kakoune/src/string_utils.cc
Maxime Coste 19e1be8e0d Make wrap_lines a lazy range view
Avoid the need to allocate a vector by using the ranges
framework.
2019-11-23 21:50:58 +11:00

438 lines
12 KiB
C++

#include "string_utils.hh"
#include "exception.hh"
#include "utf8_iterator.hh"
#include "unit_tests.hh"
#include <cstdio>
namespace Kakoune
{
String trim_indent(StringView str)
{
if (str.empty())
return {};
if (str[0_byte] == '\n')
str = str.substr(1_byte);
while (not str.empty() and is_blank(str.back()))
str = str.substr(0, str.length() - 1);
utf8::iterator it{str.begin(), str};
while (it != str.end() and is_horizontal_blank(*it))
it++;
const StringView indent{str.begin(), it.base()};
return accumulate(str | split_after<StringView>('\n') | transform([&](auto&& line) {
if (line == "\n")
return line;
else if (not prefix_match(line, indent))
throw runtime_error("inconsistent indentation in the string");
return line.substr(indent.length());
}), String{}, [](String& s, StringView l) -> decltype(auto) { return s += l; });
}
String escape(StringView str, StringView characters, char escape)
{
String res;
res.reserve(str.length());
auto cbeg = characters.begin(), cend = characters.end();
for (auto it = str.begin(), end = str.end(); it != end; )
{
auto next = std::find_first_of(it, end, cbeg, cend);
if (next != end)
{
res += StringView{it, next+1};
res.back() = escape;
res += *next;
it = next+1;
}
else
{
res += StringView{it, next};
break;
}
}
return res;
}
String unescape(StringView str, StringView characters, char escape)
{
String res;
res.reserve(str.length());
for (auto it = str.begin(), end = str.end(); it != end; )
{
auto next = std::find(it, end, escape);
if (next != end and next+1 != end and contains(characters, *(next+1)))
{
res += StringView{it, next+1};
res.back() = *(next+1);
it = next + 2;
}
else
{
res += StringView{it, next == end ? next : next + 1};
it = next == end ? next : next + 1;
}
}
return res;
}
String indent(StringView str, StringView indent)
{
String res;
res.reserve(str.length());
bool was_eol = true;
for (ByteCount i = 0; i < str.length(); ++i)
{
if (was_eol)
res += indent;
res += str[i];
was_eol = is_eol(str[i]);
}
return res;
}
String replace(StringView str, StringView substr, StringView replacement)
{
String res;
for (auto it = str.begin(); it != str.end(); )
{
auto match = std::search(it, str.end(), substr.begin(), substr.end());
res += StringView{it, match};
if (match == str.end())
break;
res += replacement;
it = match + (int)substr.length();
}
return res;
}
Optional<int> str_to_int_ifp(StringView str)
{
bool negative = not str.empty() and str[0] == '-';
if (negative)
str = str.substr(1_byte);
if (str.empty())
return {};
unsigned int res = 0;
for (auto c : str)
{
if (c < '0' or c > '9')
return {};
res = res * 10 + c - '0';
}
return negative ? -res : res;
}
int str_to_int(StringView str)
{
if (auto val = str_to_int_ifp(str))
return *val;
throw runtime_error{str + " is not a number"};
}
InplaceString<15> to_string(int val)
{
InplaceString<15> res;
res.m_length = sprintf(res.m_data, "%i", val);
return res;
}
InplaceString<15> to_string(unsigned val)
{
InplaceString<15> res;
res.m_length = sprintf(res.m_data, "%u", val);
return res;
}
InplaceString<23> to_string(long int val)
{
InplaceString<23> res;
res.m_length = sprintf(res.m_data, "%li", val);
return res;
}
InplaceString<23> to_string(long long int val)
{
InplaceString<23> res;
