'
-        run: ./fakedroid nix-shell -p cachix --run 'nix --extra-experimental-features nix-command path-info --all | cachix push nix-on-droid'
+        run: nix run --impure .#fakedroid -- nix-shell -p cachix --run 'nix --extra-experimental-features nix-command path-info --all | cachix push nix-on-droid'
diff --git a/README.md b/README.md
index 9ebe633..4510edb 100644
--- a/README.md
+++ b/README.md
@@ -206,6 +206,45 @@ Use `nix-on-droid switch --flake .#device` to build and activate your configurat
 Therefore, every evaluation of a flake configuration will be executed with `--impure` flag. (This behaviour will be
 dropped as soon as the default setup does not require it anymore.)
 
+## Emulate `nix-on-droid`-like environment with `fakedroid`
+
+For easier debugging and testing, there is a so-called `fakedroid` environment which
+emulates the on-device environment including proot as good as possible.
+
+You can enter this emulated environment with
+
+```sh
+nix run --impure ".#fakedroid"
+```
+
+This will install nix-on-droid with initial channel setup and save the state of
+this session in the `.fakedroid` directory in the project directory. To enter this
+environment with initial flake setup, set `USE_FLAKE=1` as environment variable.
+Channel and flake setups can co-exist in the `.fakedroid` state directory. To
+rebuild/re-test the bootstrap process, remove the `.fakedroid` directory.
+
+To only run a command in fakedroid and not enter an interactive shell, just call it
+with the command as arguments:
+
+```sh
+nix run --impure ".#fakedroid" -- ls -l
+```
+
+## Testing
+
+In the [./tests/on-device](./tests/on-device) directory, there is small set
+of [bats](https://github.com/bats-core/bats-core) tests that can be executed on the
+android device or run in the `fakedroid` environment.
+
+To run the tests (on device or in fakedroid), run
+
+```sh
+nix-on-droid on-device-test
+```
+
+**Note:** This currently requires a channel setup and should only be executed on
+clean installations.
+
 ## Tips
 
 * To grant the app access to the storage, use the toggle in the app settings
diff --git a/flake.nix b/flake.nix
index ccc30ea..311106d 100644
--- a/flake.nix
+++ b/flake.nix
@@ -53,6 +53,11 @@
           type = "app";
           program = "${self.packages.${system}.nix-on-droid}/bin/nix-on-droid";
         };
+
+        fakedroid = {
+          type = "app";
+          program = toString self.packages.${system}.fakedroid;
+        };
       });
 
       checks = forEachSystem (system: {