🔨 simplifying scanner

This commit is contained in:
Niels Lohmann 2017-06-22 16:40:15 +02:00
parent 3dc5d95422
commit e99b783def
No known key found for this signature in database
GPG key ID: 7F3CEA63AE251B69
2 changed files with 34 additions and 60 deletions

View file

@ -11461,17 +11461,6 @@ class basic_json
return codepoint; return codepoint;
} }
/*!
@brief create diagnostic representation of a codepoint
@return string "U+XXXX" for codepoint XXXX
*/
static std::string codepoint_to_string(int codepoint)
{
std::stringstream ss;
ss << "U+" << std::setw(4) << std::uppercase << std::setfill('0') << std::hex << codepoint;
return ss.str();
}
/*! /*!
@brief scan a string literal @brief scan a string literal
@ -11497,9 +11486,7 @@ class basic_json
while (true) while (true)
{ {
// get next character // get next character
get(); switch (get())
switch (current)
{ {
// end of file while parsing string // end of file while parsing string
case std::char_traits<char>::eof(): case std::char_traits<char>::eof():
@ -12396,40 +12383,24 @@ scan_number_done:
return token_type::value_float; return token_type::value_float;
} }
token_type scan_true() /*!
@param[in] literal_text the literal text to expect
@param[in] length the length of the passed literal text
@param[in] return_type the token type to return on success
*/
token_type scan_literal(const char* literal_text, const size_t length,
token_type return_type)
{ {
assert(current == 't'); assert(current == literal_text[0]);
if (JSON_LIKELY((get() == 'r' and get() == 'u' and get() == 'e'))) for (size_t i = 1; i < length; ++i)
{ {
return token_type::literal_true; if (JSON_UNLIKELY(get() != literal_text[i]))
} {
error_message = "invalid literal";
error_message = "invalid literal; expected 'true'";
return token_type::parse_error; return token_type::parse_error;
} }
token_type scan_false()
{
assert(current == 'f');
if (JSON_LIKELY((get() == 'a' and get() == 'l' and get() == 's' and get() == 'e')))
{
return token_type::literal_false;
} }
return return_type;
error_message = "invalid literal; expected 'false'";
return token_type::parse_error;
}
token_type scan_null()
{
assert(current == 'n');
if (JSON_LIKELY((get() == 'u' and get() == 'l' and get() == 'l')))
{
return token_type::literal_null;
}
error_message = "invalid literal; expected 'null'";
return token_type::parse_error;
} }
///////////////////// /////////////////////
@ -12461,6 +12432,7 @@ scan_number_done:
{ {
yytext.resize(2 * yytext.capacity(), '\0'); yytext.resize(2 * yytext.capacity(), '\0');
} }
assert(yylen < yytext.size());
yytext[yylen++] = static_cast<char>(c); yytext[yylen++] = static_cast<char>(c);
} }
@ -12523,7 +12495,9 @@ scan_number_done:
else if ('\x00' <= c and c <= '\x1f') else if ('\x00' <= c and c <= '\x1f')
{ {
// escape control characters // escape control characters
result += "<" + codepoint_to_string(c) + ">"; std::stringstream ss;
ss << "<U+" << std::setw(4) << std::uppercase << std::setfill('0') << std::hex << static_cast<int>(c) << ">";
result += ss.str();
} }
else else
{ {
@ -12572,11 +12546,11 @@ scan_number_done:
// literals // literals
case 't': case 't':
return scan_true(); return scan_literal("true", 4, token_type::literal_true);
case 'f': case 'f':
return scan_false(); return scan_literal("false", 5, token_type::literal_false);
case 'n': case 'n':
return scan_null(); return scan_literal("null", 4, token_type::literal_null);
// string // string
case '\"': case '\"':

