abseil-cpp/absl/strings/internal/str_format/parser_test.cc

#include "absl/strings/internal/str_format/parser.h"

#include <string.h>
#include "gtest/gtest.h"
#include "absl/base/macros.h"

namespace absl {
namespace str_format_internal {

namespace {

TEST(LengthModTest, Names) {
  struct Expectation {
    int line;
    LengthMod::Id id;
    const char *name;
  };
  const Expectation kExpect[] = {
    {__LINE__, LengthMod::none, ""  },
    {__LINE__, LengthMod::h,    "h" },
    {__LINE__, LengthMod::hh,   "hh"},
    {__LINE__, LengthMod::l,    "l" },
    {__LINE__, LengthMod::ll,   "ll"},
    {__LINE__, LengthMod::L,    "L" },
    {__LINE__, LengthMod::j,    "j" },
    {__LINE__, LengthMod::z,    "z" },
    {__LINE__, LengthMod::t,    "t" },
    {__LINE__, LengthMod::q,    "q" },
  };
  EXPECT_EQ(ABSL_ARRAYSIZE(kExpect), LengthMod::kNumValues);
  for (auto e : kExpect) {
    SCOPED_TRACE(e.line);
    LengthMod mod = LengthMod::FromId(e.id);
    EXPECT_EQ(e.id, mod.id());
    EXPECT_EQ(e.name, mod.name());
  }
}

TEST(ConversionCharTest, Names) {
  struct Expectation {
    ConversionChar::Id id;
    char name;
  };
  // clang-format off
  const Expectation kExpect[] = {
#define X(c) {ConversionChar::c, #c[0]}
    X(c), X(C), X(s), X(S),                          // text
    X(d), X(i), X(o), X(u), X(x), X(X),              // int
    X(f), X(F), X(e), X(E), X(g), X(G), X(a), X(A),  // float
    X(n), X(p),                                      // misc
#undef X
    {ConversionChar::none, '\0'},
  };
  // clang-format on
  EXPECT_EQ(ABSL_ARRAYSIZE(kExpect), ConversionChar::kNumValues);
  for (auto e : kExpect) {
    SCOPED_TRACE(e.name);
    ConversionChar v = ConversionChar::FromId(e.id);
    EXPECT_EQ(e.id, v.id());
    EXPECT_EQ(e.name, v.Char());
  }
}

class ConsumeUnboundConversionTest : public ::testing::Test {
 public:
  typedef UnboundConversion Props;
  string_view Consume(string_view* src) {
    int next = 0;
    const char* prev_begin = src->begin();
    o = UnboundConversion();  // refresh
    ConsumeUnboundConversion(src, &o, &next);
    return {prev_begin, static_cast<size_t>(src->begin() - prev_begin)};
  }

  bool Run(const char *fmt, bool force_positional = false) {
    string_view src = fmt;
    int next = force_positional ? -1 : 0;
    o = UnboundConversion();  // refresh
    return ConsumeUnboundConversion(&src, &o, &next) && src.empty();
  }
  UnboundConversion o;
};

TEST_F(ConsumeUnboundConversionTest, ConsumeSpecification) {
  struct Expectation {
    int line;
    const char *src;
    const char *out;
    const char *src_post;
  };
  const Expectation kExpect[] = {
    {__LINE__, "",     "",     ""  },
    {__LINE__, "b",    "",     "b" },  // 'b' is invalid
    {__LINE__, "ba",   "",     "ba"},  // 'b' is invalid
    {__LINE__, "l",    "",     "l" },  // just length mod isn't okay
    {__LINE__, "d",    "d",    ""  },  // basic
    {__LINE__, "d ",   "d",    " " },  // leave suffix
    {__LINE__, "dd",   "d",    "d" },  // don't be greedy
    {__LINE__, "d9",   "d",    "9" },  // leave non-space suffix
    {__LINE__, "dzz",  "d",    "zz"},  // length mod as suffix
    {__LINE__, "1$*2$d", "1$*2$d", ""  },  // arg indexing and * allowed.
    {__LINE__, "0-14.3hhd", "0-14.3hhd", ""},  // precision, width
    {__LINE__, " 0-+#14.3hhd", " 0-+#14.3hhd", ""},  // flags
  };
  for (const auto& e : kExpect) {
    SCOPED_TRACE(e.line);
    string_view src = e.src;
    EXPECT_EQ(e.src, src);
    string_view out = Consume(&src);
    EXPECT_EQ(e.out, out);
    EXPECT_EQ(e.src_post, src);
  }
}