res.m_length = sprintf(res.m_data, "%lli", val);
return res;
}
InplaceString<23> to_string(unsigned long val)
{
InplaceString<23> res;
res.m_length = sprintf(res.m_data, "%lu", val);
return res;
}
InplaceString<23> to_string(Hex val)
{
InplaceString<23> res;
res.m_length = sprintf(res.m_data, "%zx", val.val);
return res;
}
InplaceString<23> to_string(float val)
{
InplaceString<23> res;
res.m_length = sprintf(res.m_data, "%f", val);
return res;
}
InplaceString<7> to_string(Codepoint c)
{
InplaceString<7> res;
char* ptr = res.m_data;
utf8::dump(ptr, c);
res.m_length = (int)(ptr - res.m_data);
return res;
}
bool subsequence_match(StringView str, StringView subseq)
{
auto it = str.begin();
for (auto& c : subseq)
{
if (it == str.end())
return false;
while (*it != c)
{
if (++it == str.end())
return false;
}
++it;
}
return true;
}
String expand_tabs(StringView line, ColumnCount tabstop, ColumnCount col)
{
String res;
res.reserve(line.length());
for (auto it = line.begin(), end = line.end(); it != end; )
{
if (*it == '\t')
{
ColumnCount end_col = (col / tabstop + 1) * tabstop;
res += String{' ', end_col - col};
col = end_col;
++it;
}
else
{
auto char_beg = it;
auto cp = utf8::read_codepoint(it, end);
res += {char_beg, it};
col += codepoint_width(cp);
}
}
return res;
}
WrapView::Iterator::Iterator(StringView text, ColumnCount max_width)
: m_remaining{text}, m_max_width{max_width}
{
if (max_width <= 0)
throw runtime_error("Invalid max width");
++*this;
}
WrapView::Iterator& WrapView::Iterator::operator++()
{
using Utf8It = utf8::iterator<const char*>;
Utf8It it{m_remaining.begin(), m_remaining};
Utf8It last_word_end = it;
while (it != m_remaining.end())
{
const CharCategories cat = categorize(*it, {'_'});
if (cat == CharCategories::EndOfLine)
{
m_current = StringView{m_remaining.begin(), it.base()};
m_remaining = StringView{(it+1).base(), m_remaining.end()};
return *this;
}
Utf8It word_end = it+1;
while (word_end != m_remaining.end() and categorize(*word_end, {'_'}) == cat)
++word_end;
if (word_end > m_remaining.begin() and
utf8::column_distance(m_remaining.begin(), word_end.base()) >= m_max_width)
{
auto line_end = last_word_end <= m_remaining.begin() ?
Utf8It{utf8::advance(m_remaining.begin(), m_remaining.end(), m_max_width), m_remaining}
: last_word_end;
m_current = StringView{m_remaining.begin(), line_end.base()};
while (line_end != m_remaining.end() and is_horizontal_blank(*line_end))
++line_end;
if (line_end != m_remaining.end() and *line_end == '\n')
++line_end;
m_remaining = StringView{line_end.base(), m_remaining.end()};
return *this;
}
if (cat == CharCategories::Word or cat == CharCategories::Punctuation)
last_word_end = word_end;
if (word_end > m_remaining.begin())
it = word_end;
}
m_current = m_remaining;
m_remaining = StringView{};
return *this;
}
template<typename AppendFunc>
void format_impl(StringView fmt, ArrayView<const StringView> params, AppendFunc append)
{
int implicitIndex = 0;
for (auto it = fmt.begin(), end = fmt.end(); it != end;)
{
auto opening = std::find(it, end, '{');
if (opening == end)
{
append(StringView{it, opening});
break;
}
else if (opening != it and *(opening-1) == '\\')
{
append(StringView{it, opening-1});
append('{');
it = opening + 1;
}
else
{
append(StringView{it, opening});
auto closing = std::find(opening, end, '}');
if (closing == end)
throw runtime_error("format string error, unclosed '{'");
const int index = (closing == opening + 1) ?
