fish-shell/src/parser_keywords.cpp
2022-06-16 19:45:55 +10:00

71 lines
2.7 KiB
C++

// Functions having to do with parser keywords, like testing if a function is a block command.
#include "config.h" // IWYU pragma: keep
#include "parser_keywords.h"
#include <string>
#include <unordered_set>
#include "common.h"
#include "fallback.h" // IWYU pragma: keep
using string_set_t = std::unordered_set<wcstring>;
static const wcstring skip_keywords[]{
L"else",
L"begin",
};
static const wcstring subcommand_keywords[]{L"command", L"builtin", L"while", L"exec", L"if",
L"and", L"or", L"not", L"time", L"begin"};
static const string_set_t block_keywords = {L"for", L"while", L"if",
L"function", L"switch", L"begin"};
// Don't forget to add any new reserved keywords to the documentation
static const wcstring reserved_keywords[] = {
L"end", L"case", L"else", L"return", L"continue", L"break", L"argparse", L"read",
L"string", L"set", L"status", L"test", L"[", L"_", L"eval"};
// The lists above are purposely implemented separately from the logic below, so that future
// maintainers may assume the contents of the list based off their names, and not off what the
// functions below require them to contain.
static size_t list_max_length(const string_set_t &list) {
size_t result = 0;
for (const auto &w : list) {
if (w.length() > result) {
result = w.length();
}
}
return result;
}
bool parser_keywords_is_subcommand(const wcstring &cmd) {
const static string_set_t search_list = ([] {
string_set_t results;
results.insert(std::begin(subcommand_keywords), std::end(subcommand_keywords));
results.insert(std::begin(skip_keywords), std::end(skip_keywords));
return results;
})();
const static auto max_len = list_max_length(search_list);
const static auto not_found = search_list.end();
// Everything above is executed only at startup, this is the actual optimized search routine:
return cmd.length() <= max_len && search_list.find(cmd) != not_found;
}
bool parser_keywords_is_reserved(const wcstring &word) {
const static string_set_t search_list = ([] {
string_set_t results;
results.insert(std::begin(subcommand_keywords), std::end(subcommand_keywords));
results.insert(std::begin(skip_keywords), std::end(skip_keywords));
results.insert(std::begin(block_keywords), std::end(block_keywords));
results.insert(std::begin(reserved_keywords), std::end(reserved_keywords));
return results;
})();
const static size_t max_len = list_max_length(search_list);
return word.length() <= max_len && search_list.count(word) > 0;
}