djsundog/circuitpython
1
0
Fork 0
Code Issues Pull Requests Packages Projects Releases Wiki Activity
20d3a6b196
circuitpython/py/lexer.c
Jared Hancock b3cd41dd4b py/lexer: Allow conversion specifiers in f-strings (e.g. !r). 
PEP-498 allows for conversion specifiers like !r and !s to convert the
expression declared in braces to be passed through repr() and str()
respectively.

This updates the logic that detects the end of the expression to also stop
when it sees "![rs]" that is either at the end of the f-string or before
the ":" indicating the start of the format specifier. The "![rs]" is now
retained in the format string, whereas previously it stayed on the end
of the expression leading to a syntax error.

Previously: `f"{x!y:z}"` --> `"{:z}".format(x!y)`
Now: `f"{x!y:z}"` --> `"{!y:z}".format(x)`

Note that "!a" is not supported by `str.format` as MicroPython has no
`ascii()`, but now this will raise the correct error.

Updated cpydiff and added tests.

Signed-off-by: Jim Mussared <jim.mussared@gmail.com>
2023-06-14 19:11:04 +10:00

935 lines
33 KiB
C
Raw Blame History

/*
* This file is part of the MicroPython project, http://micropython.org/
*
* The MIT License (MIT)
*
* Copyright (c) 2013, 2014 Damien P. George
*
* Permission is hereby granted, free of charge, to any person obtaining a copy
* of this software and associated documentation files (the "Software"), to deal
* in the Software without restriction, including without limitation the rights
* to use, copy, modify, merge, publish, distribute, sublicense, and/or sell
* copies of the Software, and to permit persons to whom the Software is
* furnished to do so, subject to the following conditions:
*
* The above copyright notice and this permission notice shall be included in
* all copies or substantial portions of the Software.
*
* THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
* IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
* FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE
* AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
* LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
* OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN
* THE SOFTWARE.
*/
#include <stdio.h>
#include <string.h>
#include <assert.h>
#include "py/reader.h"
#include "py/lexer.h"
#include "py/runtime.h"
#if MICROPY_ENABLE_COMPILER
#define TAB_SIZE (8)
// TODO seems that CPython allows NULL byte in the input stream
// don't know if that's intentional or not, but we don't allow it
#define MP_LEXER_EOF ((unichar)MP_READER_EOF)
#define CUR_CHAR(lex) ((lex)->chr0)
STATIC bool is_end(mp_lexer_t *lex) {
return lex->chr0 == MP_LEXER_EOF;
}
STATIC bool is_physical_newline(mp_lexer_t *lex) {
return lex->chr0 == '\n';
}
STATIC bool is_char(mp_lexer_t *lex, byte c) {
return lex->chr0 == c;
}
STATIC bool is_char_or(mp_lexer_t *lex, byte c1, byte c2) {
return lex->chr0 == c1 || lex->chr0 == c2;
}
STATIC bool is_char_or3(mp_lexer_t *lex, byte c1, byte c2, byte c3) {
return lex->chr0 == c1 || lex->chr0 == c2 || lex->chr0 == c3;
}
#if MICROPY_PY_FSTRINGS
STATIC bool is_char_or4(mp_lexer_t *lex, byte c1, byte c2, byte c3, byte c4) {
return lex->chr0 == c1 || lex->chr0 == c2 || lex->chr0 == c3 || lex->chr0 == c4;
}
#endif
STATIC bool is_char_following(mp_lexer_t *lex, byte c) {
return lex->chr1 == c;
}
STATIC bool is_char_following_or(mp_lexer_t *lex, byte c1, byte c2) {
return lex->chr1 == c1 || lex->chr1 == c2;
