Add analyze_bcpf.py script to help manage bootclasspath_fragments

The analyze_bcpf.py script can be used by bootclasspath_fragment owners
to help setup their fragment and also to debug issues that arise during
use.

It is run by specifying the name of the bootclasspath_fragment module
in the --bcpf option. If specified the --apex and --sdk options will
allow the tool to produce more helpful messages.

The script currently:
* Builds out/soong/hiddenapi/hiddenapi-stub-flags.txt and checks any
  inconsistencies between those flags and the flags generated for the
  bootclasspath_fragment.

* Builds out/soong/hiddenapi/hiddenapi-flags.csv and checks any
  inconsistencies between those flags and the flags generated for the
  bootclasspath_fragment. It will describe the changes that need to
  be made in order to fix any inconsistencies in the flags.

Bug: 202154151
Test: m analyze_bcpf && analyze_bcpf --bcpf art-bootclasspath-fragment
      atest --host analyze_bcpf_test
Change-Id: I824fd9d527d246dfe56725c073d89a0b0e72d25a
diff --git a/scripts/hiddenapi/analyze_bcpf_test.py b/scripts/hiddenapi/analyze_bcpf_test.py
new file mode 100644
index 0000000..8e34671
--- /dev/null
+++ b/scripts/hiddenapi/analyze_bcpf_test.py
@@ -0,0 +1,331 @@
+#!/usr/bin/env python
+#
+# Copyright (C) 2022 The Android Open Source Project
+#
+# Licensed under the Apache License, Version 2.0 (the 'License');
+# you may not use this file except in compliance with the License.
+# You may obtain a copy of the License at
+#
+#      http://www.apache.org/licenses/LICENSE-2.0
+#
+# Unless required by applicable law or agreed to in writing, software
+# distributed under the License is distributed on an 'AS IS' BASIS,
+# WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+# See the License for the specific language governing permissions and
+# limitations under the License.
+"""Unit tests for analyzing bootclasspath_fragment modules."""
+import os.path
+import shutil
+import tempfile
+import unittest
+import unittest.mock
+
+import analyze_bcpf as ab
+
+_FRAMEWORK_HIDDENAPI = "frameworks/base/boot/hiddenapi"
+_MAX_TARGET_O = f"{_FRAMEWORK_HIDDENAPI}/hiddenapi-max-target-o.txt"
+_MAX_TARGET_P = f"{_FRAMEWORK_HIDDENAPI}/hiddenapi-max-target-p.txt"
+_MAX_TARGET_Q = f"{_FRAMEWORK_HIDDENAPI}/hiddenapi-max-target-q.txt"
+_MAX_TARGET_R = f"{_FRAMEWORK_HIDDENAPI}/hiddenapi-max-target-r-loprio.txt"
+
+_MULTI_LINE_COMMENT = """
+Lorem ipsum dolor sit amet, consectetur adipiscing elit. Ut arcu justo,
+bibendum eu malesuada vel, fringilla in odio. Etiam gravida ultricies sem
+tincidunt luctus.""".replace("\n", " ").strip()
+
+
+class FakeBuildOperation(ab.BuildOperation):
+
+    def __init__(self, lines, return_code):
+        ab.BuildOperation.__init__(self, None)
+        self._lines = lines
+        self.returncode = return_code
+
+    def lines(self):
+        return iter(self._lines)
+
+    def wait(self, *args, **kwargs):
+        return
+
+
+class TestAnalyzeBcpf(unittest.TestCase):
+
+    def setUp(self):
+        # Create a temporary directory
+        self.test_dir = tempfile.mkdtemp()
+
+    def tearDown(self):
+        # Remove the directory after the test
+        shutil.rmtree(self.test_dir)
+
+    @staticmethod
+    def write_abs_file(abs_path, contents):
+        os.makedirs(os.path.dirname(abs_path), exist_ok=True)
+        with open(abs_path, "w", encoding="utf8") as f:
+            print(contents.removeprefix("\n"), file=f, end="")
+
+    def populate_fs(self, fs):
+        for path, contents in fs.items():
+            abs_path = os.path.join(self.test_dir, path)
+            self.write_abs_file(abs_path, contents)
+
+    def create_analyzer_for_test(self,
+                                 fs=None,
+                                 bcpf="bcpf",
+                                 apex="apex",
+                                 sdk="sdk"):
+        if fs:
+            self.populate_fs(fs)
+
+        top_dir = self.test_dir
+        out_dir = os.path.join(self.test_dir, "out")
+        product_out_dir = "out/product"
+
+        bcpf_dir = f"{bcpf}-dir"
+        modules = {bcpf: {"path": [bcpf_dir]}}