TEST_F(ConsumeUnboundConversionTest, BasicConversion) {
  EXPECT_FALSE(Run(""));
  EXPECT_FALSE(Run("z"));

  EXPECT_FALSE(Run("dd"));  // no excess allowed

  EXPECT_TRUE(Run("d"));
  EXPECT_EQ('d', o.conv.Char());
  EXPECT_FALSE(o.width.is_from_arg());
  EXPECT_LT(o.width.value(), 0);
  EXPECT_FALSE(o.precision.is_from_arg());
  EXPECT_LT(o.precision.value(), 0);
  EXPECT_EQ(1, o.arg_position);
  EXPECT_EQ(LengthMod::none, o.length_mod.id());
}

TEST_F(ConsumeUnboundConversionTest, ArgPosition) {
  EXPECT_TRUE(Run("d"));
  EXPECT_EQ(1, o.arg_position);
  EXPECT_TRUE(Run("3$d"));
  EXPECT_EQ(3, o.arg_position);
  EXPECT_TRUE(Run("1$d"));
  EXPECT_EQ(1, o.arg_position);
  EXPECT_TRUE(Run("1$d", true));
  EXPECT_EQ(1, o.arg_position);
  EXPECT_TRUE(Run("123$d"));
  EXPECT_EQ(123, o.arg_position);
  EXPECT_TRUE(Run("123$d", true));
  EXPECT_EQ(123, o.arg_position);
  EXPECT_TRUE(Run("10$d"));
  EXPECT_EQ(10, o.arg_position);
  EXPECT_TRUE(Run("10$d", true));
  EXPECT_EQ(10, o.arg_position);

  // Position can't be zero.
  EXPECT_FALSE(Run("0$d"));
  EXPECT_FALSE(Run("0$d", true));
  EXPECT_FALSE(Run("1$*0$d"));
  EXPECT_FALSE(Run("1$.*0$d"));

  // Position can't start with a zero digit at all. That is not a 'decimal'.
  EXPECT_FALSE(Run("01$p"));
  EXPECT_FALSE(Run("01$p", true));
  EXPECT_FALSE(Run("1$*01$p"));
  EXPECT_FALSE(Run("1$.*01$p"));
}

TEST_F(ConsumeUnboundConversionTest, WidthAndPrecision) {
  EXPECT_TRUE(Run("14d"));
  EXPECT_EQ('d', o.conv.Char());
  EXPECT_FALSE(o.width.is_from_arg());
  EXPECT_EQ(14, o.width.value());
  EXPECT_FALSE(o.precision.is_from_arg());
  EXPECT_LT(o.precision.value(), 0);

  EXPECT_TRUE(Run("14.d"));
  EXPECT_FALSE(o.width.is_from_arg());
  EXPECT_FALSE(o.precision.is_from_arg());
  EXPECT_EQ(14, o.width.value());
  EXPECT_EQ(0, o.precision.value());

  EXPECT_TRUE(Run(".d"));
  EXPECT_FALSE(o.width.is_from_arg());
  EXPECT_LT(o.width.value(), 0);
  EXPECT_FALSE(o.precision.is_from_arg());
  EXPECT_EQ(0, o.precision.value());

  EXPECT_TRUE(Run(".5d"));
  EXPECT_FALSE(o.width.is_from_arg());
  EXPECT_LT(o.width.value(), 0);
  EXPECT_FALSE(o.precision.is_from_arg());
  EXPECT_EQ(5, o.precision.value());

  EXPECT_TRUE(Run(".0d"));
  EXPECT_FALSE(o.width.is_from_arg());
  EXPECT_LT(o.width.value(), 0);
  EXPECT_FALSE(o.precision.is_from_arg());
  EXPECT_EQ(0, o.precision.value());

