http://git-wip-us.apache.org/repos/asf/marmotta/blob/0eb556da/libraries/ostrich/backend/3rdparty/abseil/absl/strings/str_split_test.cc ---------------------------------------------------------------------- diff --git a/libraries/ostrich/backend/3rdparty/abseil/absl/strings/str_split_test.cc b/libraries/ostrich/backend/3rdparty/abseil/absl/strings/str_split_test.cc new file mode 100644 index 0000000..c172a76 --- /dev/null +++ b/libraries/ostrich/backend/3rdparty/abseil/absl/strings/str_split_test.cc @@ -0,0 +1,907 @@ +// Copyright 2017 The Abseil Authors. +// +// 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 "absl/strings/str_split.h" + +#include <deque> +#include <initializer_list> +#include <list> +#include <map> +#include <memory> +#include <string> +#include <type_traits> +#include <unordered_map> +#include <unordered_set> +#include <vector> + +#include "gmock/gmock.h" +#include "gtest/gtest.h" +#include "absl/base/dynamic_annotations.h" // for RunningOnValgrind +#include "absl/base/macros.h" +#include "absl/strings/numbers.h" + +namespace { + +using ::testing::ElementsAre; +using ::testing::Pair; +using ::testing::UnorderedElementsAre; + +// This tests the overall split API, which is made up of the absl::StrSplit() +// function and the Delimiter objects in the absl:: namespace. +// This TEST macro is outside of any namespace to require full specification of +// namespaces just like callers will need to use. +TEST(Split, APIExamples) { + { + // Passes std::string delimiter. Assumes the default of Literal. + std::vector<std::string> v = absl::StrSplit("a,b,c", ','); + EXPECT_THAT(v, ElementsAre("a", "b", "c")); + + // Equivalent to... + using absl::ByString; + v = absl::StrSplit("a,b,c", ByString(",")); + EXPECT_THAT(v, ElementsAre("a", "b", "c")); + + // Equivalent to... + EXPECT_THAT(absl::StrSplit("a,b,c", ByString(",")), + ElementsAre("a", "b", "c")); + } + + { + // Same as above, but using a single character as the delimiter. + std::vector<std::string> v = absl::StrSplit("a,b,c", ','); + EXPECT_THAT(v, ElementsAre("a", "b", "c")); + + // Equivalent to... + using absl::ByChar; + v = absl::StrSplit("a,b,c", ByChar(',')); + EXPECT_THAT(v, ElementsAre("a", "b", "c")); + } + + { + // Same as above, but using std::string + std::vector<std::string> v = absl::StrSplit("a,b,c", ','); + EXPECT_THAT(v, ElementsAre("a", "b", "c")); + + // Equivalent to... + using absl::ByChar; + v = absl::StrSplit("a,b,c", ByChar(',')); + EXPECT_THAT(v, ElementsAre("a", "b", "c")); + } + + { + // Uses the Literal std::string "=>" as the delimiter. + const std::vector<std::string> v = absl::StrSplit("a=>b=>c", "=>"); + EXPECT_THAT(v, ElementsAre("a", "b", "c")); + } + + { + // The substrings are returned as string_views, eliminating copying. + std::vector<absl::string_view> v = absl::StrSplit("a,b,c", ','); + EXPECT_THAT(v, ElementsAre("a", "b", "c")); + } + + { + // Leading and trailing empty substrings. + std::vector<std::string> v = absl::StrSplit(",a,b,c,", ','); + EXPECT_THAT(v, ElementsAre("", "a", "b", "c", "")); + } + + { + // Splits on a delimiter that is not found. + std::vector<std::string> v = absl::StrSplit("abc", ','); + EXPECT_THAT(v, ElementsAre("abc")); + } + + { + // Splits the input std::string into individual characters by using an empty + // std::string as the delimiter. + std::vector<std::string> v = absl::StrSplit("abc", ""); + EXPECT_THAT(v, ElementsAre("a", "b", "c")); + } + + { + // Splits std::string data with embedded NUL characters, using NUL as the + // delimiter. A simple delimiter of "\0" doesn't work because strlen() will + // say that's the empty std::string when constructing the absl::string_view + // delimiter. Instead, a non-empty std::string containing NUL can be used as the + // delimiter. + std::string embedded_nulls("a\0b\0c", 5); + std::string null_delim("\0", 1); + std::vector<std::string> v = absl::StrSplit(embedded_nulls, null_delim); + EXPECT_THAT(v, ElementsAre("a", "b", "c")); + } + + { + // Stores first two split strings as the members in a std::pair. + std::pair<std::string, std::string> p = absl::StrSplit("a,b,c", ','); + EXPECT_EQ("a", p.first); + EXPECT_EQ("b", p.second); + // "c" is omitted because std::pair can hold only two elements. + } + + { + // Results stored in std::set<std::string> + std::set<std::string> v = absl::StrSplit("a,b,c,a,b,c,a,b,c", ','); + EXPECT_THAT(v, ElementsAre("a", "b", "c")); + } + + { + // Uses a non-const char* delimiter. + char a[] = ","; + char* d = a + 0; + std::vector<std::string> v = absl::StrSplit("a,b,c", d); + EXPECT_THAT(v, ElementsAre("a", "b", "c")); + } + + { + // Results split using either of , or ; + using absl::ByAnyChar; + std::vector<std::string> v = absl::StrSplit("a,b;c", ByAnyChar(",;")); + EXPECT_THAT(v, ElementsAre("a", "b", "c")); + } + + { + // Uses the SkipWhitespace predicate. + using absl::SkipWhitespace; + std::vector<std::string> v = absl::StrSplit(" a , ,,b,", ',', SkipWhitespace()); + EXPECT_THAT(v, ElementsAre(" a ", "b")); + } + + { + // Uses the ByLength delimiter. + using absl::ByLength; + std::vector<std::string> v = absl::StrSplit("abcdefg", ByLength(3)); + EXPECT_THAT(v, ElementsAre("abc", "def", "g")); + } + + { + // Different forms of initialization / conversion. + std::vector<std::string> v1 = absl::StrSplit("a,b,c", ','); + EXPECT_THAT(v1, ElementsAre("a", "b", "c")); + std::vector<std::string> v2(absl::StrSplit("a,b,c", ',')); + EXPECT_THAT(v2, ElementsAre("a", "b", "c")); + auto v3 = std::vector<std::string>(absl::StrSplit("a,b,c", ',')); + EXPECT_THAT(v3, ElementsAre("a", "b", "c")); + v3 = absl::StrSplit("a,b,c", ','); + EXPECT_THAT(v3, ElementsAre("a", "b", "c")); + } + + { + // Results stored in a std::map. + std::map<std::string, std::string> m = absl::StrSplit("a,1,b,2,a,3", ','); + EXPECT_EQ(2, m.size()); + EXPECT_EQ("3", m["a"]); + EXPECT_EQ("2", m["b"]); + } + + { + // Results stored in a std::multimap. + std::multimap<std::string, std::string> m = absl::StrSplit("a,1,b,2,a,3", ','); + EXPECT_EQ(3, m.size()); + auto it = m.find("a"); + EXPECT_EQ("1", it->second); + ++it; + EXPECT_EQ("3", it->second); + it = m.find("b"); + EXPECT_EQ("2", it->second); + } + + { + // Demonstrates use in a range-based for loop in C++11. + std::string s = "x,x,x,x,x,x,x"; + for (absl::string_view sp : absl::StrSplit(s, ',')) { + EXPECT_EQ("x", sp); + } + } + + { + // Demonstrates use with a Predicate in a range-based for loop. + using absl::SkipWhitespace; + std::string s = " ,x,,x,,x,x,x,,"; + for (absl::string_view sp : absl::StrSplit(s, ',', SkipWhitespace())) { + EXPECT_EQ("x", sp); + } + } + + { + // Demonstrates a "smart" split to std::map using two separate calls to + // absl::StrSplit. One call to split the records, and another call to split + // the keys and values. This also uses the Limit delimiter so that the + // std::string "a=b=c" will split to "a" -> "b=c". + std::map<std::string, std::string> m; + for (absl::string_view sp : absl::StrSplit("a=b=c,d=e,f=,g", ',')) { + m.insert(absl::StrSplit(sp, absl::MaxSplits('=', 