Add a real parser for the version scripts.

Bionic's version scripts are unfortunately complicated enough that the
naive processing I was doing before is not going to be sufficient.
Add a real parser/generator with a bunch of tests to fix this.

Test: cc/test_gen_stub_libs.py && make ndk
Change-Id: I0f73b41ade1e6cf4e31bf70ba43a743429ce770b
diff --git a/cc/test_gen_stub_libs.py b/cc/test_gen_stub_libs.py
new file mode 100755
index 0000000..8436a48
--- /dev/null
+++ b/cc/test_gen_stub_libs.py
@@ -0,0 +1,440 @@
+#!/usr/bin/env python
+#
+# Copyright (C) 2016 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.
+#
+"""Tests for gen_stub_libs.py."""
+import cStringIO
+import textwrap
+import unittest
+
+import gen_stub_libs as gsl
+
+
+# pylint: disable=missing-docstring
+
+
+class TagsTest(unittest.TestCase):
+    def test_get_tags_no_tags(self):
+        self.assertEqual([], gsl.get_tags(''))
+        self.assertEqual([], gsl.get_tags('foo bar baz'))
+
+    def test_get_tags(self):
+        self.assertEqual(['foo', 'bar'], gsl.get_tags('# foo bar'))
+        self.assertEqual(['bar', 'baz'], gsl.get_tags('foo # bar baz'))
+
+    def test_get_tag_value(self):
+        self.assertEqual('bar', gsl.get_tag_value('foo=bar'))
+        self.assertEqual('bar=baz', gsl.get_tag_value('foo=bar=baz'))
+        with self.assertRaises(ValueError):
+            gsl.get_tag_value('foo')
+
+
+class PrivateVersionTest(unittest.TestCase):
+    def test_version_is_private(self):
+        self.assertFalse(gsl.version_is_private('foo'))
+        self.assertFalse(gsl.version_is_private('PRIVATE'))
+        self.assertFalse(gsl.version_is_private('PLATFORM'))
+        self.assertFalse(gsl.version_is_private('foo_private'))
+        self.assertFalse(gsl.version_is_private('foo_platform'))
+        self.assertFalse(gsl.version_is_private('foo_PRIVATE_'))
+        self.assertFalse(gsl.version_is_private('foo_PLATFORM_'))
+
+        self.assertTrue(gsl.version_is_private('foo_PRIVATE'))
+        self.assertTrue(gsl.version_is_private('foo_PLATFORM'))
+
+
+class SymbolPresenceTest(unittest.TestCase):
+    def test_symbol_in_arch(self):
+        self.assertTrue(gsl.symbol_in_arch([], 'arm'))
+        self.assertTrue(gsl.symbol_in_arch(['arm'], 'arm'))
+
+        self.assertFalse(gsl.symbol_in_arch(['x86'], 'arm'))
+
+    def test_symbol_in_api(self):
+        self.assertTrue(gsl.symbol_in_api([], 'arm', 9))
+        self.assertTrue(gsl.symbol_in_api(['introduced=9'], 'arm', 9))
+        self.assertTrue(gsl.symbol_in_api(['introduced=9'], 'arm', 14))
+        self.assertTrue(gsl.symbol_in_api(['introduced-arm=9'], 'arm', 14))
+        self.assertTrue(gsl.symbol_in_api(['introduced-arm=9'], 'arm', 14))
+        self.assertTrue(gsl.symbol_in_api(['introduced-x86=14'], 'arm', 9))
+        self.assertTrue(gsl.symbol_in_api(
+            ['introduced-arm=9', 'introduced-x86=21'], 'arm', 14))
+        self.assertTrue(gsl.symbol_in_api(
+            ['introduced=9', 'introduced-x86=21'], 'arm', 14))
+        self.assertTrue(gsl.symbol_in_api(
+            ['introduced=21', 'introduced-arm=9'], 'arm', 14))
+
+        self.assertFalse(gsl.symbol_in_api(['introduced=14'], 'arm', 9))
+        self.assertFalse(gsl.symbol_in_api(['introduced-arm=14'], 'arm', 9))
+        self.assertFalse(gsl.symbol_in_api(['future'], 'arm', 9))
+        self.assertFalse(gsl.symbol_in_api(
+            ['introduced=9', 'future'], 'arm', 14))
+        self.assertFalse(gsl.symbol_in_api(
+            ['introduced-arm=9', 'future'], 'arm', 14))
+        self.assertFalse(gsl.symbol_in_api(
+            ['introduced-arm=21', 'introduced-x86=9'], 'arm', 14))
+        self.assertFalse(gsl.symbol_in_api(
+            ['introduced=9', 'introduced-arm=21'], 'arm', 14))
+        self.assertFalse(gsl.symbol_in_api(
+            ['introduced=21', 'introduced-x86=9'], 'arm', 14))
+
+        # Interesting edge case: this symbol should be omitted from the
+        # library, but this call should still return true because none of the
+        # tags indiciate that it's not present in this API level.