View file

@ -338,7 +338,7 @@ TEST_CASE("parser class")
CHECK_THROWS_WITH(json::parser(json::input_adapter::create(std::string("-0e-:"))).parse(), CHECK_THROWS_WITH(json::parser(json::input_adapter::create(std::string("-0e-:"))).parse(),
"[json.exception.parse_error.101] parse error at 5: syntax error - invalid number; expected digit after exponent sign; last read: '-0e-:'"); "[json.exception.parse_error.101] parse error at 5: syntax error - invalid number; expected digit after exponent sign; last read: '-0e-:'");
CHECK_THROWS_WITH(json::parser(json::input_adapter::create(std::string("-0f"))).parse(), CHECK_THROWS_WITH(json::parser(json::input_adapter::create(std::string("-0f"))).parse(),
"[json.exception.parse_error.101] parse error at 4: syntax error - invalid literal; expected 'false'; last read: '-0f'; expected end of input"); "[json.exception.parse_error.101] parse error at 4: syntax error - invalid literal; last read: '-0f'; expected end of input");
} }
} }
} }
@ -656,22 +656,22 @@ TEST_CASE("parser class")
CHECK_THROWS_AS(json::parser(json::input_adapter::create(std::string("nu"))).parse(), json::parse_error); CHECK_THROWS_AS(json::parser(json::input_adapter::create(std::string("nu"))).parse(), json::parse_error);
CHECK_THROWS_AS(json::parser(json::input_adapter::create(std::string("nul"))).parse(), json::parse_error); CHECK_THROWS_AS(json::parser(json::input_adapter::create(std::string("nul"))).parse(), json::parse_error);
CHECK_THROWS_WITH(json::parser(json::input_adapter::create(std::string("n"))).parse(), CHECK_THROWS_WITH(json::parser(json::input_adapter::create(std::string("n"))).parse(),
"[json.exception.parse_error.101] parse error at 2: syntax error - invalid literal; expected 'null'; last read: 'n'"); "[json.exception.parse_error.101] parse error at 2: syntax error - invalid literal; last read: 'n'");
CHECK_THROWS_WITH(json::parser(json::input_adapter::create(std::string("nu"))).parse(), CHECK_THROWS_WITH(json::parser(json::input_adapter::create(std::string("nu"))).parse(),
"[json.exception.parse_error.101] parse error at 3: syntax error - invalid literal; expected 'null'; last read: 'nu'"); "[json.exception.parse_error.101] parse error at 3: syntax error - invalid literal; last read: 'nu'");
CHECK_THROWS_WITH(json::parser(json::input_adapter::create(std::string("nul"))).parse(), CHECK_THROWS_WITH(json::parser(json::input_adapter::create(std::string("nul"))).parse(),
"[json.exception.parse_error.101] parse error at 4: syntax error - invalid literal; expected 'null'; last read: 'nul'"); "[json.exception.parse_error.101] parse error at 4: syntax error - invalid literal; last read: 'nul'");
// unexpected end of true // unexpected end of true
CHECK_THROWS_AS(json::parser(json::input_adapter::create(std::string("t"))).parse(), json::parse_error); CHECK_THROWS_AS(json::parser(json::input_adapter::create(std::string("t"))).parse(), json::parse_error);
CHECK_THROWS_AS(json::parser(json::input_adapter::create(std::string("tr"))).parse(), json::parse_error); CHECK_THROWS_AS(json::parser(json::input_adapter::create(std::string("tr"))).parse(), json::parse_error);
CHECK_THROWS_AS(json::parser(json::input_adapter::create(std::string("tru"))).parse(), json::parse_error); CHECK_THROWS_AS(json::parser(json::input_adapter::create(std::string("tru"))).parse(), json::parse_error);
CHECK_THROWS_WITH(json::parser(json::input_adapter::create(std::string("t"))).parse(), CHECK_THROWS_WITH(json::parser(json::input_adapter::create(std::string("t"))).parse(),