}
STATIC bool is_char_following_following_or(mp_lexer_t *lex, byte c1, byte c2) {
return lex->chr2 == c1 || lex->chr2 == c2;
}
STATIC bool is_char_and(mp_lexer_t *lex, byte c1, byte c2) {
return lex->chr0 == c1 && lex->chr1 == c2;
}
STATIC bool is_whitespace(mp_lexer_t *lex) {
return unichar_isspace(lex->chr0);
}
STATIC bool is_letter(mp_lexer_t *lex) {
return unichar_isalpha(lex->chr0);
}
STATIC bool is_digit(mp_lexer_t *lex) {
return unichar_isdigit(lex->chr0);
}
STATIC bool is_following_digit(mp_lexer_t *lex) {
return unichar_isdigit(lex->chr1);
}
STATIC bool is_following_base_char(mp_lexer_t *lex) {
const unichar chr1 = lex->chr1 | 0x20;
return chr1 == 'b' || chr1 == 'o' || chr1 == 'x';
}
STATIC bool is_following_odigit(mp_lexer_t *lex) {
return lex->chr1 >= '0' && lex->chr1 <= '7';
}
STATIC bool is_string_or_bytes(mp_lexer_t *lex) {
return is_char_or(lex, '\'', '\"')
#if MICROPY_PY_FSTRINGS
|| (is_char_or4(lex, 'r', 'u', 'b', 'f') && is_char_following_or(lex, '\'', '\"'))
|| (((is_char_and(lex, 'r', 'f') || is_char_and(lex, 'f', 'r'))
&& is_char_following_following_or(lex, '\'', '\"')))
#else
|| (is_char_or3(lex, 'r', 'u', 'b') && is_char_following_or(lex, '\'', '\"'))
#endif
|| ((is_char_and(lex, 'r', 'b') || is_char_and(lex, 'b', 'r'))
&& is_char_following_following_or(lex, '\'', '\"'));
}
// to easily parse utf-8 identifiers we allow any raw byte with high bit set
STATIC bool is_head_of_identifier(mp_lexer_t *lex) {
return is_letter(lex) || lex->chr0 == '_' || lex->chr0 >= 0x80;
}
STATIC bool is_tail_of_identifier(mp_lexer_t *lex) {
return is_head_of_identifier(lex) || is_digit(lex);
}
STATIC void next_char(mp_lexer_t *lex) {
if (lex->chr0 == '\n') {
// a new line
++lex->line;
lex->column = 1;
} else if (lex->chr0 == '\t') {
// a tab
lex->column = (((lex->column - 1 + TAB_SIZE) / TAB_SIZE) * TAB_SIZE) + 1;
} else {
// a character worth one column
++lex->column;
}
// shift the input queue forward
lex->chr0 = lex->chr1;
lex->chr1 = lex->chr2;
// and add the next byte from either the fstring args or the reader
#if MICROPY_PY_FSTRINGS
if (lex->fstring_args_idx) {
// if there are saved chars, then we're currently injecting fstring args
if (lex->fstring_args_idx < lex->fstring_args.len) {
lex->chr2 = lex->fstring_args.buf[lex->fstring_args_idx++];
} else {
// no more fstring arg bytes
lex->chr2 = '\0';
}
if (lex->chr0 == '\0') {
// consumed all fstring data, restore saved input queue
lex->chr0 = lex->chr0_saved;
lex->chr1 = lex->chr1_saved;
lex->chr2 = lex->chr2_saved;
// stop consuming fstring arg data
vstr_reset(&lex->fstring_args);
lex->fstring_args_idx = 0;
}
} else
#endif
{
lex->chr2 = lex->reader.readbyte(lex->reader.data);
}
if (lex->chr1 == '\r') {
// CR is a new line, converted to LF
lex->chr1 = '\n';
if (lex->chr2 == '\n') {
// CR LF is a single new line, throw out the extra LF
lex->chr2 = lex->reader.readbyte(lex->reader.data);
}
}
// check if we need to insert a newline at end of file
if (lex->chr2 == MP_LEXER_EOF && lex->chr1 != MP_LEXER_EOF && lex->chr1 != '\n') {
lex->chr2 = '\n';
}
}
STATIC void indent_push(mp_lexer_t *lex, size_t indent) {
if (lex->num_indent_level >= lex->alloc_indent_level) {
lex->indent_level = m_renew(uint16_t, lex->indent_level, lex->alloc_indent_level, lex->alloc_indent_level + MICROPY_ALLOC_LEXEL_INDENT_INC);
lex->alloc_indent_level += MICROPY_ALLOC_LEXEL_INDENT_INC;
}
