3 files changed, 119 insertions, 29 deletions

diff --git a/include/winapi/cmd_line.hpp b/include/winapi/cmd_line.hpp
index 176cf3d..c6e8c65 100644
--- a/include/winapi/cmd_line.hpp
+++ b/include/winapi/cmd_line.hpp
@@ -29,6 +29,10 @@ public:
     CommandLine(std::string&& argv0, std::vector<std::string>&& args = {})
         : argv0(std::move(argv0)), args(std::move(args)) {}
 
+    CommandLine(const std::vector<std::string>& argv);
+
+    CommandLine(std::vector<std::string>&& argv);
+
     static std::string escape(const std::string&);
 
     static std::string escape_cmd(const std::string&);
@@ -43,6 +47,8 @@ public:
 
     const std::vector<std::string>& get_args() const { return args; }
 
+    std::vector<std::string> get_argv() const;
+
 private:
     static BOOST_CONSTEXPR char token_sep() { return ' '; }
 
@@ -50,6 +56,8 @@ private:
 
     std::vector<std::string> escape_args() const;
 
+    std::vector<std::string> escape_argv() const;
+
     std::string argv0;
     std::vector<std::string> args;
 };
diff --git a/src/cmd_line.cpp b/src/cmd_line.cpp
index 468bb96..2f9be41 100644
--- a/src/cmd_line.cpp
+++ b/src/cmd_line.cpp
@@ -57,6 +57,23 @@ CommandLine do_parse(std::wstring src) {
     return {std::move(argv0), std::move(args)};
 }
 
+std::string split_argv0(std::vector<std::string>& argv) {
+    if (argv.empty()) {
+        throw std::range_error{"argv must contain at least one element"};
+    }
+    const auto argv0 = argv[0];
+    argv.erase(argv.begin());
+    return argv0;
+}
+
+std::vector<std::string> escape_all(const std::vector<std::string>& xs) {
+    std::vector<std::string> escaped;
+    escaped.reserve(xs.size());
+    for (const auto& x : xs)
+        escaped.emplace_back(CommandLine::escape(x));
+    return escaped;
+}
+
 } // namespace
 
 CommandLine CommandLine::query() {
@@ -71,17 +88,21 @@ CommandLine CommandLine::from_main(int argc, wchar_t* argv[]) {
     if (argc < 1)
         throw std::range_error{"argc must be a positive number"};
 
-    std::string argv0{narrow(argv[0])};
-    --argc;
-    ++argv;
-
-    std::vector<std::string> args;
-    args.reserve(argc);
+    std::vector<std::string> utf8_argv;
+    utf8_argv.reserve(argc);
 
     for (int i = 0; i < argc; ++i)
-        args.emplace_back(narrow(argv[i]));
+        utf8_argv.emplace_back(narrow(argv[i]));
 
-    return {std::move(argv0), std::move(args)};
+    return {std::move(utf8_argv)};
+}
+
+CommandLine::CommandLine(const std::vector<std::string>& argv) : args(argv) {
+    argv0 = split_argv0(args);
+}
+
+CommandLine::CommandLine(std::vector<std::string>&& argv) : args(std::move(argv)) {
+    argv0 = split_argv0(args);
 }
 
 std::string CommandLine::escape(const std::string& arg) {
@@ -135,23 +156,25 @@ std::string CommandLine::escape_cmd(const std::string& arg) {
 }
 
 std::string CommandLine::to_string() const {
-    std::ostringstream oss;
-    oss << escape(get_argv0());
-    if (has_args())
-        oss << token_sep() << args_to_string();
-    return oss.str();
+    return boost::algorithm::join(escape_argv(), std::string{token_sep()});
 }
 
 std::string CommandLine::args_to_string() const {
     return boost::algorithm::join(escape_args(), std::string{token_sep()});
 }
 
+std::vector<std::string> CommandLine::get_argv() const {
+    auto argv = get_args();
+    argv.emplace(argv.begin(), get_argv0());
+    return argv;
+}
+
 std::vector<std::string> CommandLine::escape_args() const {
-    std::vector<std::string> safe;
-    safe.reserve(args.size());
-    for (const auto& arg : args)
-        safe.emplace_back(escape(arg));
-    return safe;
+    return escape_all(get_args());
+}
+
+std::vector<std::string> CommandLine::escape_argv() const {
+    return escape_all(get_argv());
 }
 