+        module_info = ab.ModuleInfo(modules)
+
+        analyzer = ab.BcpfAnalyzer(
+            top_dir=top_dir,
+            out_dir=out_dir,
+            product_out_dir=product_out_dir,
+            bcpf=bcpf,
+            apex=apex,
+            sdk=sdk,
+            module_info=module_info,
+        )
+        analyzer.load_all_flags()
+        return analyzer
+
+    def test_reformat_report_text(self):
+        lines = """
+99. An item in a numbered list
+that traverses multiple lines.
+
+   An indented example
+   that should not be reformatted.
+"""
+        reformatted = ab.BcpfAnalyzer.reformat_report_test(lines)
+        self.assertEqual(
+            """
+99. An item in a numbered list that traverses multiple lines.
+
+   An indented example
+   that should not be reformatted.
+""", reformatted)
+
+    def test_build_flags(self):
+        lines = """
+ERROR: Hidden API flags are inconsistent:
+< out/soong/.intermediates/bcpf-dir/bcpf-dir/filtered-flags.csv
+> out/soong/hiddenapi/hiddenapi-flags.csv
+
+< Lacme/test/Class;-><init>()V,blocked
+> Lacme/test/Class;-><init>()V,max-target-o
+
+< Lacme/test/Other;->getThing()Z,blocked
+> Lacme/test/Other;->getThing()Z,max-target-p
+
+< Lacme/test/Widget;-><init()V,blocked
+> Lacme/test/Widget;-><init()V,max-target-q
+
+< Lacme/test/Gadget;->NAME:Ljava/lang/String;,blocked
+> Lacme/test/Gadget;->NAME:Ljava/lang/String;,lo-prio,max-target-r
+16:37:32 ninja failed with: exit status 1
+""".strip().splitlines()
+        operation = FakeBuildOperation(lines=lines, return_code=1)
+
+        fs = {
+            _MAX_TARGET_O:
+                """
+Lacme/items/Magnet;->size:I
+Lacme/test/Class;-><init>()V
+""",
+            _MAX_TARGET_P:
+                """
+Lacme/items/Rocket;->size:I
+Lacme/test/Other;->getThing()Z
+""",
+            _MAX_TARGET_Q:
+                """
+Lacme/items/Rock;->size:I
+Lacme/test/Widget;-><init()V
+""",
+            _MAX_TARGET_R:
+                """
+Lacme/items/Lever;->size:I
+Lacme/test/Gadget;->NAME:Ljava/lang/String;
+""",
+            "bcpf-dir/hiddenapi/hiddenapi-max-target-p.txt":
+                """
+Lacme/old/Class;->getWidget()Lacme/test/Widget;
+""",
+            "out/soong/.intermediates/bcpf-dir/bcpf/all-flags.csv":
+                """
+Lacme/test/Gadget;->NAME:Ljava/lang/String;,blocked
+Lacme/test/Widget;-><init()V,blocked
+Lacme/test/Class;-><init>()V,blocked
+Lacme/test/Other;->getThing()Z,blocked
+""",
+        }
+
+        analyzer = self.create_analyzer_for_test(fs)
+
+        # Override the build_file_read_output() method to just return a fake
+        # build operation.
+        analyzer.build_file_read_output = unittest.mock.Mock(
+            return_value=operation)
+
+        # Override the run_command() method to do nothing.
+        analyzer.run_command = unittest.mock.Mock()
+
+        result = ab.Result()
+
+        analyzer.build_monolithic_flags(result)
+        expected_diffs = {
+            "Lacme/test/Gadget;->NAME:Ljava/lang/String;":
+                (["blocked"], ["lo-prio", "max-target-r"]),
+            "Lacme/test/Widget;-><init()V": (["blocked"], ["max-target-q"]),
+            "Lacme/test/Class;-><init>()V": (["blocked"], ["max-target-o"]),
+            "Lacme/test/Other;->getThing()Z": (["blocked"], ["max-target-p"])
+        }
+        self.assertEqual(expected_diffs, result.diffs, msg="flag differences")
+
+        expected_property_changes = [
+            ab.HiddenApiPropertyChange(
+                property_name="max_target_o_low_priority",
+                values=["hiddenapi/hiddenapi-max-target-o-low-priority.txt"],
+                property_comment=""),
+            ab.HiddenApiPropertyChange(
+                property_name="max_target_p",
+                values=["hiddenapi/hiddenapi-max-target-p.txt"],
+                property_comment=""),
+            ab.HiddenApiPropertyChange(
+                property_name="max_target_q",
+                values=["hiddenapi/hiddenapi-max-target-q.txt"],
+                property_comment=""),
+            ab.HiddenApiPropertyChange(
+                property_name="max_target_r_low_priority",
