init: add unit tests for tokenizer.cpp

Test: this unit test
Change-Id: Iae24f3bf7850dd4b298281f6608bce195096d60a
diff --git a/init/Android.bp b/init/Android.bp
index cf7637f..625fb94 100644
--- a/init/Android.bp
+++ b/init/Android.bp
@@ -179,6 +179,7 @@
         "rlimit_parser_test.cpp",
         "service_test.cpp",
         "subcontext_test.cpp",
+        "tokenizer_test.cpp",
         "ueventd_test.cpp",
         "util_test.cpp",
     ],
diff --git a/init/tokenizer_test.cpp b/init/tokenizer_test.cpp
new file mode 100644
index 0000000..acfc7c7
--- /dev/null
+++ b/init/tokenizer_test.cpp
@@ -0,0 +1,163 @@
+//
+// Copyright (C) 2018 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.
+//
+
+#include "tokenizer.h"
+
+#include <string>
+#include <vector>
+
+#include <gtest/gtest.h>
+
+namespace android {
+namespace init {
+
+namespace {
+
+void RunTest(const std::string& data, const std::vector<std::vector<std::string>>& expected_tokens) {
+    auto data_copy = std::string{data};
+    data_copy.push_back('\n');  // TODO: fix tokenizer
+    data_copy.push_back('\0');
+
+    parse_state state;
+    state.line = 0;
+    state.ptr = data_copy.data();
+    state.nexttoken = 0;
+
+    std::vector<std::string> current_line;
+    std::vector<std::vector<std::string>> tokens;
+
+    while (true) {
+        switch (next_token(&state)) {
+            case T_EOF:
+                EXPECT_EQ(expected_tokens, tokens) << data;
+                return;
+            case T_NEWLINE:
+                tokens.emplace_back(std::move(current_line));
+                break;
+            case T_TEXT:
+                current_line.emplace_back(state.text);
+                break;
+        }
+    }
+}
+
+}  // namespace
+
+TEST(tokenizer, null) {
+    RunTest("", {{}});
+}
+
+TEST(tokenizer, simple_oneline) {
+    RunTest("one two\tthree\rfour", {{"one", "two", "three", "four"}});
+}
+
+TEST(tokenizer, simple_multiline) {
+    RunTest("1 2 3\n4 5 6\n7 8 9", {{"1", "2", "3"}, {"4", "5", "6"}, {"7", "8", "9"}});
+}
+
+TEST(tokenizer, preceding_space) {
+    // Preceding spaces are ignored.
+    RunTest("    1 2 3\n\t\t\t\t4 5 6\n\r\r\r\r7 8 9",
+            {{"1", "2", "3"}, {"4", "5", "6"}, {"7", "8", "9"}});
+}
+
+TEST(tokenizer, comments) {
+    // Entirely commented lines still produce a T_NEWLINE token for tracking line count.
+    RunTest("1 2 3\n#4 5 6\n7 8 9", {{"1", "2", "3"}, {}, {"7", "8", "9"}});
+
+    RunTest("#1 2 3\n4 5 6\n7 8 9", {{}, {"4", "5", "6"}, {"7", "8", "9"}});
+
+    RunTest("1 2 3\n4 5 6\n#7 8 9", {{"1", "2", "3"}, {"4", "5", "6"}, {}});
+
+    RunTest("1 2 #3\n4 #5 6\n#7 8 9", {{"1", "2"}, {"4"}, {}});
+}
+
+TEST(tokenizer, control_chars) {
+    // Literal \n, \r, \t, and \\ produce the control characters \n, \r, \t, and \\ respectively.
+    // Literal \? produces ? for all other character '?'