  EXPECT_TRUE(Run("14.5d"));
  EXPECT_FALSE(o.width.is_from_arg());
  EXPECT_FALSE(o.precision.is_from_arg());
  EXPECT_EQ(14, o.width.value());
  EXPECT_EQ(5, o.precision.value());

  EXPECT_TRUE(Run("*.*d"));
  EXPECT_TRUE(o.width.is_from_arg());
  EXPECT_EQ(1, o.width.get_from_arg());
  EXPECT_TRUE(o.precision.is_from_arg());
  EXPECT_EQ(2, o.precision.get_from_arg());
  EXPECT_EQ(3, o.arg_position);

  EXPECT_TRUE(Run("*d"));
  EXPECT_TRUE(o.width.is_from_arg());
  EXPECT_EQ(1, o.width.get_from_arg());
  EXPECT_FALSE(o.precision.is_from_arg());
  EXPECT_LT(o.precision.value(), 0);
  EXPECT_EQ(2, o.arg_position);

  EXPECT_TRUE(Run(".*d"));
  EXPECT_FALSE(o.width.is_from_arg());
  EXPECT_LT(o.width.value(), 0);
  EXPECT_TRUE(o.precision.is_from_arg());
  EXPECT_EQ(1, o.precision.get_from_arg());
  EXPECT_EQ(2, o.arg_position);

  // mixed implicit and explicit: didn't specify arg position.
  EXPECT_FALSE(Run("*23$.*34$d"));

  EXPECT_TRUE(Run("12$*23$.*34$d"));
  EXPECT_EQ(12, o.arg_position);
  EXPECT_TRUE(o.width.is_from_arg());
  EXPECT_EQ(23, o.width.get_from_arg());
  EXPECT_TRUE(o.precision.is_from_arg());
  EXPECT_EQ(34, o.precision.get_from_arg());

  EXPECT_TRUE(Run("2$*5$.*9$d"));
  EXPECT_EQ(2, o.arg_position);
  EXPECT_TRUE(o.width.is_from_arg());
  EXPECT_EQ(5, o.width.get_from_arg());
  EXPECT_TRUE(o.precision.is_from_arg());
  EXPECT_EQ(9, o.precision.get_from_arg());

  EXPECT_FALSE(Run(".*0$d")) << "no arg 0";
}

TEST_F(ConsumeUnboundConversionTest, Flags) {
  static const char kAllFlags[] = "-+ #0";
  static const int kNumFlags = ABSL_ARRAYSIZE(kAllFlags) - 1;
  for (int rev = 0; rev < 2; ++rev) {
    for (int i = 0; i < 1 << kNumFlags; ++i) {
      std::string fmt;
      for (int k = 0; k < kNumFlags; ++k)
        if ((i >> k) & 1) fmt += kAllFlags[k];
      // flag order shouldn't matter
      if (rev == 1) { std::reverse(fmt.begin(), fmt.end()); }
      fmt += 'd';
      SCOPED_TRACE(fmt);
      EXPECT_TRUE(Run(fmt.c_str()));
      EXPECT_EQ(fmt.find('-') == std::string::npos, !o.flags.left);
      EXPECT_EQ(fmt.find('+') == std::string::npos, !o.flags.show_pos);
      EXPECT_EQ(fmt.find(' ') == std::string::npos, !o.flags.sign_col);
      EXPECT_EQ(fmt.find('#') == std::string::npos, !o.flags.alt);
      EXPECT_EQ(fmt.find('0') == std::string::npos, !o.flags.zero);
    }
  }
}

TEST_F(ConsumeUnboundConversionTest, BasicFlag) {
  // Flag is on
  for (const char* fmt : {"d", "llx", "G", "1$X"}) {
    SCOPED_TRACE(fmt);
    EXPECT_TRUE(Run(fmt));
    EXPECT_TRUE(o.flags.basic);
  }