+                values=["hiddenapi/hiddenapi-max-target-r-low-priority.txt"],
+                property_comment=""),
+        ]
+        self.assertEqual(
+            expected_property_changes,
+            result.property_changes,
+            msg="property changes")
+
+        expected_file_changes = [
+            ab.FileChange(
+                path="bcpf-dir/hiddenapi/"
+                "hiddenapi-max-target-o-low-priority.txt",
+                description="""Add the following entries:
+            Lacme/test/Class;-><init>()V
+""",
+            ),
+            ab.FileChange(
+                path="bcpf-dir/hiddenapi/hiddenapi-max-target-p.txt",
+                description="""Add the following entries:
+            Lacme/test/Other;->getThing()Z
+""",
+            ),
+            ab.FileChange(
+                path="bcpf-dir/hiddenapi/hiddenapi-max-target-q.txt",
+                description="""Add the following entries:
+            Lacme/test/Widget;-><init()V
+"""),
+            ab.FileChange(
+                path="bcpf-dir/hiddenapi/"
+                "hiddenapi-max-target-r-low-priority.txt",
+                description="""Add the following entries:
+            Lacme/test/Gadget;->NAME:Ljava/lang/String;
+"""),
+            ab.FileChange(
+                path="frameworks/base/boot/hiddenapi/"
+                "hiddenapi-max-target-o.txt",
+                description="""Remove the following entries:
+            Lacme/test/Class;-><init>()V
+"""),
+            ab.FileChange(
+                path="frameworks/base/boot/hiddenapi/"
+                "hiddenapi-max-target-p.txt",
+                description="""Remove the following entries:
+            Lacme/test/Other;->getThing()Z
+"""),
+            ab.FileChange(
+                path="frameworks/base/boot/hiddenapi/"
+                "hiddenapi-max-target-q.txt",
+                description="""Remove the following entries:
+            Lacme/test/Widget;-><init()V
+"""),
+            ab.FileChange(
+                path="frameworks/base/boot/hiddenapi/"
+                "hiddenapi-max-target-r-loprio.txt",
+                description="""Remove the following entries:
+            Lacme/test/Gadget;->NAME:Ljava/lang/String;
+""")
+        ]
+        result.file_changes.sort()
+        self.assertEqual(
+            expected_file_changes, result.file_changes, msg="file_changes")
+
+
+class TestHiddenApiPropertyChange(unittest.TestCase):
+
+    def setUp(self):
+        # Create a temporary directory
+        self.test_dir = tempfile.mkdtemp()
+
+    def tearDown(self):
+        # Remove the directory after the test
+        shutil.rmtree(self.test_dir)
+
+    def check_change_snippet(self, change, expected):
+        snippet = change.snippet("        ")
+        self.assertEqual(expected, snippet)
+
+    def test_change_property_with_value_no_comment(self):
+        change = ab.HiddenApiPropertyChange(
+            property_name="split_packages",
+            values=["android.provider"],
+        )
+
+        self.check_change_snippet(
+            change, """
+        split_packages: [
+            "android.provider",
+        ],
+""")
+
+    def test_change_property_with_value_and_comment(self):
+        change = ab.HiddenApiPropertyChange(
+            property_name="split_packages",
+            values=["android.provider"],
+            property_comment=_MULTI_LINE_COMMENT,
+        )
+
+        self.check_change_snippet(
+            change, """
+        // Lorem ipsum dolor sit amet, consectetur adipiscing elit. Ut arcu
+        // justo, bibendum eu malesuada vel, fringilla in odio. Etiam gravida
+        // ultricies sem tincidunt luctus.
+        split_packages: [
+            "android.provider",
+        ],
+""")
+
+    def test_change_without_value_or_empty_comment(self):
+        change = ab.HiddenApiPropertyChange(
+            property_name="split_packages",
+            values=[],
+            property_comment="Single line comment.",
+        )
+
+        self.check_change_snippet(
+            change, """
+        // Single line comment.
+        split_packages: [],
+""")
+
+
+if __name__ == "__main__":
+    unittest.main(verbosity=3)