+
+    RunTest(R"(1 token\ntoken 2)", {{"1", "token\ntoken", "2"}});
+    RunTest(R"(1 token\rtoken 2)", {{"1", "token\rtoken", "2"}});
+    RunTest(R"(1 token\ttoken 2)", {{"1", "token\ttoken", "2"}});
+    RunTest(R"(1 token\\token 2)", {{"1", "token\\token", "2"}});
+    RunTest(R"(1 token\btoken 2)", {{"1", "tokenbtoken", "2"}});
+
+    RunTest(R"(1 token\n 2)", {{"1", "token\n", "2"}});
+    RunTest(R"(1 token\r 2)", {{"1", "token\r", "2"}});
+    RunTest(R"(1 token\t 2)", {{"1", "token\t", "2"}});
+    RunTest(R"(1 token\\ 2)", {{"1", "token\\", "2"}});
+    RunTest(R"(1 token\b 2)", {{"1", "tokenb", "2"}});
+
+    RunTest(R"(1 \ntoken 2)", {{"1", "\ntoken", "2"}});
+    RunTest(R"(1 \rtoken 2)", {{"1", "\rtoken", "2"}});
+    RunTest(R"(1 \ttoken 2)", {{"1", "\ttoken", "2"}});
+    RunTest(R"(1 \\token 2)", {{"1", "\\token", "2"}});
+    RunTest(R"(1 \btoken 2)", {{"1", "btoken", "2"}});
+
+    RunTest(R"(1 \n 2)", {{"1", "\n", "2"}});
+    RunTest(R"(1 \r 2)", {{"1", "\r", "2"}});
+    RunTest(R"(1 \t 2)", {{"1", "\t", "2"}});
+    RunTest(R"(1 \\ 2)", {{"1", "\\", "2"}});
+    RunTest(R"(1 \b 2)", {{"1", "b", "2"}});
+}
+
+TEST(tokenizer, cr_lf) {
+    // \ before \n, \r, or \r\n is interpreted as a line continuation
+    // Extra whitespace on the next line is eaten, except \r unlike in the above tests.
+
+    RunTest("lf\\\ncont", {{"lfcont"}});
+    RunTest("lf\\\n    \t\t\t\tcont", {{"lfcont"}});
+
+    RunTest("crlf\\\r\ncont", {{"crlfcont"}});
+    RunTest("crlf\\\r\n    \t\t\t\tcont", {{"crlfcont"}});
+
+    RunTest("cr\\\rcont", {{"crcont"}});
+
+    RunTest("lfspace \\\ncont", {{"lfspace", "cont"}});
+    RunTest("lfspace \\\n    \t\t\t\tcont", {{"lfspace", "cont"}});
+
+    RunTest("crlfspace \\\r\ncont", {{"crlfspace", "cont"}});
+    RunTest("crlfspace \\\r\n    \t\t\t\tcont", {{"crlfspace", "cont"}});
+
+    RunTest("crspace \\\rcont", {{"crspace", "cont"}});
+}
+
+TEST(tokenizer, quoted) {
+    RunTest("\"quoted simple string\"", {{"quoted simple string"}});
+
+    // Unterminated quotes just return T_EOF without any T_NEWLINE.
+    RunTest("\"unterminated quoted string", {});
+
+    RunTest("\"1 2 3\"\n \"unterminated quoted string", {{"1 2 3"}});
+
+    // Escaping quotes is not allowed and are treated as an unterminated quoted string.
+    RunTest("\"quoted escaped quote\\\"\"", {});
+    RunTest("\"quoted escaped\\\" quote\"", {});
+    RunTest("\"\\\"quoted escaped quote\"", {});
+
+    RunTest("\"quoted control characters \\n \\r \\t \\\\ \\b \\\r \\\n \r \n\"",
+            {{"quoted control characters \\n \\r \\t \\\\ \\b \\\r \\\n \r \n"}});
+
+    RunTest("\"quoted simple string\" \"second quoted string\"",
+            {{"quoted simple string", "second quoted string"}});
+
+    RunTest("\"# comment quoted string\"", {{"# comment quoted string"}});
+
+    RunTest("\"Adjacent \"\"quoted strings\"", {{"Adjacent quoted strings"}});
+}
+
+}  // namespace init
+}  // namespace android