build: add support for conflicting dependencies (MR 2146)

This adds support for the depends="!conflict ..." syntax for explicitly
marking another package as conflicting with the current one.

Fixes: #2085

pmb/build/_package.py

@@ -130,6 +130,9 @@ def build_depends(args, apkbuild, arch, strict):
     if "no_depends" in args and args.no_depends:
         pmb.helpers.repo.update(args, arch)
         for depend in depends:
+            # Ignore conflicting dependencies
+            if depend.startswith("!"):
+                continue
             # Check if binary package is missing
             if not pmb.parse.apkindex.package(args, depend, arch, False):
                 raise RuntimeError("Missing binary package for dependency '" +
@@ -147,6 +150,8 @@ def build_depends(args, apkbuild, arch, strict):
     else:
         # Build the dependencies
         for depend in depends:
+            if depend.startswith("!"):
+                continue
             if package(args, depend, arch, strict=strict):
                 depends_built += [depend]
         logging.verbose(pkgname + ": build dependencies: done, built: " +

pmb/chroot/apk.py

@@ -97,6 +97,10 @@ def install_is_necessary(args, build, arch, package, packages_installed):
     :returns: True if the package needs to be installed/updated,
               False otherwise.
     """
+    # For packages to be removed we can do the test immediately
+    if package.startswith("!"):
+        return package[1:] in packages_installed
+
     # User may have disabled buiding packages during "pmbootstrap install"
     build_disabled = False
     if args.action == "install" and not args.build_pkgs_on_install:

pmb/parse/apkindex.py

@@ -81,8 +81,6 @@ def parse_next_block(path, lines, start):
                 values = ret[key].split(" ")
                 ret[key] = []
                 for value in values:
-                    if value.startswith("!"):
-                        continue
                     for operator in [">", "=", "<", "~"]:
                         if operator in value:
                             value = value.split(operator)[0]

pmb/parse/depends.py

@@ -116,7 +116,8 @@ def recurse(args, pkgnames, suffix="native"):
                    has multiple providers, we look at the installed packages in
                    the chroot to make a decision (see package_provider()).
     :returns: list of pkgnames: consists of the initial pkgnames plus all
-              depends
+              depends. Dependencies explicitly marked as conflicting are
+              prefixed with !.
     """
     logging.debug(f"({suffix}) calculate depends of {', '.join(pkgnames)} "
                   "(pmbootstrap -v for details)")
@@ -131,6 +132,10 @@ def recurse(args, pkgnames, suffix="native"):
         if pkgname_depend in ret:
             continue
 
+        # Check if the dependency is explicitly marked as conflicting
+        is_conflict = pkgname_depend.startswith("!")
+        pkgname_depend = pkgname_depend.lstrip("!")
+
         # Get depends and pkgname from aports
         pkgnames_install = list(ret) + todo
         package = package_from_aports(args, pkgname_depend)
@@ -147,18 +152,23 @@ def recurse(args, pkgnames, suffix="native"):
                                f"Required by '{source}'. See: "
                                "https://postmarketos.org/depends")
 
-        # Append to todo/ret (unless it is a duplicate)
+        # Determine pkgname
         pkgname = package["pkgname"]
+        if is_conflict:
+            pkgname = f"!{pkgname}"
+
+        # Append to todo/ret (unless it is a duplicate)
         if pkgname in ret:
             logging.verbose(f"{pkgname}: already found")
         else:
-            depends = package["depends"]
-            logging.verbose(f"{pkgname}: depends on: {','.join(depends)}")
-            if depends:
-                todo += depends
-                for dep in depends:
-                    if dep not in required_by:
-                        required_by[dep] = set()
-                    required_by[dep].add(pkgname_depend)
+            if not is_conflict:
+                depends = package["depends"]
+                logging.verbose(f"{pkgname}: depends on: {','.join(depends)}")
+                if depends:
+                    todo += depends
+                    for dep in depends:
+                        if dep not in required_by:
+                            required_by[dep] = set()
+                        required_by[dep].add(pkgname_depend)
             ret.append(pkgname)
     return ret

test/test_apk.py

@@ -0,0 +1,32 @@
+# Copyright 2021 Oliver Smith
+# SPDX-License-Identifier: GPL-3.0-or-later
+import pytest
+import sys
+
+import pmb_test  # noqa
+import pmb.chroot.apk
+
+
+@pytest.fixture
+def args(tmpdir, request):
+    import pmb.parse
+    sys.argv = ["pmbootstrap.py", "init"]
+    args = pmb.parse.arguments()
+    args.log = args.work + "/log_testsuite.txt"
+    pmb.helpers.logging.init(args)
+    request.addfinalizer(pmb.helpers.logging.logfd.close)
+    return args
+
+
+def test_install_is_necessary(args):
+    # osk-sdl not installed, nothing to do
+    ret = pmb.chroot.apk.install_is_necessary(args, False, "aarch64",
+                                              "!osk-sdl",
+                                              {"unl0kr": {"unl0kr": {}}})
+    assert not ret
+
+    # osk-sdl installed, (un)install necessary
+    ret = pmb.chroot.apk.install_is_necessary(args, False, "aarch64",
+                                              "!osk-sdl",
+                                              {"osk-sdl": {"osk-sdl": {}}})
+    assert ret