 } // namespace winapi
diff --git a/test/unit_tests/cmd_line.cpp b/test/unit_tests/cmd_line.cpp
index 99646ff..42f4a93 100644
--- a/test/unit_tests/cmd_line.cpp
+++ b/test/unit_tests/cmd_line.cpp
@@ -5,30 +5,89 @@
 
 #include <winapi/cmd_line.hpp>
 
+// clang-format off
+// The order matters for older Boost versions.
 #include <boost/test/unit_test.hpp>
+#include <boost/test/data/test_case.hpp>
+#include <boost/test/data/monomorphic.hpp>
+// clang-format on
 
+#include <ostream>
 #include <string>
+#include <vector>
+
+using namespace winapi;
+
+namespace std {
+
+ostream& operator<<(ostream& os, const vector<string>& xs) {
+    os << "[\n";
+    for (const auto& x : xs) {
+        os << x << '\n';
+    }
+    os << "]";
+    return os;
+}
+
+} // namespace std
+
+BOOST_TEST_SPECIALIZED_COLLECTION_COMPARE(std::vector<std::string>);
+
+namespace {
+
+// MSDN examples
+// https://docs.microsoft.com/en-us/cpp/c-language/parsing-c-command-line-arguments?view=vs-2019
+
+const std::vector<std::string> msdn_string{
+    R"(test.exe "abc" d e)",
+    R"(test.exe a\\\b d"e f"g h)",
+    R"(test.exe a\\\"b c d)",
+    R"(test.exe a\\\\"b c" d e)",
+};
+
+const std::vector<std::vector<std::string>> msdn_argv{
+    {"test.exe", "abc", "d", "e"},
+    {"test.exe", R"(a\\\b)", "de fg", "h"},
+    {"test.exe", R"(a\"b)", "c", "d"},
+    {"test.exe", R"(a\\b c)", "d", "e"},
+};
+
+} // namespace
 
 BOOST_AUTO_TEST_SUITE(cmd_line_tests)
 
 BOOST_AUTO_TEST_CASE(query) {
-    const auto cmd_line = winapi::CommandLine::query();
-    BOOST_TEST(!cmd_line.get_argv0().empty());
-    BOOST_TEST_MESSAGE(cmd_line.get_argv0());
+    const auto cmd_line = CommandLine::query();
+    BOOST_TEST(!cmd_line.get_argv0().empty(), "argv[0]: " << cmd_line.get_argv0());
 }
 
-BOOST_AUTO_TEST_CASE(escape) {
-    wchar_t* argv[] = {
-        L"test.exe",
-        L"arg1 arg2",
-        LR"(path\to\file)",
-        LR"(path\to\dir\)",
-        LR"(weird\\argument)",
+BOOST_AUTO_TEST_CASE(to_string) {
+    const std::vector<std::string> argv{
+        "test.exe",
+        "arg1 arg2",
+        R"(path\to\file)",
+        R"(path\to\dir\)",
+        R"(weird\\argument)",
     };
-    const auto cmd_line = winapi::CommandLine::from_main(5, argv);
+    const CommandLine cmd_line{argv};
     const auto expected =
         R"("test.exe" "arg1 arg2" "path\to\file" "path\to\dir\\" "weird\\argument")";
     BOOST_TEST(cmd_line.to_string() == expected);
 }
 
+BOOST_DATA_TEST_CASE(msdn_parse,
+                     boost::unit_test::data::make(msdn_string) ^ msdn_argv,
+                     input,
+                     expected) {
+    const auto cmd_line = CommandLine::parse(input);
+    const auto actual = cmd_line.get_argv();
+    BOOST_TEST(actual == expected, "actual: " << actual);
+}
+
+BOOST_DATA_TEST_CASE(msdn_to_string, msdn_argv, argv) {
+    const CommandLine cmd_line{argv};
+    const auto actual = CommandLine::parse(cmd_line.to_string()).get_argv();
+    BOOST_TEST(actual == argv, "actual: " << actual);
+}
+
 BOOST_AUTO_TEST_SUITE_END()