  // Flag is off
  for (const char* fmt : {"3d", ".llx", "-G", "1$#X"}) {
    SCOPED_TRACE(fmt);
    EXPECT_TRUE(Run(fmt));
    EXPECT_FALSE(o.flags.basic);
  }
}

struct SummarizeConsumer {
  std::string* out;
  explicit SummarizeConsumer(std::string* out) : out(out) {}

  bool Append(string_view s) {
    *out += "[" + std::string(s) + "]";
    return true;
  }

  bool ConvertOne(const UnboundConversion& conv, string_view s) {
    *out += "{";
    *out += std::string(s);
    *out += ":";
    *out += std::to_string(conv.arg_position) + "$";
    if (conv.width.is_from_arg()) {
      *out += std::to_string(conv.width.get_from_arg()) + "$*";
    }
    if (conv.precision.is_from_arg()) {
      *out += "." + std::to_string(conv.precision.get_from_arg()) + "$*";
    }
    *out += conv.conv.Char();
    *out += "}";
    return true;
  }
};

std::string SummarizeParsedFormat(const ParsedFormatBase& pc) {
  std::string out;
  if (!pc.ProcessFormat(SummarizeConsumer(&out))) out += "!";
  return out;
}

class ParsedFormatTest : public testing::Test {};

TEST_F(ParsedFormatTest, ValueSemantics) {
  ParsedFormatBase p1({}, true, {});  // empty format
  EXPECT_EQ("", SummarizeParsedFormat(p1));

  ParsedFormatBase p2 = p1;  // copy construct (empty)
  EXPECT_EQ(SummarizeParsedFormat(p1), SummarizeParsedFormat(p2));

  p1 = ParsedFormatBase("hello%s", true, {Conv::s});  // move assign
  EXPECT_EQ("[hello]{s:1$s}", SummarizeParsedFormat(p1));

  ParsedFormatBase p3 = p1;  // copy construct (nonempty)
  EXPECT_EQ(SummarizeParsedFormat(p1), SummarizeParsedFormat(p3));

  using std::swap;
  swap(p1, p2);
  EXPECT_EQ("", SummarizeParsedFormat(p1));
  EXPECT_EQ("[hello]{s:1$s}", SummarizeParsedFormat(p2));
  swap(p1, p2);  // undo

  p2 = p1;  // copy assign
  EXPECT_EQ(SummarizeParsedFormat(p1), SummarizeParsedFormat(p2));
}

struct ExpectParse {
  const char* in;
  std::initializer_list<Conv> conv_set;
  const char* out;
};

TEST_F(ParsedFormatTest, Parsing) {
  // Parse should be equivalent to that obtained by ConversionParseIterator.
  // No need to retest the parsing edge cases here.
  const ExpectParse kExpect[] = {
      {"", {}, ""},
      {"ab", {}, "[ab]"},
      {"a%d", {Conv::d}, "[a]{d:1$d}"},
      {"a%+d", {Conv::d}, "[a]{+d:1$d}"},
      {"a% d", {Conv::d}, "[a]{ d:1$d}"},
      {"a%b %d", {}, "[a]!"},  // stop after error
  };
  for (const auto& e : kExpect) {
    SCOPED_TRACE(e.in);
    EXPECT_EQ(e.out,
              SummarizeParsedFormat(ParsedFormatBase(e.in, false, e.conv_set)));
  }
}

TEST_F(ParsedFormatTest, ParsingFlagOrder) {
  const ExpectParse kExpect[] = {
      {"a%+ 0d", {Conv::d}, "[a]{+ 0d:1$d}"},
      {"a%+0 d", {Conv::d}, "[a]{+0 d:1$d}"},
      {"a%0+ d", {Conv::d}, "[a]{0+ d:1$d}"},
      {"a% +0d", {Conv::d}, "[a]{ +0d:1$d}"},
      {"a%0 +d", {Conv::d}, "[a]{0 +d:1$d}"},
      {"a% 0+d", {Conv::d}, "[a]{ 0+d:1$d}"},
      {"a%+   0+d", {Conv::d}, "[a]{+   0+d:1$d}"},
  };
  for (const auto& e : kExpect) {
    SCOPED_TRACE(e.in);
    EXPECT_EQ(e.out,
              SummarizeParsedFormat(ParsedFormatBase(e.in, false, e.conv_set)));
  }
}

}  // namespace
}  // namespace str_format_internal
}  // namespace absl