1))); + } + EXPECT_EQ("b=c", m.find("a")->second); + EXPECT_EQ("e", m.find("d")->second); + EXPECT_EQ("", m.find("f")->second); + EXPECT_EQ("", m.find("g")->second); + } +} + +// +// Tests for SplitIterator +// + +TEST(SplitIterator, Basics) { + auto splitter = absl::StrSplit("a,b", ','); + auto it = splitter.begin(); + auto end = splitter.end(); + + EXPECT_NE(it, end); + EXPECT_EQ("a", *it); // tests dereference + ++it; // tests preincrement + EXPECT_NE(it, end); + EXPECT_EQ("b", std::string(it->data(), it->size())); // tests dereference as ptr + it++; // tests postincrement + EXPECT_EQ(it, end); +} + +// Simple Predicate to skip a particular std::string. +class Skip { + public: + explicit Skip(const std::string& s) : s_(s) {} + bool operator()(absl::string_view sp) { return sp != s_; } + + private: + std::string s_; +}; + +TEST(SplitIterator, Predicate) { + auto splitter = absl::StrSplit("a,b,c", ',', Skip("b")); + auto it = splitter.begin(); + auto end = splitter.end(); + + EXPECT_NE(it, end); + EXPECT_EQ("a", *it); // tests dereference + ++it; // tests preincrement -- "b" should be skipped here. + EXPECT_NE(it, end); + EXPECT_EQ("c", std::string(it->data(), it->size())); // tests dereference as ptr + it++; // tests postincrement + EXPECT_EQ(it, end); +} + +TEST(SplitIterator, EdgeCases) { + // Expected input and output, assuming a delimiter of ',' + struct { + std::string in; + std::vector<std::string> expect; + } specs[] = { + {"", {""}}, + {"foo", {"foo"}}, + {",", {"", ""}}, + {",foo", {"", "foo"}}, + {"foo,", {"foo", ""}}, + {",foo,", {"", "foo", ""}}, + {"foo,bar", {"foo", "bar"}}, + }; + + for (const auto& spec : specs) { + SCOPED_TRACE(spec.in); + auto splitter = absl::StrSplit(spec.in, ','); + auto it = splitter.begin(); + auto end = splitter.end(); + for (const auto& expected : spec.expect) { + EXPECT_NE(it, end); + EXPECT_EQ(expected, *it++); + } + EXPECT_EQ(it, end); + } +} + +TEST(Splitter, Const) { + const auto splitter = absl::StrSplit("a,b,c", ','); + EXPECT_THAT(splitter, ElementsAre("a", "b", "c")); +} + +TEST(Split, EmptyAndNull) { + // Attention: Splitting a null absl::string_view is different than splitting + // an empty absl::string_view even though both string_views are considered + // equal. This behavior is likely surprising and undesirable. However, to + // maintain backward compatibility, there is a small "hack" in + // str_split_internal.h that preserves this behavior. If that behavior is ever + // changed/fixed, this test will need to be updated. + EXPECT_THAT(absl::StrSplit(absl::string_view(""), '-'), ElementsAre("")); + EXPECT_THAT(absl::StrSplit(absl::string_view(), '-'), ElementsAre()); +} + +TEST(SplitIterator, EqualityAsEndCondition) { + auto splitter = absl::StrSplit("a,b,c", ','); + auto it = splitter.begin(); + auto it2 = it; + + // Increments it2 twice to point to "c" in the input text. + ++it2; + ++it2; + EXPECT_EQ("c", *it2); + + // This test uses a non-end SplitIterator as the terminating condition in a + // for loop. This relies on SplitIterator equality for non-end SplitIterators + // working correctly. At this point it2 points to "c", and we use that as the + // "end" condition in this test. + std::vector<absl::string_view> v; + for (; it != it2; ++it) { + v.push_back(*it); + } + EXPECT_THAT(v, ElementsAre("a", "b")); +} + +// +// Tests for Splitter +// + +TEST(Splitter, RangeIterators) { + auto splitter = absl::StrSplit("a,b,c", ','); + std::vector<absl::string_view> output; + for (const absl::string_view p : splitter) { + output.push_back(p); + } + EXPECT_THAT(output, ElementsAre("a", "b", "c")); +} + +// Some template functions for use in testing conversion operators +template <typename ContainerType, typename Splitter> +void TestConversionOperator(const Splitter& splitter) { + ContainerType output = splitter; + EXPECT_THAT(output, UnorderedElementsAre("a", "b", "c", "d")); +} + +template <typename MapType, typename Splitter> +void TestMapConversionOperator(const Splitter& splitter) { + MapType m = splitter; + EXPECT_THAT(m, UnorderedElementsAre(Pair("a", "b"), Pair("c", "d"))); +} + +template <typename FirstType, typename SecondType, typename Splitter> +void TestPairConversionOperator(const Splitter& splitter) { + std::pair<FirstType, SecondType> p = splitter; + EXPECT_EQ(p, (std::pair<FirstType, SecondType>("a", "b"))); +} + +TEST(Splitter, ConversionOperator) { + auto splitter = absl::StrSplit("a,b,c,d", ','); + + TestConversionOperator<std::vector<absl::string_view>>(splitter); + TestConversionOperator<std::vector<std::string>>(splitter); + TestConversionOperator<std::list<absl::string_view>>(splitter); + TestConversionOperator<std::list<std::string>>(splitter); + TestConversionOperator<std::deque<absl::string_view>>(splitter); + TestConversionOperator<std::deque<std::string>>(splitter); + TestConversionOperator<std::set<absl::string_view>>(splitter); + TestConversionOperator<std::set<std::string>>(splitter); + TestConversionOperator<std::multiset<absl::string_view>>(splitter); + TestConversionOperator<std::multiset<std::string>>(splitter); + TestConversionOperator<std::unordered_set<std::string>>(splitter); + + // Tests conversion to map-like objects. + + TestMapConversionOperator<std::map<absl::string_view, absl::string_view>>( + splitter); + TestMapConversionOperator<std::map<absl::string_view, std::string>>(splitter); + TestMapConversionOperator<std::map<std::string, absl::string_view>>(splitter); + TestMapConversionOperator<std::map<std::string, std::string>>(splitter); + TestMapConversionOperator< + std::multimap<absl::string_view, absl::string_view>>(splitter); + TestMapConversionOperator<std::multimap<absl::string_view, std::string>>(splitter); + TestMapConversionOperator<std::multimap<std::string, absl::string_view>>(splitter); + TestMapConversionOperator<std::multimap<std::string, std::string>>(splitter); + TestMapConversionOperator<std::unordered_map<std::string, std::string>>(splitter); + + // Tests conversion to std::pair + + TestPairConversionOperator<absl::string_view, absl::string_view>(splitter); + TestPairConversionOperator<absl::string_view, std::string>(splitter); + TestPairConversionOperator<std::string, absl::string_view>(splitter); + TestPairConversionOperator<std::string, std::string>(splitter); +} + +// A few additional tests for conversion to std::pair. This conversion is +// different from others because a std::pair always has exactly two elements: +// .first and .second. The split has to work even when the split has +// less-than, equal-to, and more-than 2 strings. +TEST(Splitter, ToPair) { + { + // Empty std::string + std::pair<std::string, std::string> p = absl::StrSplit("", ','); + EXPECT_EQ("", p.first); + EXPECT_EQ("", p.second); + } + + { + // Only first + std::pair<std::string, std::string> p = absl::StrSplit("a", ','); + EXPECT_EQ("a", p.first); + EXPECT_EQ("", p.second); + } + + { + // Only second + std::pair<std::string, std::string> p = absl::StrSplit(",b", ','); + EXPECT_EQ("", p.first); + EXPECT_EQ("b", p.second); + } + + { + // First and second. + std::pair<std::string, std::string> p = absl::StrSplit("a,b", ','); + EXPECT_EQ("a", p.first); + EXPECT_EQ("b", p.second); + } + + { + // First and second and then more stuff that will be ignored. + std::pair<std::string, std::string> p = absl::StrSplit("a,b,c", ','); + EXPECT_EQ("a", p.first); + EXPECT_EQ("b", p.second); + // "c" is omitted. + } +} + +TEST(Splitter, Predicates) { + static const char kTestChars[] = ",a, ,b,"; + using absl::AllowEmpty; + using absl::SkipEmpty; + using absl::SkipWhitespace; + + { + // No predicate. Does not skip empties. + auto splitter = absl::StrSplit(kTestChars, ','); + std::vector<std::string> v = splitter; + EXPECT_THAT(v, ElementsAre("", "a", " ", "b", "")); + } + + { + // Allows empty strings. Same behavior as no predicate at all. + auto splitter = absl::StrSplit(kTestChars, ',', AllowEmpty()); + std::vector<std::string> v_allowempty = splitter; + EXPECT_THAT(v_allowempty, ElementsAre("", "a", " ", "b", "")); + + // Ensures AllowEmpty equals the behavior with no predicate. + auto splitter_nopredicate = absl::StrSplit(kTestChars, ','); + std::vector<std::string> v_nopredicate = splitter_nopredicate; + EXPECT_EQ(v_allowempty, v_nopredicate); + } + + { + // Skips empty strings. + auto splitter = absl::StrSplit(kTestChars, ',', SkipEmpty()); + std::vector<std::string> v = splitter; + EXPECT_THAT(v, ElementsAre("a", " ", "b")); + } + + { + // Skips empty and all-whitespace strings. + auto splitter = absl::StrSplit(kTestChars, ',', SkipWhitespace()); + std::vector<std::string> v = splitter; + EXPECT_THAT(v, ElementsAre("a", "b")); + } +} + +// +// Tests for StrSplit() +// + +TEST(Split, Basics) { + { + // Doesn't really do anything useful because the return value is ignored, + // but it should work. + absl::StrSplit("a,b,c", ','); + } + + { + std::vector<absl::string_view> v = absl::StrSplit("a,b,c", ','); + EXPECT_THAT(v, ElementsAre("a", "b", "c")); + } + + { + std::vector<std::string> v = absl::StrSplit("a,b,c", ','); + EXPECT_THAT(v, ElementsAre("a", "b", "c")); + } + + { + // Ensures that assignment works. This requires a little extra work with + // C++11 because of overloads with initializer_list. + std::vector<std::string> v; + v = absl::StrSplit("a,b,c", ','); + + EXPECT_THAT(v, ElementsAre("a", "b", "c")); + std::map<std::string, std::string> m; + m = absl::StrSplit("a,b,c", ','); + EXPECT_EQ(2, m.size()); + std::unordered_map<std::string, std::string> hm; + hm = absl::StrSplit("a,b,c", ','); + EXPECT_EQ(2, hm.size()); + } +} + +absl::string_view ReturnStringView() { return "Hello World"; } +const char* ReturnConstCharP() { return "Hello World"; } +char* ReturnCharP() { return const_cast<char*>("Hello World"); } + +TEST(Split, AcceptsCertainTemporaries) { + std::vector<std::string> v; + v = absl::StrSplit(ReturnStringView(), ' '); + EXPECT_THAT(v, ElementsAre("Hello", "World")); + v = absl::StrSplit(ReturnConstCharP(), ' '); + EXPECT_THAT(v, ElementsAre("Hello", "World")); + v = absl::StrSplit(ReturnCharP(), ' '); + EXPECT_THAT(v, ElementsAre("Hello", "World")); +} + +TEST(Split, Temporary) { + // Use a std::string longer than the small-std::string-optimization length, so that when + // the temporary is destroyed, if the splitter keeps a reference to the + // std::string's contents, it'll reference freed memory instead of just dead + // on-stack memory. + const char input[] = "a,b,c,d,e,f,g,h,i,j,k,l,m,n,o,p,q,r,s,t,u"; + EXPECT_LT(sizeof(std::string), ABSL_ARRAYSIZE(input)) + << "Input should be larger than fits on the stack."; + + // This happens more often in C++11 as part of a range-based for loop. + auto splitter = absl::StrSplit(std::string(input), ','); + std::string expected = "a"; + for (absl::string_view letter : splitter) { + EXPECT_EQ(expected, letter); + ++expected[0]; + } + EXPECT_EQ("v", expected); + + // This happens more often in C++11 as part of a range-based for loop. + auto std_splitter = absl::StrSplit(std::string(input), ','); + expected = "a"; + for (absl::string_view letter : std_splitter) { + EXPECT_EQ(expected, letter); + ++expected[0]; + } + EXPECT_EQ("v", expected); +} + +template <typename T> +static std::unique_ptr<T> CopyToHeap(const T& value) { + return std::unique_ptr<T>(new T(value)); +} + +TEST(Split, LvalueCaptureIsCopyable) { + std::string input = "a,b"; + auto heap_splitter = CopyToHeap(absl::StrSplit(input, ',')); + auto stack_splitter = *heap_splitter; + heap_splitter.reset(); + std::vector<std::string> result = stack_splitter; + EXPECT_THAT(result, testing::ElementsAre("a", "b")); +} + +TEST(Split, TemporaryCaptureIsCopyable) { + auto heap_splitter = CopyToHeap(absl::StrSplit(std::string("a,b"), ',')); + auto stack_splitter = *heap_splitter; + heap_splitter.reset(); + std::vector<std::string> result = stack_splitter; + EXPECT_THAT(result, testing::ElementsAre("a", "b")); +} + +TEST(Split, SplitterIsCopyableAndMoveable) { + auto a = absl::StrSplit("foo", '-'); + + // Ensures that the following expressions compile. + auto b = a; // Copy construct + auto c = std::move(a); // Move construct + b = c; // Copy assign + c = std::move(b); // Move assign + + EXPECT_THAT(c, ElementsAre("foo")); +} + +TEST(Split, StringDelimiter) { + { + std::vector<absl::string_view> v = absl::StrSplit("a,b", ','); + EXPECT_THAT(v, ElementsAre("a", "b")); + } + + { + std::vector<absl::string_view> v = absl::StrSplit("a,b", std::string(",")); + EXPECT_THAT(v, ElementsAre("a", "b")); + } + + { + std::vector<absl::string_view> v = + absl::StrSplit("a,b", absl::string_view(",")); + EXPECT_THAT(v, ElementsAre("a", "b")); + } +} + +TEST(Split, UTF8) { + // Tests splitting utf8 strings and utf8 delimiters. + std::string utf8_string = u8"\u03BA\u1F79\u03C3\u03BC\u03B5"; + { + // A utf8 input std::string with an ascii delimiter. + std::string to_split = "a," + utf8_string; + std::vector<absl::string_view> v = absl::StrSplit(to_split, ','); + EXPECT_THAT(v, ElementsAre("a", utf8_string)); + } + + { + // A utf8 input std::string and a utf8 delimiter. + std::string to_split = "a," + utf8_string + ",b"; + std::string unicode_delimiter = "," + utf8_string + ","; + std::vector<absl::string_view> v = + absl::StrSplit(to_split, unicode_delimiter); + EXPECT_THAT(v, ElementsAre("a", "b")); + } + + { + // A utf8 input std::string and ByAnyChar with ascii chars. + std::vector<absl::string_view> v = + absl::StrSplit(u8"Foo h\u00E4llo th\u4E1Ere", absl::ByAnyChar(" \t")); + EXPECT_THAT(v, ElementsAre("Foo", u8"h\u00E4llo", u8"th\u4E1Ere")); + } +} + +TEST(Split, EmptyStringDelimiter) { + { + std::vector<std::string> v = absl::StrSplit("", ""); + EXPECT_THAT(v, ElementsAre("")); + } + + { + std::vector<std::string> v = absl::StrSplit("a", ""); + EXPECT_THAT(v, ElementsAre("a")); + } + + { + std::vector<std::string> v = absl::StrSplit("ab", ""); + EXPECT_THAT(v, ElementsAre("a", "b")); + } + + { + std::vector<std::string> v = absl::StrSplit("a b", ""); + EXPECT_THAT(v, ElementsAre("a", " ", "b")); + } +} + +TEST(Split, SubstrDelimiter) { + std::vector<absl::string_view> results; + absl::string_view delim("//"); + + results = absl::StrSplit("", delim); + EXPECT_THAT(results, ElementsAre("")); + + results = absl::StrSplit("//", delim); + EXPECT_THAT(results, ElementsAre("", "")); + + results = absl::StrSplit("ab", delim); + EXPECT_THAT(results, ElementsAre("ab")); + + results = absl::StrSplit("ab//", delim); + EXPECT_THAT(results, ElementsAre("ab", "")); + + results = absl::StrSplit("ab/", delim); + EXPECT_THAT(results, ElementsAre("ab/")); + + results = absl::StrSplit("a/b", delim); + EXPECT_THAT(results, ElementsAre("a/b")); + + results = absl::StrSplit("a//b", delim); + EXPECT_THAT(results, ElementsAre("a", "b")); + + results = absl::StrSplit("a///b", delim); + EXPECT_THAT(results, ElementsAre("a", "/b")); + + results = absl::StrSplit("a////b", delim); + EXPECT_THAT(results, ElementsAre("a", "", "b")); +} + +TEST(Split, EmptyResults) { + std::vector<absl::string_view> results; + + results = absl::StrSplit("", '#'); + EXPECT_THAT(results, ElementsAre("")); + + results = absl::StrSplit("#", '#'); + EXPECT_THAT(results, ElementsAre("", "")); + + results = absl::StrSplit("#cd", '#'); + EXPECT_THAT(results, ElementsAre("", "cd")); + + results = absl::StrSplit("ab#cd#", '#'); + EXPECT_THAT(results, ElementsAre("ab", "cd", "")); + + results = absl::StrSplit("ab##cd", '#'); + EXPECT_THAT(results, ElementsAre("ab", "", "cd")); + + results = absl::StrSplit("ab##", '#'); + EXPECT_THAT(results, ElementsAre("ab", "", "")); + + results = absl::StrSplit("ab#ab#", '#'); + EXPECT_THAT(results, ElementsAre("ab", "ab", "")); + + results = absl::StrSplit("aaaa", 'a'); + EXPECT_THAT(results, ElementsAre("", "", "", "", "")); + + results = absl::StrSplit("", '#', absl::SkipEmpty()); + EXPECT_THAT(results, ElementsAre()); +} + +template <typename Delimiter> +static bool IsFoundAtStartingPos(absl::string_view text, Delimiter d, + size_t starting_pos, int expected_pos) { + absl::string_view found = d.Find(text, starting_pos); + return found.data() != text.end() && + expected_pos == found.data() - text.data(); +} + +// Helper function for testing Delimiter objects. Returns true if the given +// Delimiter is found in the given std::string at the given position. This function +// tests two cases: +// 1. The actual text given, staring at position 0 +// 2. The text given with leading padding that should be ignored +template <typename Delimiter> +static bool IsFoundAt(absl::string_view text, Delimiter d, int expected_pos) { + const std::string leading_text = ",x,y,z,"; + return IsFoundAtStartingPos(text, d, 0, expected_pos) && + IsFoundAtStartingPos(leading_text + std::string(text), d, + leading_text.length(), + expected_pos + leading_text.length()); +} + +// +// Tests for Literal +// + +// Tests using any delimiter that represents a single comma. +template <typename Delimiter> +void TestComma(Delimiter d) { + EXPECT_TRUE(IsFoundAt(",", d, 0)); + EXPECT_TRUE(IsFoundAt("a,", d, 1)); + EXPECT_TRUE(IsFoundAt(",b", d, 0)); + EXPECT_TRUE(IsFoundAt("a,b", d, 1)); + EXPECT_TRUE(IsFoundAt("a,b,", d, 1)); + EXPECT_TRUE(IsFoundAt("a,b,c", d, 1)); + EXPECT_FALSE(IsFoundAt("", d, -1)); + EXPECT_FALSE(IsFoundAt(" ", d, -1)); + EXPECT_FALSE(IsFoundAt("a", d, -1)); + EXPECT_FALSE(IsFoundAt("a b c", d, -1)); + EXPECT_FALSE(IsFoundAt("a;b;c", d, -1)); + EXPECT_FALSE(IsFoundAt(";", d, -1)); +} + +TEST(Delimiter, Literal) { + using absl::ByString; + TestComma(ByString(",")); + + // Works as named variable. + ByString comma_string(","); + TestComma(comma_string); + + // The first occurrence of empty std::string ("") in a std::string is at position 0. + // There is a test below that demonstrates this for absl::string_view::find(). + // If the ByString delimiter returned position 0 for this, there would + // be an infinite loop in the SplitIterator code. To avoid this, empty std::string + // is a special case in that it always returns the item at position 1. + absl::string_view abc("abc"); + EXPECT_EQ(0, abc.find("")); // "" is found at position 0 + ByString empty(""); + EXPECT_FALSE(IsFoundAt("", empty, 0)); + EXPECT_FALSE(IsFoundAt("a", empty, 0)); + EXPECT_TRUE(IsFoundAt("ab", empty, 1)); + EXPECT_TRUE(IsFoundAt("abc", empty, 1)); +} + +TEST(Split, ByChar) { + using absl::ByChar; + TestComma(ByChar(',')); + + // Works as named variable. + ByChar comma_char(','); + TestComma(comma_char); +} + +// +// Tests for ByAnyChar +// + +TEST(Delimiter, ByAnyChar) { + using absl::ByAnyChar; + ByAnyChar one_delim(","); + // Found + EXPECT_TRUE(IsFoundAt(",", one_delim, 0)); + EXPECT_TRUE(IsFoundAt("a,", one_delim, 1)); + EXPECT_TRUE(IsFoundAt("a,b", one_delim, 1)); + EXPECT_TRUE(IsFoundAt(",b", one_delim, 0)); + // Not found + EXPECT_FALSE(IsFoundAt("", one_delim, -1)); + EXPECT_FALSE(IsFoundAt(" ", one_delim, -1)); + EXPECT_FALSE(IsFoundAt("a", one_delim, -1)); + EXPECT_FALSE(IsFoundAt("a;b;c", one_delim, -1)); + EXPECT_FALSE(IsFoundAt(";", one_delim, -1)); + + ByAnyChar two_delims(",;"); + // Found + EXPECT_TRUE(IsFoundAt(",", two_delims, 0)); + EXPECT_TRUE(IsFoundAt(";", two_delims, 0)); + EXPECT_TRUE(IsFoundAt(",;", two_delims, 0)); + EXPECT_TRUE(IsFoundAt(";,", two_delims, 0)); + EXPECT_TRUE(IsFoundAt(",;b", two_delims, 0)); + EXPECT_TRUE(IsFoundAt(";,b", two_delims, 0)); + EXPECT_TRUE(IsFoundAt("a;,", two_delims, 1)); + EXPECT_TRUE(IsFoundAt("a,;", two_delims, 1)); + EXPECT_TRUE(IsFoundAt("a;,b", two_delims, 1)); + EXPECT_TRUE(IsFoundAt("a,;b", two_delims, 1)); + // Not found + EXPECT_FALSE(IsFoundAt("", two_delims, -1)); + EXPECT_FALSE(IsFoundAt(" ", two_delims, -1)); + EXPECT_FALSE(IsFoundAt("a", two_delims, -1)); + EXPECT_FALSE(IsFoundAt("a=b=c", two_delims, -1)); + EXPECT_FALSE(IsFoundAt("=", two_delims, -1)); + + // ByAnyChar behaves just like ByString when given a delimiter of empty + // std::string. That is, it always returns a zero-length absl::string_view + // referring to the item at position 1, not position 0. + ByAnyChar empty(""); + EXPECT_FALSE(IsFoundAt("", empty, 0)); + EXPECT_FALSE(IsFoundAt("a", empty, 0)); + EXPECT_TRUE(IsFoundAt("ab", empty, 1)); + EXPECT_TRUE(IsFoundAt("abc", empty, 1)); +} + +// +// Tests for ByLength +// + +TEST(Delimiter, ByLength) { + using absl::ByLength; + + ByLength four_char_delim(4); + + // Found + EXPECT_TRUE(IsFoundAt("abcde", four_char_delim, 4)); + EXPECT_TRUE(IsFoundAt("abcdefghijklmnopqrstuvwxyz", four_char_delim, 4)); + EXPECT_TRUE(IsFoundAt("a b,c\nd", four_char_delim, 4)); + // Not found + EXPECT_FALSE(IsFoundAt("", four_char_delim, 0)); + EXPECT_FALSE(IsFoundAt("a", four_char_delim, 0)); + EXPECT_FALSE(IsFoundAt("ab", four_char_delim, 0)); + EXPECT_FALSE(IsFoundAt("abc", four_char_delim, 0)); + EXPECT_FALSE(IsFoundAt("abcd", four_char_delim, 0)); +} + +TEST(Split, WorksWithLargeStrings) { + if (sizeof(size_t) > 4) { + std::string s((uint32_t{1} << 31) + 1, 'x'); // 2G + 1 byte + s.back() = '-'; + std::vector<absl::string_view> v = absl::StrSplit(s, '-'); + EXPECT_EQ(2, v.size()); + // The first element will contain 2G of 'x's. + // testing::StartsWith is too slow with a 2G std::string. + EXPECT_EQ('x', v[0][0]); + EXPECT_EQ('x', v[0][1]); + EXPECT_EQ('x', v[0][3]); + EXPECT_EQ("", v[1]); + } +} + +TEST(SplitInternalTest, TypeTraits) { + EXPECT_FALSE(absl::strings_internal::HasMappedType<int>::value); + EXPECT_TRUE( + (absl::strings_internal::HasMappedType<std::map<int, int>>::value)); + EXPECT_FALSE(absl::strings_internal::HasValueType<int>::value); + EXPECT_TRUE( + (absl::strings_internal::HasValueType<std::map<int, int>>::value)); + EXPECT_FALSE(absl::strings_internal::HasConstIterator<int>::value); + EXPECT_TRUE( + (absl::strings_internal::HasConstIterator<std::map<int, int>>::value)); + EXPECT_FALSE(absl::strings_internal::IsInitializerList<int>::value); + EXPECT_TRUE((absl::strings_internal::IsInitializerList< + std::initializer_list<int>>::value)); +} + +} // namespace
