[PATCH v2 3/9] test: move dm-verity testdata generation to fixture

[Jonas Rebmann <jre@pengutronix.de>]

Simplify barebox integration test setup by moving logic away from
scripts/ and .github/.

Instead of generating testdata in separate scripts, they should be
implemented as testfs fixtures which are automatically ran as part of
the test suite.

Includes error handling and cleanup.

Signed-off-by: Jonas Rebmann <jre@pengutronix.de>
---
 scripts/generate_testfs.sh | 44 -----------------------------------
 test/py/test_dm.py         | 57 ++++++++++++++++++++++++++++++++++++++++++++--
 2 files changed, 55 insertions(+), 46 deletions(-)

diff --git a/scripts/generate_testfs.sh b/scripts/generate_testfs.sh
index e0a4013e05..d52772e6bf 100755
--- a/scripts/generate_testfs.sh
+++ b/scripts/generate_testfs.sh
@@ -31,47 +31,3 @@ generate_fit()
 if [ -f .github/testfs/${KBUILD_DEFCONFIG}-gzipped.its ]; then
 	generate_fit
 fi
-
-alias pad128k="dd if=/dev/zero bs=128k count=1 status=none"
-
-generate_dm_verity()
-{
-    work=$(mktemp -d)
-    cd ${work}
-
-    # Create two dummy files; use lots of padding to make sure that
-    # when we alter the contents of 'english' in root-bad, 'latin' is
-    # still be readable, as their contents wont (a) share the same
-    # hash block and (b) the block cache layer won't accedentally read
-    # the invalid block.
-
-    pad128k  >latin
-    echo -n "veritas vos liberabit" >>latin
-    pad128k >>latin
-
-    pad128k  >english
-    echo -n "truth will set you free" >>english
-    pad128k >>english
-
-    truncate -s 1M good.fat
-    mkfs.vfat good.fat
-    mcopy -i good.fat latin english ::
-
-    veritysetup format \
-		--root-hash-file=good.hash \
-		good.fat good.verity
-
-    sed 's/truth will set you free/LIAR LIAR PANTS ON FIRE/' \
-	<good.fat >bad.fat
-
-    cd -
-    cp \
-	${work}/good.fat \
-	${work}/good.verity \
-	${work}/good.hash \
-	${work}/bad.fat \
-	${KBUILD_OUTPUT}/testfs
-
-    rm -rf ${work}
-}
-generate_dm_verity
diff --git a/test/py/test_dm.py b/test/py/test_dm.py
index 8bdacf7b4e..adeb9cbe03 100644
--- a/test/py/test_dm.py
+++ b/test/py/test_dm.py
@@ -4,10 +4,63 @@ import re
 import pytest
 from .helper import of_get_property
 
+import os, subprocess, shutil
 
+def pad128k(f):
+    f.write(b"\0" * 128 * 1024)
 
-def test_dm_verity(barebox, testfs):
-    barebox.run_check("cd /mnt/9p/testfs")
+@pytest.fixture(scope="module")
+def dm_testdata(testfs):
+    path = os.path.join(testfs, "dm")
+    os.makedirs(path, exist_ok=True)
+    cwd = os.getcwd()
+    os.chdir(path)
+
+    with open("latin", "wb") as f:
+        pad128k(f)
+        f.write(b"veritas vos liberabit")
+        pad128k(f)
+
+    with open("english", "wb") as f:
+        pad128k(f)
+        f.write(b"truth will set you free")
+        pad128k(f)
+
+    try:
+        subprocess.run(["truncate", "-s", "1M", "good.fat"], check=True)
+        subprocess.run(["mkfs.vfat", "good.fat"], check=True)
+        subprocess.run(["mcopy", "-i", "good.fat", "latin", "english", "::"], check=True)
+
+        subprocess.run([
+            "veritysetup", "format",
+            "--root-hash-file=good.hash",
+            "good.fat", "good.verity"
+        ], check=True)
+    except FileNotFoundError as e:
+        os.chdir(cwd)
+        shutil.rmtree(path)
+        pytest.skip(f"missing dependency: {e}")
+
+    with open("good.fat", "rb") as f: data = f.read()
+    with open("bad.fat", "wb") as f:
+        f.write(data.replace(
+            b"truth will set you free",
+            b"LIAR LIAR PANTS ON FIRE"
+        ))
+
+    os.chdir(cwd)
+
+    yield path
+
+    shutil.rmtree(path)
+
+@pytest.fixture(autouse=True)
+def reset_pwd(barebox):
+    yield
+    barebox.run("cd")
+
+def test_dm_verity(barebox, dm_testdata):
+    barebox.run_check("cd /mnt/9p/testfs/dm")
 
     # Since commands run in a subshell, export the root hash in a
     # global, so that we can access it from subsequent commands

-- 
2.51.0.297.gca2559c1d6