Merge ~dbungert/curtin:integration-run-bm-debug into curtin:master

[Dan Bungert]

integration: add run_bm(..., debug=True) helper

The debug argument for run_bm allows for running curtin outside of the
integration test itself, but with all the setup being done for you by
the integration test. This means that custom tweaks can be done to the
curtin code before running, setting breakpoints, etc.

[Server Team CI bot (server-team-bot)]

PASSED: Continuous integration, rev:ab4f99f00f809e7ef899e6f91c53783ef47c9ab4
https://jenkins.canonical.com/server-team/job/curtin-ci/225/
Executed test runs:
    SUCCESS: https://jenkins.canonical.com/server-team/job/curtin-ci/nodes=metal-amd64/225/
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    SUCCESS: https://jenkins.canonical.com/server-team/job/curtin-ci/nodes=metal-ppc64el/225/
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review: Approve (continuous-integration)

[Server Team CI bot (server-team-bot)]

PASSED: Continuous integration, rev:942bb97d2fdcb463d00812e26bafe60ac1190850
https://jenkins.canonical.com/server-team/job/curtin-ci/236/
Executed test runs:
    SUCCESS: https://jenkins.canonical.com/server-team/job/curtin-ci/nodes=metal-amd64/236/
    SUCCESS: https://jenkins.canonical.com/server-team/job/curtin-ci/nodes=metal-arm64/236/
    SUCCESS: https://jenkins.canonical.com/server-team/job/curtin-ci/nodes=metal-ppc64el/236/
    SUCCESS: https://jenkins.canonical.com/server-team/job/curtin-ci/nodes=metal-s390x/236/

Click here to trigger a rebuild:
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review: Approve (continuous-integration)

[Chris Peterson (cpete)]

Very nice! One question about the kwargs bit but I looked through all the calls to run_bm and it doesn't look like it's really used anyways.

review: Approve

Unmerged commits

942bb97... by Dan Bungert on 2023-05-16

integration: add run_bm(..., debug=True) helper

The debug argument for run_bm allows for running curtin outside of the
integration test itself, but with all the setup being done for you by
the integration test. This means that custom tweaks can be done to the
curtin code before running, setting breakpoints, etc.

diff --git a/tests/integration/test_block_meta.py b/tests/integration/test_block_meta.py
index 2fc7c7d..1867f63 100644
--- a/tests/integration/test_block_meta.py
+++ b/tests/integration/test_block_meta.py
@@ -10,6 +10,7 @@ from pathlib import Path
 import re
 import sys
 from typing import Optional
+import tempfile
 from unittest import skipIf
 import yaml
 
@@ -267,7 +268,37 @@ class TestBlockMeta(IntegrationTestCase):
             '-c', config_path, 'block-meta', '--testmode', 'custom',
             *args,
             ]
-        util.subp(cmd, env=cmd_env, **kwargs)
+
+        # Set debug=True to halt the integration test and run curtin manually,
+        # with the integration tests having setup the environment for you.
+        # To see the script name run with "pytest-3 -s", or look at fp.name.
+        if not kwargs.pop('debug', False):
+            util.subp(cmd, env=cmd_env, **kwargs)
+            return
+
+        env = cmd_env.copy()
+        env.update(PYTHONPATH=os.getcwd())
+        import pprint
+        pp = pprint.PrettyPrinter(indent=4)
+        code = '''\
+#!/usr/bin/python3
+import subprocess
+cmd = {cmd}
+env = {env}
+subprocess.run(cmd, env=env)
+'''.format(cmd=pp.pformat(cmd), env=pp.pformat(env))
+
+        opts = dict(mode='w', delete=False, suffix='.py')
+        with tempfile.NamedTemporaryFile(**opts) as fp:
+            fp.write(code)
+        try:
+            os.chmod(fp.name, 0o700)
+            print('\nThe integration test is paused.')
+            print('Use script {} to run curtin manually.'.format(fp.name))
+            import pdb
+            pdb.set_trace()
+        finally:
+            os.unlink(fp.name)
 
     def _test_default_offsets(self, ptable, version, sector_size=512):
         psize = 40 << 20