Move all non-core string code to string_utils.{hh,cc}

1 files changed, 451 insertions, 0 deletions

diff --git a/src/string_utils.cc b/src/string_utils.cc
new file mode 100644
index 00000000..06e0eb7c
--- /dev/null
+++ b/src/string_utils.cc
@@ -0,0 +1,451 @@
+#include "string_utils.hh"
+
+#include "exception.hh"
+#include "utf8_iterator.hh"
+#include "unit_tests.hh"
+
+namespace Kakoune
+{
+
+Vector<String> split(StringView str, char separator, char escape)
+{
+    Vector<String> res;
+    auto it = str.begin();
+    auto start = it;
+    while (it != str.end())
+    {
+        res.emplace_back();
+        String& element = res.back();
+        while (it != str.end())
+        {
+            auto c = *it;
+            if (c == escape and it + 1 != str.end() and *(it+1) == separator)
+            {
+                element += StringView{start, it+1};
+                element.back() = separator;
+                it += 2;
+                start = it;
+            }
+            else if (c == separator)
+            {
+                element += StringView{start, it};
+                ++it;
+                start = it;
+                break;
+            }
+            else
+                ++it;
+        }
+    }
+    if (start != str.end())
+        res.back() += StringView{start, str.end()};
+    return res;
+}
+
+Vector<StringView> split(StringView str, char separator)
+{
+    Vector<StringView> res;
+    if (str.empty())
+        return res;
+
+    auto beg = str.begin();
+    for (auto it = beg; it != str.end(); ++it)
+    {
+        if (*it == separator)
+        {
+            res.emplace_back(beg, it);
+            beg = it + 1;
+        }
+    }
+    res.emplace_back(beg, str.end());
+    return res;
+}
+
+StringView trim_whitespaces(StringView str)
+{
+    auto beg = str.begin(), end = str.end();
+    while (beg != end and is_blank(*beg))
+        ++beg;
+    while (beg != end and is_blank(*(end-1)))
+        --end;
+    return {beg, end};
+}
+
+
+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);
+
+    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<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(size_t val)
+{
+    InplaceString<23> res;
+    res.m_length = sprintf(res.m_data, "%zu", 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;
+}
+
+Vector<StringView> wrap_lines(StringView text, ColumnCount max_width)
+{
+    if (max_width <= 0)
+        throw runtime_error("Invalid max width");
+
+    using Utf8It = utf8::iterator<const char*>;
+    Utf8It it{text.begin(), text};
+    Utf8It end{text.end(), text};
+    Utf8It line_begin = it;
+    Utf8It last_word_end = it;
+
+    Vector<StringView> lines;
+    while (it != end)
+    {
+        const CharCategories cat = categorize(*it, {});
+        if (cat == CharCategories::EndOfLine)
+        {
+            lines.emplace_back(line_begin.base(), it.base());
+            line_begin = it = it+1;
+            continue;
+        }
+
+        Utf8It word_end = it+1;
+        while (word_end != end and categorize(*word_end, {}) == cat)
+            ++word_end;
+
+        while (word_end > line_begin and
+               utf8::column_distance(line_begin.base(), word_end.base()) >= max_width)
+        {
+            auto line_end = last_word_end <= line_begin ?
+                Utf8It{utf8::advance(line_begin.base(), text.end(), max_width), text}
+              : last_word_end;
+
+            lines.emplace_back(line_begin.base(), line_end.base());
+
+            while (line_end != end and is_horizontal_blank(*line_end))
+                ++line_end;
+
+            if (line_end != end and *line_end == '\n')
+                ++line_end;
+
+            it = line_begin = line_end;
+        }
+        if (cat == CharCategories::Word or cat == CharCategories::Punctuation)
+            last_word_end = word_end;
+
+        if (word_end > line_begin)
+            it = word_end;
+    }
+    if (line_begin != end)
+        lines.emplace_back(line_begin.base(), text.end());
+    return lines;
+}
+
+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;
+}
+
+UnitTest test_string{[]()
+{
+    kak_assert(String("youpi ") + "matin" == "youpi matin");
+
+    Vector<String> splited = split("youpi:matin::tchou\\:kanaky:hihi\\:", ':', '\\');
+    kak_assert(splited[0] == "youpi");
+    kak_assert(splited[1] == "matin");
+    kak_assert(splited[2] == "");
+    kak_assert(splited[3] == "tchou:kanaky");
+    kak_assert(splited[4] == "hihi:");
+
+    Vector<StringView> splitedview = split("youpi:matin::tchou\\:kanaky:hihi\\:", ':');
+    kak_assert(splitedview[0] == "youpi");
+    kak_assert(splitedview[1] == "matin");
+    kak_assert(splitedview[2] == "");
+    kak_assert(splitedview[3] == "tchou\\");
+    kak_assert(splitedview[4] == "kanaky");
+    kak_assert(splitedview[5] == "hihi\\");
+    kak_assert(splitedview[6] == "");
+
+    Vector<StringView> wrapped = wrap_lines("wrap this paragraph\n respecting whitespaces and much_too_long_words", 16);
+    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");
+
+    Vector<StringView> wrapped2 = wrap_lines("error: unknown type", 7);
+    kak_assert(wrapped2.size() == 3);
+    kak_assert(wrapped2[0] == "error:");
+    kak_assert(wrapped2[1] == "unknown");
+    kak_assert(wrapped2[2] == "type");
+
+    kak_assert(escape("youpi:matin:tchou:", ':', '\\') == "youpi\\:matin\\:tchou\\:");
+    kak_assert(unescape("youpi\\:matin\\:tchou\\:", ':', '\\') == "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(replace("tchou/tcha/tchi", "/", "!!") == "tchou!!tcha!!tchi");
+}};
+
+}