http://git-wip-us.apache.org/repos/asf/marmotta/blob/0eb556da/libraries/ostrich/backend/3rdparty/abseil/absl/strings/string_view.cc ---------------------------------------------------------------------- diff --git a/libraries/ostrich/backend/3rdparty/abseil/absl/strings/string_view.cc b/libraries/ostrich/backend/3rdparty/abseil/absl/strings/string_view.cc new file mode 100644 index 0000000..0e17295 --- /dev/null +++ b/libraries/ostrich/backend/3rdparty/abseil/absl/strings/string_view.cc @@ -0,0 +1,247 @@ +// Copyright 2017 The Abseil Authors. +// +// 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 "absl/strings/string_view.h" + +#ifndef ABSL_HAVE_STD_STRING_VIEW + +#include <algorithm> +#include <climits> +#include <cstring> +#include <ostream> + +#include "absl/strings/internal/memutil.h" +#include "absl/strings/internal/resize_uninitialized.h" +#include "absl/strings/match.h" + +namespace absl { + +namespace { +void WritePadding(std::ostream& o, size_t pad) { + char fill_buf[32]; + memset(fill_buf, o.fill(), sizeof(fill_buf)); + while (pad) { + size_t n = std::min(pad, sizeof(fill_buf)); + o.write(fill_buf, n); + pad -= n; + } +} + +class LookupTable { + public: + // For each character in wanted, sets the index corresponding + // to the ASCII code of that character. This is used by + // the find_.*_of methods below to tell whether or not a character is in + // the lookup table in constant time. + explicit LookupTable(string_view wanted) { + for (char c : wanted) { + table_[Index(c)] = true; + } + } + bool operator[](char c) const { return table_[Index(c)]; } + + private: + static unsigned char Index(char c) { return static_cast<unsigned char>(c); } + bool table_[UCHAR_MAX + 1] = {}; +}; + +} // namespace + +std::ostream& operator<<(std::ostream& o, string_view piece) { + std::ostream::sentry sentry(o); + if (sentry) { + size_t lpad = 0; + size_t rpad = 0; + if (static_cast<size_t>(o.width()) > piece.size()) { + size_t pad = o.width() - piece.size(); + if ((o.flags() & o.adjustfield) == o.left) { + rpad = pad; + } else { + lpad = pad; + } + } + if (lpad) WritePadding(o, lpad); + o.write(piece.data(), piece.size()); + if (rpad) WritePadding(o, rpad); + o.width(0); + } + return o; +} + +string_view::size_type string_view::copy(char* buf, size_type n, + size_type pos) const { + size_type ulen = length_; + assert(pos <= ulen); + size_type rlen = std::min(ulen - pos, n); + if (rlen > 0) { + const char* start = ptr_ + pos; + std::copy(start, start + rlen, buf); + } + return rlen; +} + +string_view::size_type string_view::find(string_view s, size_type pos) const + noexcept { + if (empty() || pos > length_) { + if (empty() && pos == 0 && s.empty()) return 0; + return npos; + } + const char* result = + strings_internal::memmatch(ptr_ + pos, length_ - pos, s.ptr_, s.length_); + return result ? result - ptr_ : npos; +} + +string_view::size_type string_view::find(char c, size_type pos) const noexcept { + if (empty() || pos >= length_) { + return npos; + } + const char* result = + static_cast<const char*>(memchr(ptr_ + pos, c, length_ - pos)); + return result != nullptr ? result - ptr_ : npos; +} + +string_view::size_type string_view::rfind(string_view s, size_type pos) const + noexcept { + if (length_ < s.length_) return npos; + if (s.empty()) return std::min(length_, pos); + const char* last = ptr_ + std::min(length_ - s.length_, pos) + s.length_; + const char* result = std::find_end(ptr_, last, s.ptr_, s.ptr_ + s.length_); + return result != last ? result - ptr_ : npos; +} + +// Search range is [0..pos] inclusive. If pos == npos, search everything. +string_view::size_type string_view::rfind(char c, size_type pos) const + noexcept { + // Note: memrchr() is not available on Windows. + if (empty()) return npos; + for (size_type i = std::min(pos, length_ - 1);; --i) { + if (ptr_[i] == c) { + return i; + } + if (i == 0) break; + } + return npos; +} + +string_view::size_type string_view::find_first_of(string_view s, + size_type pos) const + noexcept { + if (empty() || s.empty()) { + return npos; + } + // Avoid the cost of LookupTable() for a single-character search. + if (s.length_ == 1) return find_first_of(s.ptr_[0], pos); + LookupTable tbl(s); + for (size_type i = pos; i < length_; ++i) { + if (tbl[ptr_[i]]) { + return i; + } + } + return npos; +} + +string_view::size_type string_view::find_first_not_of(string_view s, + size_type pos) const + noexcept { + if (empty()) return npos; + // Avoid the cost of LookupTable() for a single-character search. + if (s.length_ == 1) return find_first_not_of(s.ptr_[0], pos); + LookupTable tbl(s); + for (size_type i = pos; i < length_; ++i) { + if (!tbl[ptr_[i]]) { + return i; + } + } + return npos; +} + +string_view::size_type string_view::find_first_not_of(char c, + size_type pos) const + noexcept { + if (empty()) return npos; + for (; pos < length_; ++pos) { + if (ptr_[pos] != c) { + return pos; + } + } + return npos; +} + +string_view::size_type string_view::find_last_of(string_view s, + size_type pos) const noexcept { + if (empty() || s.empty()) return npos; + // Avoid the cost of LookupTable() for a single-character search. + if (s.length_ == 1) return find_last_of(s.ptr_[0], pos); + LookupTable tbl(s); + for (size_type i = std::min(pos, length_ - 1);; --i) { + if (tbl[ptr_[i]]) { + return i; + } + if (i == 0) break; + } + return npos; +} + +string_view::size_type string_view::find_last_not_of(string_view s, + size_type pos) const + noexcept { + if (empty()) return npos; + size_type i = std::min(pos, length_ - 1); + if (s.empty()) return i; + // Avoid the cost of LookupTable() for a single-character search. + if (s.length_ == 1) return find_last_not_of(s.ptr_[0], pos); + LookupTable tbl(s); + for (;; --i) { + if (!tbl[ptr_[i]]) { + return i; + } + if (i == 0) break; + } + return npos; +} + +string_view::size_type string_view::find_last_not_of(char c, + size_type pos) const + noexcept { + if (empty()) return npos; + size_type i = std::min(pos, length_ - 1); + for (;; --i) { + if (ptr_[i] != c) { + return i; + } + if (i == 0) break; + } + return npos; +} + +// MSVC has non-standard behavior that implicitly creates definitions for static +// const members. These implicit definitions conflict with explicit out-of-class +// member definitions that are required by the C++ standard, resulting in +// LNK1169 "multiply defined" errors at link time. __declspec(selectany) asks +// MSVC to choose only one definition for the symbol it decorates. See details +// at http://msdn.microsoft.com/en-us/library/34h23df8(v=vs.100).aspx +#ifdef _MSC_VER +#define ABSL_STRING_VIEW_SELECTANY __declspec(selectany) +#else +#define ABSL_STRING_VIEW_SELECTANY +#endif + +ABSL_STRING_VIEW_SELECTANY +constexpr string_view::size_type string_view::npos; +ABSL_STRING_VIEW_SELECTANY +constexpr string_view::size_type string_view::kMaxSize; + +} // namespace absl + +#endif // ABSL_HAVE_STD_STRING_VIEW http://git-wip-us.apache.org/repos/asf/marmotta/blob/0eb556da/libraries/ostrich/backend/3rdparty/abseil/absl/strings/string_view.h ---------------------------------------------------------------------- diff --git a/libraries/ostrich/backend/3rdparty/abseil/absl/strings/string_view.h b/libraries/ostrich/backend/3rdparty/abseil/absl/strings/string_view.h new file mode 100644 index 0000000..9162bb3 --- /dev/null +++ b/libraries/ostrich/backend/3rdparty/abseil/absl/strings/string_view.h @@ -0,0 +1,570 @@ +// +// Copyright 2017 The Abseil Authors. +// +// 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. +// +// ----------------------------------------------------------------------------- +// File: string_view.h +// ----------------------------------------------------------------------------- +// +// This file contains the definition of the `absl::string_view` class. A +// `string_view` points to a contiguous span of characters, often part or all of +// another `std::string`, double-quoted std::string literal, character array, or even +// another `string_view`. +// +// This `absl::string_view` abstraction is designed to be a drop-in +// replacement for the C++17 `std::string_view` abstraction. +#ifndef ABSL_STRINGS_STRING_VIEW_H_ +#define ABSL_STRINGS_STRING_VIEW_H_ + +#include <algorithm> +#include "absl/base/config.h" + +#ifdef ABSL_HAVE_STD_STRING_VIEW + +#include <string_view> + +namespace absl { +using std::string_view; +}; + +#else // ABSL_HAVE_STD_STRING_VIEW + +#include <cassert> +#include <cstddef> +#include <cstring> +#include <iosfwd> +#include <iterator> +#include <limits> +#include <string> + +#include "absl/base/internal/throw_delegate.h" +#include "absl/base/macros.h" +#include "absl/base/port.h" + +namespace absl { + +// absl::string_view +// +// A `string_view` provides a lightweight view into the std::string data provided by +// a `std::string`, double-quoted std::string literal, character array, or even +// another `string_view`. A `string_view` does *not* own the std::string to which it +// points, and that data cannot be modified through the view. +// +// You can use `string_view` as a function or method parameter anywhere a +// parameter can receive a double-quoted std::string literal, `const char*`, +// `std::string`, or another `absl::string_view` argument with no need to copy +// the std::string data. Systematic use of `string_view` within function arguments +// reduces data copies and `strlen()` calls. +// +// Because of its small size, prefer passing `string_view` by value: +// +// void MyFunction(absl::string_view arg); +// +// If circumstances require, you may also pass one by const reference: +// +// void MyFunction(const absl::string_view& arg); // not preferred +// +// Passing by value generates slightly smaller code for many architectures. +// +// In either case, the source data of the `string_view` must outlive the +// `string_view` itself. +// +// A `string_view` is also suitable for local variables if you know that the +// lifetime of the underlying object is longer than the lifetime of your +// `string_view` variable. However, beware of binding a `string_view` to a +// temporary value: +// +// // BAD use of string_view: lifetime problem +// absl::string_view sv = obj.ReturnAString(); +// +// // GOOD use of string_view: str outlives sv +// std::string str = obj.ReturnAString(); +// absl::string_view sv = str; +// +// Due to lifetime issues, a `string_view` is sometimes a poor choice for a +// return value and usually a poor choice for a data member. If you do use a +// `string_view` this way, it is your responsibility to ensure that the object +// pointed to by the `string_view` outlives the `string_view`. +// +// A `string_view` may represent a whole std::string or just part of a std::string. For +// example, when splitting a std::string, `std::vector<absl::string_view>` is a +// natural data type for the output. +// +// +// When constructed from a source which is nul-terminated, the `string_view` +// itself will not include the nul-terminator unless a specific size (including +// the nul) is passed to the constructor. As a result, common idioms that work +// on nul-terminated strings do not work on `string_view` objects. If you write +// code that scans a `string_view`, you must check its length rather than test +// for nul, for example. Note, however, that nuls may still be embedded within +// a `string_view` explicitly. +// +// You may create a null `string_view` in two ways: +// +// absl::string_view sv(); +// absl::string_view sv(nullptr, 0); +// +// For the above, `sv.data() == nullptr`, `sv.length() == 0`, and +// `sv.empty() == true`. Also, if you create a `string_view` with a non-null +// pointer then `sv.data() != nullptr`. Thus, you can use `string_view()` to +// signal an undefined value that is different from other `string_view` values +// in a similar fashion to how `const char* p1 = nullptr;` is different from +// `const char* p2 = "";`. However, in practice, it is not recommended to rely +// on this behavior. +// +// Be careful not to confuse a null `string_view` with an empty one. A null +// `string_view` is an empty `string_view`, but some empty `string_view`s are +// not null. Prefer checking for emptiness over checking for null. +// +// There are many ways to create an empty string_view: +// +// const char* nullcp = nullptr; +// // string_view.size() will return 0 in all cases. +// absl::string_view(); +// absl::string_view(nullcp, 0); +// absl::string_view(""); +// absl::string_view("", 0); +// absl::string_view("abcdef", 0); +// absl::string_view("abcdef" + 6, 0); +// +// All empty `string_view` objects whether null or not, are equal: +// +// absl::string_view() == absl::string_view("", 0) +// absl::string_view(nullptr, 0) == absl:: string_view("abcdef"+6, 0) +class string_view { + public: + using traits_type = std::char_traits<char>; + using value_type = char; + using pointer = char*; + using const_pointer = const char*; + using reference = char&; + using const_reference = const char&; + using const_iterator = const char*; + using iterator = const_iterator; + using const_reverse_iterator = std::reverse_iterator<const_iterator>; + using reverse_iterator = const_reverse_iterator; + using size_type = size_t; + using difference_type = std::ptrdiff_t; + + static constexpr size_type npos = static_cast<size_type>(-1); + + // Null `string_view` constructor + constexpr string_view() noexcept : ptr_(nullptr), length_(0) {} + + // Implicit constructors + + template <typename Allocator> + string_view( // NOLINT(runtime/explicit) + const std::basic_string<char, std::char_traits<char>, Allocator>& + str) noexcept + : ptr_(str.data()), length_(CheckLengthInternal(str.size())) {} + + // Implicit