+        self.assertTrue(gsl.symbol_in_api(['x86'], 'arm', 9))
+
+    def test_verioned_in_api(self):
+        self.assertTrue(gsl.symbol_versioned_in_api([], 9))
+        self.assertTrue(gsl.symbol_versioned_in_api(['versioned=9'], 9))
+        self.assertTrue(gsl.symbol_versioned_in_api(['versioned=9'], 14))
+
+        self.assertFalse(gsl.symbol_versioned_in_api(['versioned=14'], 9))
+
+
+class OmitVersionTest(unittest.TestCase):
+    def test_omit_private(self):
+        self.assertFalse(gsl.should_omit_version('foo', [], 'arm', 9))
+
+        self.assertTrue(gsl.should_omit_version('foo_PRIVATE', [], 'arm', 9))
+        self.assertTrue(gsl.should_omit_version('foo_PLATFORM', [], 'arm', 9))
+
+    def test_omit_arch(self):
+        self.assertFalse(gsl.should_omit_version('foo', [], 'arm', 9))
+        self.assertFalse(gsl.should_omit_version('foo', ['arm'], 'arm', 9))
+
+        self.assertTrue(gsl.should_omit_version('foo', ['x86'], 'arm', 9))
+
+    def test_omit_api(self):
+        self.assertFalse(gsl.should_omit_version('foo', [], 'arm', 9))
+        self.assertFalse(
+            gsl.should_omit_version('foo', ['introduced=9'], 'arm', 9))
+
+        self.assertTrue(
+            gsl.should_omit_version('foo', ['introduced=14'], 'arm', 9))
+
+
+class SymbolFileParseTest(unittest.TestCase):
+    def test_next_line(self):
+        input_file = cStringIO.StringIO(textwrap.dedent("""\
+            foo
+
+            bar
+            # baz
+            qux
+        """))
+        parser = gsl.SymbolFileParser(input_file)
+        self.assertIsNone(parser.current_line)
+
+        self.assertEqual('foo', parser.next_line().strip())
+        self.assertEqual('foo', parser.current_line.strip())
+
+        self.assertEqual('bar', parser.next_line().strip())
+        self.assertEqual('bar', parser.current_line.strip())
+
+        self.assertEqual('qux', parser.next_line().strip())
+        self.assertEqual('qux', parser.current_line.strip())
+
+        self.assertEqual('', parser.next_line())
+        self.assertEqual('', parser.current_line)
+
+    def test_parse_version(self):
+        input_file = cStringIO.StringIO(textwrap.dedent("""\
+            VERSION_1 { # foo bar
+                baz;
+                qux; # woodly doodly
+            };
+
+            VERSION_2 {
+            } VERSION_1; # asdf
+        """))
+        parser = gsl.SymbolFileParser(input_file)
+
+        parser.next_line()
+        version = parser.parse_version()
+        self.assertEqual('VERSION_1', version.name)
+        self.assertIsNone(version.base)
+        self.assertEqual(['foo', 'bar'], version.tags)
+
+        expected_symbols = [
+            gsl.Symbol('baz', []),
+            gsl.Symbol('qux', ['woodly', 'doodly']),
+        ]
+        self.assertEqual(expected_symbols, version.symbols)
+
+        parser.next_line()
+        version = parser.parse_version()
+        self.assertEqual('VERSION_2', version.name)
+        self.assertEqual('VERSION_1', version.base)
+        self.assertEqual([], version.tags)
+
+    def test_parse_version_eof(self):
+        input_file = cStringIO.StringIO(textwrap.dedent("""\
+            VERSION_1 {
+        """))
+        parser = gsl.SymbolFileParser(input_file)
+        parser.next_line()
+        with self.assertRaises(gsl.ParseError):
+            parser.parse_version()
+
+    def test_unknown_scope_label(self):
