lib.distros.Distro.install_*(): Add install_deps

The install methods of Distro inconsistently resolve dependencies or don't
depending on the descendant's implementation. Pin that more unambigously by
adding a new parameter install_deps, defaulting to True, to the following
methods of lib.Distro:

  _install_local_files()
  _install_urls()
  _install_urls_and_names()
  install()

The implementations in lib.distros.* make use of the new
lib.pm.*.install_packages() method introduced by the previous commit.

Add a unit test directory per Distro descendant.

Assisted-by: unsloth/Qwen3.8-27B-GGUF:Q4_K_M with pi.dev v1.4.0
Signed-off-by: Jan Lindemann <jan@janware.com>

test/unit/python/jw/pkg/lib/distros/debian/Makefile

@@ -0,0 +1,7 @@
+TOPDIR = ../../../../../../../..
+
+include $(TOPDIR)/make/proj.mk
+include $(JWBDIR)/make/py-run.mk
+
+all:
+test: run

test/unit/python/jw/pkg/lib/distros/debian/test.py

@@ -0,0 +1,127 @@
+from __future__ import annotations
+
+import asyncio
+
+from typing import override
+
+from jw.pkg.lib.distros.debian.Distro import Distro as DebianDistro
+from jw.pkg.lib.ec.Local import Local
+from jw.pkg.lib.Result import Result
+
+class DispatchLocal(Local):
+    """A canned execution context that answers dpkg queries and
+    the apt simulation"""
+
+    def __init__(
+        self,
+        files: dict[str, str],
+        installed: dict[str, str],
+        simulate: str,
+    ) -> None:
+        super().__init__('local')
+        self.files = files
+        self.installed = installed
+        self.simulate = simulate
+        self.cmds: list[list[str]] = []
+
+    @override
+    async def _run(
+        self,
+        cmd: list[str],
+        wd: str | None,
+        verbose: bool,
+        cmd_input: bytes | None,
+        mod_env: dict[str, str] | None,
+        interactive: bool,
+        log_prefix: str,
+    ) -> Result:
+        self.cmds.append(cmd)
+        if '-I' in cmd:
+            return Result(stdout = self.files.get(cmd[-1], '').encode(), status = 0)
+        if cmd[0].endswith('dpkg-query'):
+            name = cmd[-1]
+            return Result(
+                stdout = self.installed.get(name, '').encode(),
+                status = 0 if name in self.installed else 1,
+            )
+        if '/usr/bin/apt-get' in cmd and '-s' in cmd:
+            return Result(stdout = self.simulate.encode(), status = 0)
+        return Result(stdout = b'', status = 0)
+
+def dpkg_args(cmd: list[str]) -> list[str]:
+    """The dpkg command without the sudo prefix and its options"""
+    return cmd[cmd.index('/usr/bin/dpkg'):]
+
+# -- A mixed transaction runs two installs, the upgrades first: the
+# distro installs local files with force, which keeps the reinstall
+# semantics for already-installed versions
+cl = DispatchLocal(
+    files = {
+        '/a/jw-base-run-1.0.0-42.deb': 'Package: jw-base\nVersion: 1.0.0-42',
+        '/a/jw-base-run-1.0.0-41.deb': 'Package: jw-base\nVersion: 1.0.0-41',
+    },
+    installed = {'jw-base': 'jw-base|||||1.0.0-42'},
+    simulate = 'Inst jw-base [1.0.0-41]\n',
+)
+d = DebianDistro(cl, id = 'debian')
+asyncio.run(
+    d._install_local_files(
+        ['/a/jw-base-run-1.0.0-42.deb', '/a/jw-base-run-1.0.0-41.deb'],
+        False,
+        install_deps = False,
+    )
+)
+installs = [dpkg_args(cmd) for cmd in cl.cmds if '-i' in cmd]
+assert installs == [
+    ['/usr/bin/dpkg', '-i', '/a/jw-base-run-1.0.0-41.deb'],
+    [
+        '/usr/bin/dpkg',
+        '-i',
+        '--force-reinstall',
+        '/a/jw-base-run-1.0.0-42.deb',
+    ],
+]
+
+# -- only_update raises on files whose package is not installed
+cl = DispatchLocal(
+    files = {
+        '/a/jw-base-run-1.0.0-42.deb': 'Package: jw-base\nVersion: 1.0.0-42',
+        '/a/jw-foo-run-1.0.0-42.deb': 'Package: jw-foo\nVersion: 1.0.0-42',
+    },
+    installed = {'jw-base': 'jw-base|||||1.0.0-42'},
+    simulate = '',
+)
+d = DebianDistro(cl, id = 'debian')
+try:
+    asyncio.run(
+        d._install_local_files(
+            ['/a/jw-base-run-1.0.0-42.deb', '/a/jw-foo-run-1.0.0-42.deb'],
+            True,
+            install_deps = False,
+        )
+    )
+except Exception as e:
+    assert '/a/jw-foo-run-1.0.0-42.deb' in str(e)
+else:
+    raise AssertionError('expected an exception')
+assert not [cmd for cmd in cl.cmds if '-i' in cmd]
+
+# -- deps routes local files through the package manager
+cl = DispatchLocal(
+    files = {'/a/jw-base-run-1.0.0-42.deb': 'Package: jw-base\nVersion: 1.0.0-42'},
+    installed = {'jw-base': 'jw-base|||||1.0.0-42'},
+    simulate = '',
+)
+d = DebianDistro(cl, id = 'debian')
+asyncio.run(
+    d._install_local_files(['/a/jw-base-run-1.0.0-42.deb'], False, install_deps = True)
+)
+pm_cmds = [cmd for cmd in cl.cmds if '/usr/bin/apt-get' in cmd]
+assert len(pm_cmds) == 1
+args = pm_cmds[0][pm_cmds[0].index('/usr/bin/apt-get'):]
+assert 'install' in args
+assert '--no-install-recommends' in args
+assert args[-1] == '/a/jw-base-run-1.0.0-42.deb'
+assert not [cmd for cmd in cl.cmds if '-i' in cmd]
+
+print('All debian distro tests passed')