constructor of a `string_view` from nul-terminated `str`. When + // accepting possibly null strings, use `absl::NullSafeStringView(str)` + // instead (see below). + constexpr string_view(const char* str) // NOLINT(runtime/explicit) + : ptr_(str), length_(CheckLengthInternal(StrLenInternal(str))) {} + + // Implicit constructor of a `string_view` from a `const char*` and length. + constexpr string_view(const char* data, size_type len) + : ptr_(data), length_(CheckLengthInternal(len)) {} + + // NOTE: Harmlessly omitted to work around gdb bug. + // constexpr string_view(const string_view&) noexcept = default; + // string_view& operator=(const string_view&) noexcept = default; + + // Iterators + + // string_view::begin() + // + // Returns an iterator pointing to the first character at the beginning of the + // `string_view`, or `end()` if the `string_view` is empty. + constexpr const_iterator begin() const noexcept { return ptr_; } + + // string_view::end() + // + // Returns an iterator pointing just beyond the last character at the end of + // the `string_view`. This iterator acts as a placeholder; attempting to + // access it results in undefined behavior. + constexpr const_iterator end() const noexcept { return ptr_ + length_; } + + // string_view::cbegin() + // + // Returns a const iterator pointing to the first character at the beginning + // of the `string_view`, or `end()` if the `string_view` is empty. + constexpr const_iterator cbegin() const noexcept { return begin(); } + + // string_view::cend() + // + // Returns a const iterator pointing just beyond the last character at the end + // of the `string_view`. This pointer acts as a placeholder; attempting to + // access its element results in undefined behavior. + constexpr const_iterator cend() const noexcept { return end(); } + + // string_view::rbegin() + // + // Returns a reverse iterator pointing to the last character at the end of the + // `string_view`, or `rend()` if the `string_view` is empty. + const_reverse_iterator rbegin() const noexcept { + return const_reverse_iterator(end()); + } + + // string_view::rend() + // + // Returns a reverse iterator pointing just before the first character at the + // beginning of the `string_view`. This pointer acts as a placeholder; + // attempting to access its element results in undefined behavior. + const_reverse_iterator rend() const noexcept { + return const_reverse_iterator(begin()); + } + + // string_view::crbegin() + // + // Returns a const reverse iterator pointing to the last character at the end + // of the `string_view`, or `crend()` if the `string_view` is empty. + const_reverse_iterator crbegin() const noexcept { return rbegin(); } + + // string_view::crend() + // + // Returns a const reverse iterator pointing just before the first character + // at the beginning of the `string_view`. This pointer acts as a placeholder; + // attempting to access its element results in undefined behavior. + const_reverse_iterator crend() const noexcept { return rend(); } + + // Capacity Utilities + + // string_view::size() + // + // Returns the number of characters in the `string_view`. + constexpr size_type size() const noexcept { + return length_; + } + + // string_view::length() + // + // Returns the number of characters in the `string_view`. Alias for `size()`. + constexpr size_type length() const noexcept { return size(); } + + // string_view::max_size() + // + // Returns the maximum number of characters the `string_view` can hold. + constexpr size_type max_size() const noexcept { return kMaxSize; } + + // string_view::empty() + // + // Checks if the `string_view` is empty (refers to no characters). + constexpr bool empty() const noexcept { return length_ == 0; } + + // std::string:view::operator[] + // + // Returns the ith element of an `string_view` using the array operator. + // Note that this operator does not perform any bounds checking. + constexpr const_reference operator[](size_type i) const { return ptr_[i]; } + + // string_view::front() + // + // Returns the first element of a `string_view`. + constexpr const_reference front() const { return ptr_[0]; } + + // string_view::back() + // + // Returns the last element of a `string_view`. + constexpr const_reference back() const { return ptr_[size() - 1]; } + + // string_view::data() + // + // Returns a pointer to the underlying character array (which is of course + // stored elsewhere). Note that `string_view::data()` may contain embedded nul + // characters, but the returned buffer may or may not be nul-terminated; + // therefore, do not pass `data()` to a routine that expects a nul-terminated + // std::string. + constexpr const_pointer data() const noexcept { return ptr_; } + + // Modifiers + + // string_view::remove_prefix() + // + // Removes the first `n` characters from the `string_view`. Note that the + // underlying std::string is not changed, only the view. + void remove_prefix(size_type n) { + assert(n <= length_); + ptr_ += n; + length_ -= n; + } + + // string_view::remove_suffix() + // + // Removes the last `n` characters from the `string_view`. Note that the + // underlying std::string is not changed, only the view. + void remove_suffix(size_type n) { + assert(n <= length_); + length_ -= n; + } + + // string_view::swap() + // + // Swaps this `string_view` with another `string_view`. + void swap(string_view& s) noexcept { + auto t = *this; + *this = s; + s = t; + } + + // Explicit conversion operators + + // Converts to `std::basic_string`. + template <typename A> + explicit operator std::basic_string<char, traits_type, A>() const { + if (!data()) return {}; + return std::basic_string<char, traits_type, A>(data(), size()); + } + + // string_view::copy() + // + // Copies the contents of the `string_view` at offset `pos` and length `n` + // into `buf`. + size_type copy(char* buf, size_type n, size_type pos = 0) const; + + // string_view::substr() + // + // Returns a "substring" of the `string_view` (at offset `pos` and length + // `n`) as another string_view. This function throws `std::out_of_bounds` if + // `pos > size'. + string_view substr(size_type pos, size_type n = npos) const { + if (ABSL_PREDICT_FALSE(pos > length_)) + base_internal::ThrowStdOutOfRange("absl::string_view::substr"); + n = std::min(n, length_ - pos); + return string_view(ptr_ + pos, n); + } + + // string_view::compare() + // + // Performs a lexicographical comparison between the `string_view` and + // another `absl::string_view), returning -1 if `this` is less than, 0 if + // `this` is equal to, and 1 if `this` is greater than the passed std::string + // view. Note that in the case of data equality, a further comparison is made + // on the respective sizes of the two `string_view`s to determine which is + // smaller, equal, or greater. + int compare(string_view x) const noexcept { + auto min_length = std::min(length_, x.length_); + if (min_length > 0) { + int r = memcmp(ptr_, x.ptr_, min_length); + if (r < 0) return -1; + if (r > 0) return 1; + } + if (length_ < x.length_) return -1; + if (length_ > x.length_) return 