+        input_file = cStringIO.StringIO(textwrap.dedent("""\
+            VERSION_1 {
+                foo:
+            }
+        """))
+        parser = gsl.SymbolFileParser(input_file)
+        parser.next_line()
+        with self.assertRaises(gsl.ParseError):
+            parser.parse_version()
+
+    def test_parse_symbol(self):
+        input_file = cStringIO.StringIO(textwrap.dedent("""\
+            foo;
+            bar; # baz qux
+        """))
+        parser = gsl.SymbolFileParser(input_file)
+
+        parser.next_line()
+        symbol = parser.parse_symbol()
+        self.assertEqual('foo', symbol.name)
+        self.assertEqual([], symbol.tags)
+
+        parser.next_line()
+        symbol = parser.parse_symbol()
+        self.assertEqual('bar', symbol.name)
+        self.assertEqual(['baz', 'qux'], symbol.tags)
+
+    def test_wildcard_symbol_global(self):
+        input_file = cStringIO.StringIO(textwrap.dedent("""\
+            VERSION_1 {
+                *;
+            };
+        """))
+        parser = gsl.SymbolFileParser(input_file)
+        parser.next_line()
+        with self.assertRaises(gsl.ParseError):
+            parser.parse_version()
+
+    def test_wildcard_symbol_local(self):
+        input_file = cStringIO.StringIO(textwrap.dedent("""\
+            VERSION_1 {
+                local:
+                    *;
+            };
+        """))
+        parser = gsl.SymbolFileParser(input_file)
+        parser.next_line()
+        version = parser.parse_version()
+        self.assertEqual([], version.symbols)
+
+    def test_missing_semicolon(self):
+        input_file = cStringIO.StringIO(textwrap.dedent("""\
+            VERSION_1 {
+                foo
+            };
+        """))
+        parser = gsl.SymbolFileParser(input_file)
+        parser.next_line()
+        with self.assertRaises(gsl.ParseError):
+            parser.parse_version()
+
+    def test_parse_fails_invalid_input(self):
+        with self.assertRaises(gsl.ParseError):
+            input_file = cStringIO.StringIO('foo')
+            parser = gsl.SymbolFileParser(input_file)
+            parser.parse()
+
+    def test_parse(self):
+        input_file = cStringIO.StringIO(textwrap.dedent("""\
+            VERSION_1 {
+                local:
+                    hidden1;
+                global:
+                    foo;
+                    bar; # baz
+            };
+
+            VERSION_2 { # wasd
+                # Implicit global scope.
+                    woodly;
+                    doodly; # asdf
+                local:
+                    qwerty;
+            } VERSION_1;
+        """))
+        parser = gsl.SymbolFileParser(input_file)
+        versions = parser.parse()
+
+        expected = [
+            gsl.Version('VERSION_1', None, [], [
+                gsl.Symbol('foo', []),
+                gsl.Symbol('bar', ['baz']),
+            ]),
+            gsl.Version('VERSION_2', 'VERSION_1', ['wasd'], [
+                gsl.Symbol('woodly', []),
+                gsl.Symbol('doodly', ['asdf']),
+            ]),
+        ]
+
+        self.assertEqual(expected, versions)
+
+
+class GeneratorTest(unittest.TestCase):
+    def test_omit_version(self):
+        # Thorough testing of the cases involved here is handled by
+        # OmitVersionTest, PrivateVersionTest, and SymbolPresenceTest.