test/test_build_package.py

@@ -140,16 +140,18 @@ def test_get_depends(monkeypatch):
 def test_build_depends(args, monkeypatch):
     # Shortcut and fake apkbuild
     func = pmb.build._package.build_depends
-    apkbuild = {"pkgname": "test", "depends": ["a"], "makedepends": ["b"],
-                "checkdepends": [], "subpackages": {"d": None}, "options": []}
+    apkbuild = {"pkgname": "test", "depends": ["a", "!c"],
+                "makedepends": ["b"], "checkdepends": [],
+                "subpackages": {"d": None}, "options": []}
 
     # No depends built (first makedepends + depends, then only makedepends)
     monkeypatch.setattr(pmb.build._package, "package", return_none)
-    assert func(args, apkbuild, "armhf", True) == (["a", "b"], [])
+    assert func(args, apkbuild, "armhf", True) == (["!c", "a", "b"], [])
 
     # All depends built (makedepends only)
     monkeypatch.setattr(pmb.build._package, "package", return_string)
-    assert func(args, apkbuild, "armhf", False) == (["a", "b"], ["a", "b"])
+    assert func(args, apkbuild, "armhf", False) == (["!c", "a", "b"],
+                                                    ["a", "b"])
 
 
 def test_build_depends_no_binary_error(args, monkeypatch):

test/test_parse_apkindex.py

@@ -115,6 +115,34 @@ def test_parse_next_block_virtual():
     assert start == [31]
 
 
+def test_parse_next_block_conflict():
+    """
+    Test parsing a package that specifies a conflicting dependency from an
+    APKINDEX.
+    """
+    # Read the file
+    func = pmb.parse.apkindex.parse_next_block
+    path = pmb.config.pmb_src + "/test/testdata/apkindex/conflict"
+    with open(path, "r", encoding="utf-8") as handle:
+        lines = handle.readlines()
+
+    # First block
+    start = [0]
+    block = {'arch': 'x86_64',
+             'depends': ['!conflict', 'so:libc.musl-x86_64.so.1'],
+             'origin': 'hello-world',
+             'pkgname': 'hello-world',
+             'provides': ['cmd:hello-world'],
+             'timestamp': '1500000000',
+             'version': '2-r0'}
+    assert func(path, lines, start) == block
+    assert start == [20]
+
+    # No more blocks
+    assert func(path, lines, start) is None
+    assert start == [20]
+
+
 def test_parse_add_block(args):
     func = pmb.parse.apkindex.parse_add_block
     multiple_providers = False

test/test_parse_depends.py

@@ -146,7 +146,8 @@ def test_recurse(args, monkeypatch):
     depends = {
         "test": ["libtest", "so:libtest.so.1"],
         "libtest": ["libtest_depend"],
-        "libtest_depend": [],
+        "libtest_depend": ["!libtest_conflict"],
+        "libtest_conflict": [],
         "so:libtest.so.1": ["libtest_depend"],
     }
 
@@ -158,5 +159,6 @@ def test_recurse(args, monkeypatch):
     # Run
     func = pmb.parse.depends.recurse
     pkgnames = ["test", "so:libtest.so.1"]
-    result = ["test", "so:libtest.so.1", "libtest", "libtest_depend"]
+    result = ["test", "so:libtest.so.1", "libtest", "libtest_depend",
+              "!libtest_conflict"]
     assert func(args, pkgnames) == result

test/testdata/apkindex/conflict

@@ -0,0 +1,20 @@
+C:Q1XaZzCVZ9mvH8djPyEb5aUYhG3r4=
+P:hello-world
+V:2-r0
+A:x86_64
+S:2897
+I:20480
+T:hello world program to be built in the testsuite
+U:https://en.wikipedia.org/wiki/%22Hello,_World!%22_program
+L:MIT
+o:hello-world
+t:1500000000
+c:
+D:!conflict so:libc.musl-x86_64.so.1
+p:cmd:hello-world
+F:usr
+F:usr/bin
+R:hello-world
+a:0:0:755
+Z:Q1ZjTpsnMchSsSwEPB1cTjihYuJvo=
+