llvm/unittests/ADT/TwineTest.cpp

   1 //===- TwineTest.cpp - Twine unit tests -----------------------------------===//
   2 //
   3 // Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.
   4 // See https://llvm.org/LICENSE.txt for license information.
   5 // SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
   6 //
   7 //===----------------------------------------------------------------------===//
   8
   9 #include "llvm/ADT/Twine.h"
  10 #include "llvm/ADT/SmallString.h"
  11 #include "llvm/Support/FormatAdapters.h"
  12 #include "llvm/Support/FormatVariadic.h"
  13 #include "llvm/Support/raw_ostream.h"
  14 #include "gtest/gtest.h"
  15 using namespace llvm;
  16
  17 namespace {
  18
  19 std::string repr(const Twine &Value) {
  20   std::string res;
  21   llvm::raw_string_ostream OS(res);
  22   Value.printRepr(OS);
  23   return OS.str();
  24 }
  25
  26 TEST(TwineTest, Construction) {
  27   EXPECT_EQ("", Twine().str());
  28   EXPECT_EQ("hi", Twine("hi").str());
  29   EXPECT_EQ("hi", Twine(std::string("hi")).str());
  30   EXPECT_EQ("hi", Twine(StringRef("hi")).str());
  31   EXPECT_EQ("hi", Twine(StringRef(std::string("hi"))).str());
  32   EXPECT_EQ("hi", Twine(StringRef("hithere", 2)).str());
  33   EXPECT_EQ("hi", Twine(SmallString<4>("hi")).str());
  34   EXPECT_EQ("hi", Twine(formatv("{0}", "hi")).str());
  35   EXPECT_EQ("hi", Twine(std::string_view("hi")).str());
  36 }
  37
  38 TEST(TwineTest, Numbers) {
  39   EXPECT_EQ("123", Twine(123U).str());
  40   EXPECT_EQ("123", Twine(123).str());
  41   EXPECT_EQ("-123", Twine(-123).str());
  42   EXPECT_EQ("123", Twine(123).str());
  43   EXPECT_EQ("-123", Twine(-123).str());
  44
  45   EXPECT_EQ("7b", Twine::utohexstr(123).str());
  46 }
  47
  48 TEST(TwineTest, Characters) {
  49   EXPECT_EQ("x", Twine('x').str());
  50   EXPECT_EQ("x", Twine(static_cast<unsigned char>('x')).str());
  51   EXPECT_EQ("x", Twine(static_cast<signed char>('x')).str());
  52 }
  53
  54 TEST(TwineTest, Concat) {
  55   // Check verse repr, since we care about the actual representation not just
  56   // the result.
  57
  58   // Concat with null.
  59   EXPECT_EQ("(Twine null empty)",
  60             repr(Twine("hi").concat(Twine::createNull())));
  61   EXPECT_EQ("(Twine null empty)",
  62             repr(Twine::createNull().concat(Twine("hi"))));
  63
  64   // Concat with empty.
  65   EXPECT_EQ("(Twine cstring:\"hi\" empty)",
  66             repr(Twine("hi").concat(Twine())));
  67   EXPECT_EQ("(Twine cstring:\"hi\" empty)",
  68             repr(Twine().concat(Twine("hi"))));
  69   EXPECT_EQ("(Twine ptrAndLength:\"hi\" empty)",
  70             repr(Twine().concat(Twine(SmallString<5>("hi")))));
  71   EXPECT_EQ("(Twine formatv:\"howdy\" empty)",
  72             repr(Twine(formatv("howdy")).concat(Twine())));
  73   EXPECT_EQ("(Twine formatv:\"howdy\" empty)",
  74             repr(Twine().concat(Twine(formatv("howdy")))));
  75   EXPECT_EQ("(Twine ptrAndLength:\"hey\" cstring:\"there\")",
  76             repr(Twine(SmallString<7>("hey")).concat(Twine("there"))));
  77   EXPECT_EQ("(Twine ptrAndLength:\"hey\" cstring:\"there\")",
  78             repr(Twine(std::string_view("hey")).concat(Twine("there"))));
  79
  80   // Concatenation of unary ropes.
  81   EXPECT_EQ("(Twine cstring:\"a\" cstring:\"b\")",
  82             repr(Twine("a").concat(Twine("b"))));
  83
  84   // Concatenation of other ropes.
  85   EXPECT_EQ("(Twine rope:(Twine cstring:\"a\" cstring:\"b\") cstring:\"c\")",
  86             repr(Twine("a").concat(Twine("b")).concat(Twine("c"))));
  87   EXPECT_EQ("(Twine cstring:\"a\" rope:(Twine cstring:\"b\" cstring:\"c\"))",
  88             repr(Twine("a").concat(Twine("b").concat(Twine("c")))));
  89   EXPECT_EQ(
  90       "(Twine cstring:\"a\" rope:(Twine ptrAndLength:\"b\" cstring:\"c\"))",
  91       repr(Twine("a").concat(Twine(SmallString<3>("b")).concat(Twine("c")))));
  92 }
  93
  94 TEST(TwineTest, toNullTerminatedStringRef) {
  95   SmallString<8> storage;
  96   EXPECT_EQ(0, *Twine("hello").toNullTerminatedStringRef(storage).end());
  97   EXPECT_EQ(0,
  98            *Twine(StringRef("hello")).toNullTerminatedStringRef(storage).end());
  99   EXPECT_EQ(0, *Twine(SmallString<11>("hello"))
 100                     .toNullTerminatedStringRef(storage)
 101                     .end());
 102   EXPECT_EQ(0, *Twine(formatv("{0}{1}", "how", "dy"))
 103                     .toNullTerminatedStringRef(storage)
 104                     .end());
 105 }
 106
 107 TEST(TwineTest, LazyEvaluation) {
 108   struct formatter : FormatAdapter<int> {
 109     explicit formatter(int &Count) : FormatAdapter(0), Count(Count) {}
 110     int &Count;
 111
 112     void format(raw_ostream &OS, StringRef Style) override { ++Count; }
 113   };
 114
 115   int Count = 0;
 116   formatter Formatter(Count);
 117   (void)Twine(formatv("{0}", Formatter));
 118   EXPECT_EQ(0, Count);
 119   (void)Twine(formatv("{0}", Formatter)).str();
 120   EXPECT_EQ(1, Count);
 121 }
 122
 123   // I suppose linking in the entire code generator to add a unit test to check
 124   // the code size of the concat operation is overkill... :)
 125
 126 } // end anonymous namespace