"[json.exception.parse_error.101] parse error at 2: syntax error - invalid literal; expected 'true'; last read: 't'"); "[json.exception.parse_error.101] parse error at 2: syntax error - invalid literal; last read: 't'");
CHECK_THROWS_WITH(json::parser(json::input_adapter::create(std::string("tr"))).parse(), CHECK_THROWS_WITH(json::parser(json::input_adapter::create(std::string("tr"))).parse(),
"[json.exception.parse_error.101] parse error at 3: syntax error - invalid literal; expected 'true'; last read: 'tr'"); "[json.exception.parse_error.101] parse error at 3: syntax error - invalid literal; last read: 'tr'");
CHECK_THROWS_WITH(json::parser(json::input_adapter::create(std::string("tru"))).parse(), CHECK_THROWS_WITH(json::parser(json::input_adapter::create(std::string("tru"))).parse(),
"[json.exception.parse_error.101] parse error at 4: syntax error - invalid literal; expected 'true'; last read: 'tru'"); "[json.exception.parse_error.101] parse error at 4: syntax error - invalid literal; last read: 'tru'");
// unexpected end of false // unexpected end of false
CHECK_THROWS_AS(json::parser(json::input_adapter::create(std::string("f"))).parse(), json::parse_error); CHECK_THROWS_AS(json::parser(json::input_adapter::create(std::string("f"))).parse(), json::parse_error);
@ -679,13 +679,13 @@ TEST_CASE("parser class")
CHECK_THROWS_AS(json::parser(json::input_adapter::create(std::string("fal"))).parse(), json::parse_error); CHECK_THROWS_AS(json::parser(json::input_adapter::create(std::string("fal"))).parse(), json::parse_error);
CHECK_THROWS_AS(json::parser(json::input_adapter::create(std::string("fals"))).parse(), json::parse_error); CHECK_THROWS_AS(json::parser(json::input_adapter::create(std::string("fals"))).parse(), json::parse_error);
CHECK_THROWS_WITH(json::parser(json::input_adapter::create(std::string("f"))).parse(), CHECK_THROWS_WITH(json::parser(json::input_adapter::create(std::string("f"))).parse(),
"[json.exception.parse_error.101] parse error at 2: syntax error - invalid literal; expected 'false'; last read: 'f'"); "[json.exception.parse_error.101] parse error at 2: syntax error - invalid literal; last read: 'f'");
CHECK_THROWS_WITH(json::parser(json::input_adapter::create(std::string("fa"))).parse(), CHECK_THROWS_WITH(json::parser(json::input_adapter::create(std::string("fa"))).parse(),
"[json.exception.parse_error.101] parse error at 3: syntax error - invalid literal; expected 'false'; last read: 'fa'"); "[json.exception.parse_error.101] parse error at 3: syntax error - invalid literal; last read: 'fa'");
CHECK_THROWS_WITH(json::parser(json::input_adapter::create(std::string("fal"))).parse(), CHECK_THROWS_WITH(json::parser(json::input_adapter::create(std::string("fal"))).parse(),
"[json.exception.parse_error.101] parse error at 4: syntax error - invalid literal; expected 'false'; last read: 'fal'"); "[json.exception.parse_error.101] parse error at 4: syntax error - invalid literal; last read: 'fal'");
CHECK_THROWS_WITH(json::parser(json::input_adapter::create(std::string("fals"))).parse(), CHECK_THROWS_WITH(json::parser(json::input_adapter::create(std::string("fals"))).parse(),
"[json.exception.parse_error.101] parse error at 5: syntax error - invalid literal; expected 'false'; last read: 'fals'"); "[json.exception.parse_error.101] parse error at 5: syntax error - invalid literal; last read: 'fals'");
// missing/unexpected end of array // missing/unexpected end of array
CHECK_THROWS_AS(json::parser(json::input_adapter::create(std::string("["))).parse(), json::parse_error); CHECK_THROWS_AS(json::parser(json::input_adapter::create(std::string("["))).parse(), json::parse_error);