1; + return 0; + } + + // Overload of `string_view::compare()` for comparing a substring of the + // 'string_view` and another `absl::string_view`. + int compare(size_type pos1, size_type count1, string_view v) const { + return substr(pos1, count1).compare(v); + } + + // Overload of `string_view::compare()` for comparing a substring of the + // `string_view` and a substring of another `absl::string_view`. + int compare(size_type pos1, size_type count1, string_view v, size_type pos2, + size_type count2) const { + return substr(pos1, count1).compare(v.substr(pos2, count2)); + } + + // Overload of `string_view::compare()` for comparing a `string_view` and a + // a different C-style std::string `s`. + int compare(const char* s) const { return compare(string_view(s)); } + + // Overload of `string_view::compare()` for comparing a substring of the + // `string_view` and a different std::string C-style std::string `s`. + int compare(size_type pos1, size_type count1, const char* s) const { + return substr(pos1, count1).compare(string_view(s)); + } + + // Overload of `string_view::compare()` for comparing a substring of the + // `string_view` and a substring of a different C-style std::string `s`. + int compare(size_type pos1, size_type count1, const char* s, + size_type count2) const { + return substr(pos1, count1).compare(string_view(s, count2)); + } + + // Find Utilities + + // string_view::find() + // + // Finds the first occurrence of the substring `s` within the `string_view`, + // returning the position of the first character's match, or `npos` if no + // match was found. + size_type find(string_view s, size_type pos = 0) const noexcept; + + // Overload of `string_view::find()` for finding the given character `c` + // within the `string_view`. + size_type find(char c, size_type pos = 0) const noexcept; + + // string_view::rfind() + // + // Finds the last occurrence of a substring `s` within the `string_view`, + // returning the position of the first character's match, or `npos` if no + // match was found. + size_type rfind(string_view s, size_type pos = npos) const + noexcept; + + // Overload of `string_view::rfind()` for finding the last given character `c` + // within the `string_view`. + size_type rfind(char c, size_type pos = npos) const noexcept; + + // string_view::find_first_of() + // + // Finds the first occurrence of any of the characters in `s` within the + // `string_view`, returning the start position of the match, or `npos` if no + // match was found. + size_type find_first_of(string_view s, size_type pos = 0) const + noexcept; + + // Overload of `string_view::find_first_of()` for finding a character `c` + // within the `string_view`. + size_type find_first_of(char c, size_type pos = 0) const + noexcept { + return find(c, pos); + } + + // string_view::find_last_of() + // + // Finds the last occurrence of any of the characters in `s` within the + // `string_view`, returning the start position of the match, or `npos` if no + // match was found. + size_type find_last_of(string_view s, size_type pos = npos) const + noexcept; + + // Overload of `string_view::find_last_of()` for finding a character `c` + // within the `string_view`. + size_type find_last_of(char c, size_type pos = npos) const + noexcept { + return rfind(c, pos); + } + + // string_view::find_first_not_of() + // + // Finds the first occurrence of any of the characters not in `s` within the + // `string_view`, returning the start position of the first non-match, or + // `npos` if no non-match was found. + size_type find_first_not_of(string_view s, size_type pos = 0) const noexcept; + + // Overload of `string_view::find_first_not_of()` for finding a character + // that is not `c` within the `string_view`. + size_type find_first_not_of(char c, size_type pos = 0) const noexcept; + + // string_view::find_last_not_of() + // + // Finds the last occurrence of any of the characters not in `s` within the + // `string_view`, returning the start position of the last non-match, or + // `npos` if no non-match was found. + size_type find_last_not_of(string_view s, + size_type pos = npos) const noexcept; + + // Overload of `string_view::find_last_not_of()` for finding a character + // that is not `c` within the `string_view`. + size_type find_last_not_of(char c, size_type pos = npos) const + noexcept; + + private: + static constexpr size_type kMaxSize = + std::numeric_limits<difference_type>::max(); + + // check whether __builtin_strlen is provided by the compiler. + // GCC doesn't have __has_builtin() + // (https://gcc.gnu.org/bugzilla/show_bug.cgi?id=66970), + // but has __builtin_strlen according to + // https://gcc.gnu.org/onlinedocs/gcc-4.7.0/gcc/Other-Builtins.html. +#if ABSL_HAVE_BUILTIN(__builtin_strlen) || \ + (defined(__GNUC__) && !defined(__clang__)) + static constexpr size_type StrLenInternal(const char* str) { + return str ? __builtin_strlen(str) : 0; + } +#else + static constexpr size_type StrLenInternal(const char* str) { + return str ? strlen(str) : 0; + } +#endif + + static constexpr size_type CheckLengthInternal(size_type len) { + return ABSL_ASSERT(len <= kMaxSize), len; + } + + const char* ptr_; + size_type length_; +}; + +// This large function is defined inline so that in a fairly common case where +// one of the arguments is a literal, the compiler can elide a lot of the +// following comparisons. +inline bool operator==(string_view x, string_view y) noexcept { + auto len = x.size(); + if (len != y.size()) { + return false; + } + return x.data() == y.data() || len <= 0 || + memcmp(x.data(), y.data(), len) == 0; +} + +inline bool operator!=(string_view x, string_view y) noexcept { + return !(x == y); +} + +inline bool operator<(string_view x, string_view y) noexcept { + auto min_size = std::min(x.size(), y.size()); + const int r = min_size == 0 ? 0 : memcmp(x.data(), y.data(), min_size); + return (r < 0) || (r == 0 && x.size() < y.size()); +} + +inline bool operator>(string_view x, string_view y) noexcept { return y < x; } + +inline bool operator<=(string_view x, string_view y) noexcept { + return !(y < x); +} + +inline bool operator>=(string_view x, string_view y) noexcept { + return !(x < y); +} + +// IO Insertion Operator +std::ostream& operator<<(std::ostream& o, string_view piece); + +} // namespace absl + +#endif // ABSL_HAVE_STD_STRING_VIEW + +namespace absl { + +// ClippedSubstr() +// +// Like `s.substr(pos, n)`, but clips `pos` to an upper bound of `s.size()`. +// Provided because std::string_view::substr throws if `pos > size()` +inline string_view ClippedSubstr(string_view s, size_t pos, + size_t n = string_view::npos) { + pos = std::min(pos, static_cast<size_t>(s.size())); + return s.substr(pos, n); +} + +// NullSafeStringView() +// +// Creates an `absl::string_view` from a pointer `p` even if it's null-valued. +// This function should be used where an `absl::string_view` can be created from +// a possibly-null pointer. +inline string_view NullSafeStringView(const char* p) { + return p ? string_view(p) : string_view(); +} + +} // namespace absl + +#endif // ABSL_STRINGS_STRING_VIEW_H_