+        src_file = cStringIO.StringIO()
+        version_file = cStringIO.StringIO()
+        generator = gsl.Generator(src_file, version_file, 'arm', 9)
+
+        version = gsl.Version('VERSION_PRIVATE', None, [], [
+            gsl.Symbol('foo', []),
+        ])
+        generator.write_version(version)
+        self.assertEqual('', src_file.getvalue())
+        self.assertEqual('', version_file.getvalue())
+
+        version = gsl.Version('VERSION', None, ['x86'], [
+            gsl.Symbol('foo', []),
+        ])
+        generator.write_version(version)
+        self.assertEqual('', src_file.getvalue())
+        self.assertEqual('', version_file.getvalue())
+
+        version = gsl.Version('VERSION', None, ['introduced=14'], [
+            gsl.Symbol('foo', []),
+        ])
+        generator.write_version(version)
+        self.assertEqual('', src_file.getvalue())
+        self.assertEqual('', version_file.getvalue())
+
+    def test_omit_symbol(self):
+        # Thorough testing of the cases involved here is handled by
+        # SymbolPresenceTest.
+        src_file = cStringIO.StringIO()
+        version_file = cStringIO.StringIO()
+        generator = gsl.Generator(src_file, version_file, 'arm', 9)
+
+        version = gsl.Version('VERSION_1', None, [], [
+            gsl.Symbol('foo', ['x86']),
+        ])
+        generator.write_version(version)
+        self.assertEqual('', src_file.getvalue())
+        self.assertEqual('', version_file.getvalue())
+
+        version = gsl.Version('VERSION_1', None, [], [
+            gsl.Symbol('foo', ['introduced=14']),
+        ])
+        generator.write_version(version)
+        self.assertEqual('', src_file.getvalue())
+        self.assertEqual('', version_file.getvalue())
+
+    def test_write(self):
+        src_file = cStringIO.StringIO()
+        version_file = cStringIO.StringIO()
+        generator = gsl.Generator(src_file, version_file, 'arm', 9)
+
+        versions = [
+            gsl.Version('VERSION_1', None, [], [
+                gsl.Symbol('foo', []),
+                gsl.Symbol('bar', ['var']),
+            ]),
+            gsl.Version('VERSION_2', 'VERSION_1', [], [
+                gsl.Symbol('baz', []),
+            ]),
+            gsl.Version('VERSION_3', 'VERSION_1', [], [
+                gsl.Symbol('qux', ['versioned=14']),
+            ]),
+        ]
+
+        generator.write(versions)
+        expected_src = textwrap.dedent("""\
+            void foo() {}
+            int bar = 0;
+            void baz() {}
+            void qux() {}
+        """)
+        self.assertEqual(expected_src, src_file.getvalue())
+
+        expected_version = textwrap.dedent("""\
+            VERSION_1 {
+                global:
+                    foo;
+                    bar;
+            };
+            VERSION_2 {
+                global:
+                    baz;
+            } VERSION_1;
+        """)
+        self.assertEqual(expected_version, version_file.getvalue())
+
+
+class IntegrationTest(unittest.TestCase):
+    def test_integration(self):
+        input_file = cStringIO.StringIO(textwrap.dedent("""\
+            VERSION_1 {
+                global:
+                    foo; # var
+                    bar; # x86
+                local:
+                    *;
+            };
+
+            VERSION_2 { # arm
+                baz; # introduced=9
+                qux; # versioned=14
+            } VERSION_1;
+
+            VERSION_3 { # introduced=14
+                woodly;
+                doodly; # var
+            } VERSION_2;
+        """))
+        parser = gsl.SymbolFileParser(input_file)
+        versions = parser.parse()
+
+        src_file = cStringIO.StringIO()
+        version_file = cStringIO.StringIO()
+        generator = gsl.Generator(src_file, version_file, 'arm', 9)
+        generator.write(versions)
+
+        expected_src = textwrap.dedent("""\
+            int foo = 0;
+            void baz() {}
+            void qux() {}
+        """)
+        self.assertEqual(expected_src, src_file.getvalue())
+
+        expected_version = textwrap.dedent("""\
+            VERSION_1 {
+                global:
+                    foo;
+            };
+            VERSION_2 {
+                global:
+                    baz;
+            } VERSION_1;
+        """)
+        self.assertEqual(expected_version, version_file.getvalue())
+
+
+def main():
+    suite = unittest.TestLoader().loadTestsFromName(__name__)
+    unittest.TextTestRunner(verbosity=3).run(suite)
+
+
+if __name__ == '__main__':
+    main()