implicitIndex : str_to_int({opening+1, closing});
if (index >= params.size())
throw runtime_error("format string parameter index too big");
append(params[index]);
implicitIndex = index+1;
it = closing+1;
}
}
}
StringView format_to(ArrayView<char> buffer, StringView fmt, ArrayView<const StringView> params)
{
char* ptr = buffer.begin();
const char* end = buffer.end();
format_impl(fmt, params, [&](StringView s) mutable {
for (auto c : s)
{
if (ptr == end)
throw runtime_error("buffer is too small");
*ptr++ = c;
}
});
if (ptr == end)
throw runtime_error("buffer is too small");
*ptr = 0;
return { buffer.begin(), ptr };
}
String format(StringView fmt, ArrayView<const StringView> params)
{
ByteCount size = fmt.length();
for (auto& s : params) size += s.length();
String res;
res.reserve(size);
format_impl(fmt, params, [&](StringView s) { res += s; });
return res;
}
String double_up(StringView s, StringView characters)
{
String res;
auto pos = s.begin();
for (auto it = s.begin(), end = s.end(); it != end; ++it)
{
if (contains(characters, *it))
{
res += StringView{pos, it+1};
res += *it;
pos = it+1;
}
}
res += StringView{pos, s.end()};
return res;
}
UnitTest test_string{[]()
{
kak_assert(String("youpi ") + "matin" == "youpi matin");
auto wrapped = "wrap this paragraph\n respecting whitespaces and much_too_long_words" | wrap_at(16) | gather<Vector>();
kak_assert(wrapped.size() == 6);
kak_assert(wrapped[0] == "wrap this");
kak_assert(wrapped[1] == "paragraph");
kak_assert(wrapped[2] == " respecting");
kak_assert(wrapped[3] == "whitespaces and");
kak_assert(wrapped[4] == "much_too_long_wo");
kak_assert(wrapped[5] == "rds");
auto wrapped2 = "error: unknown type" | wrap_at(7) | gather<Vector>();
kak_assert(wrapped2.size() == 3);
kak_assert(wrapped2[0] == "error:");
kak_assert(wrapped2[1] == "unknown");
kak_assert(wrapped2[2] == "type");
kak_assert(trim_indent(" ") == "");
kak_assert(trim_indent("no-indent") == "no-indent");
kak_assert(trim_indent("\nno-indent") == "no-indent");
kak_assert(trim_indent("\n indent\n indent") == "indent\nindent");
kak_assert(trim_indent("\n indent\n indent") == "indent\n indent");
kak_assert(trim_indent("\n indent\n indent\n ") == "indent\nindent");
kak_expect_throw(runtime_error, trim_indent("\n indent\nno-indent"));
kak_assert(escape(R"(\youpi:matin:tchou\:)", ":\\", '\\') == R"(\\youpi\:matin\:tchou\\\:)");
kak_assert(unescape(R"(\\youpi\:matin\:tchou\\\:)", ":\\", '\\') == R"(\youpi:matin:tchou\:)");
kak_assert(prefix_match("tchou kanaky", "tchou"));
kak_assert(prefix_match("tchou kanaky", "tchou kanaky"));
kak_assert(prefix_match("tchou kanaky", "t"));
kak_assert(not prefix_match("tchou kanaky", "c"));
kak_assert(subsequence_match("tchou kanaky", "tknky"));
kak_assert(subsequence_match("tchou kanaky", "knk"));
kak_assert(subsequence_match("tchou kanaky", "tchou kanaky"));
kak_assert(not subsequence_match("tchou kanaky", "tchou kanaky"));
kak_assert(format("Youhou {1} {} {0} \\{}", 10, "hehe", 5) == "Youhou hehe 5 10 {}");
char buffer[20];
kak_assert(format_to(buffer, "Hey {}", 15) == "Hey 15");
kak_assert(str_to_int("5") == 5);
kak_assert(str_to_int(to_string(INT_MAX)) == INT_MAX);
kak_assert(str_to_int(to_string(INT_MIN)) == INT_MIN);
kak_assert(str_to_int("00") == 0);
kak_assert(str_to_int("-0") == 0);
kak_assert(double_up(R"('foo%"bar"')", "'\"%") == R"(''foo%%""bar""'')");
kak_assert(replace("tchou/tcha/tchi", "/", "!!") == "tchou!!tcha!!tchi");
}};
}