lex->indent_level[lex->num_indent_level++] = indent;
}
STATIC size_t indent_top(mp_lexer_t *lex) {
return lex->indent_level[lex->num_indent_level - 1];
}
STATIC void indent_pop(mp_lexer_t *lex) {
lex->num_indent_level -= 1;
}
// some tricky operator encoding:
// <op> = begin with <op>, if this opchar matches then begin here
// e<op> = end with <op>, if this opchar matches then end
// c<op> = continue with <op>, if this opchar matches then continue matching
// this means if the start of two ops are the same then they are equal til the last char
STATIC const char *const tok_enc =
"()[]{},;~" // singles
":e=" // : :=
"<e=c<e=" // < <= << <<=
">e=c>e=" // > >= >> >>=
"*e=c*e=" // * *= ** **=
"+e=" // + +=
"-e=e>" // - -= ->
"&e=" // & &=
"|e=" // | |=
"/e=c/e=" // / /= // //=
"%e=" // % %=
"^e=" // ^ ^=
"@e=" // @ @=
"=e=" // = ==
"!."; // start of special cases: != . ...
// TODO static assert that number of tokens is less than 256 so we can safely make this table with byte sized entries
STATIC const uint8_t tok_enc_kind[] = {
MP_TOKEN_DEL_PAREN_OPEN, MP_TOKEN_DEL_PAREN_CLOSE,
MP_TOKEN_DEL_BRACKET_OPEN, MP_TOKEN_DEL_BRACKET_CLOSE,
MP_TOKEN_DEL_BRACE_OPEN, MP_TOKEN_DEL_BRACE_CLOSE,
MP_TOKEN_DEL_COMMA, MP_TOKEN_DEL_SEMICOLON, MP_TOKEN_OP_TILDE,
MP_TOKEN_DEL_COLON, MP_TOKEN_OP_ASSIGN,
MP_TOKEN_OP_LESS, MP_TOKEN_OP_LESS_EQUAL, MP_TOKEN_OP_DBL_LESS, MP_TOKEN_DEL_DBL_LESS_EQUAL,
MP_TOKEN_OP_MORE, MP_TOKEN_OP_MORE_EQUAL, MP_TOKEN_OP_DBL_MORE, MP_TOKEN_DEL_DBL_MORE_EQUAL,
MP_TOKEN_OP_STAR, MP_TOKEN_DEL_STAR_EQUAL, MP_TOKEN_OP_DBL_STAR, MP_TOKEN_DEL_DBL_STAR_EQUAL,
MP_TOKEN_OP_PLUS, MP_TOKEN_DEL_PLUS_EQUAL,
MP_TOKEN_OP_MINUS, MP_TOKEN_DEL_MINUS_EQUAL, MP_TOKEN_DEL_MINUS_MORE,
MP_TOKEN_OP_AMPERSAND, MP_TOKEN_DEL_AMPERSAND_EQUAL,
MP_TOKEN_OP_PIPE, MP_TOKEN_DEL_PIPE_EQUAL,
MP_TOKEN_OP_SLASH, MP_TOKEN_DEL_SLASH_EQUAL, MP_TOKEN_OP_DBL_SLASH, MP_TOKEN_DEL_DBL_SLASH_EQUAL,
MP_TOKEN_OP_PERCENT, MP_TOKEN_DEL_PERCENT_EQUAL,
MP_TOKEN_OP_CARET, MP_TOKEN_DEL_CARET_EQUAL,
MP_TOKEN_OP_AT, MP_TOKEN_DEL_AT_EQUAL,
MP_TOKEN_DEL_EQUAL, MP_TOKEN_OP_DBL_EQUAL,
};
// must have the same order as enum in lexer.h
// must be sorted according to strcmp
STATIC const char *const tok_kw[] = {
"False",
"None",
"True",
"__debug__",
"and",
"as",
"assert",
#if MICROPY_PY_ASYNC_AWAIT
"async",
"await",
#endif
"break",
"class",
"continue",
"def",
"del",
"elif",
"else",
"except",
"finally",
"for",
"from",
"global",
"if",
"import",
"in",
"is",
"lambda",
"nonlocal",
"not",
"or",
"pass",
"raise",
"return",
"try",
"while",
"with",
"yield",
};
// This is called with CUR_CHAR() before first hex digit, and should return with
// it pointing to last hex digit
// num_digits must be greater than zero
STATIC bool get_hex(mp_lexer_t *lex, size_t num_digits, mp_uint_t *result) {
mp_uint_t num = 0;
while (num_digits-- != 0) {
next_char(lex);
unichar c = CUR_CHAR(lex);
if (!unichar_isxdigit(c)) {
return false;
}
num = (num << 4) + unichar_xdigit_value(c);
}
*result = num;
return true;
}
STATIC void parse_string_literal(mp_lexer_t *lex, bool is_raw, bool is_fstring) {
// get first quoting character
char quote_char = '\'';
if (is_char(lex, '\"')) {
quote_char = '\"';
}
next_char(lex);
// work out if it's a single or triple quoted literal
size_t num_quotes;
if (is_char_and(lex, quote_char, quote_char)) {
// triple quotes
next_char(lex);
next_char(lex);
num_quotes = 3;
} else {
// single quotes
num_quotes = 1;
}
size_t n_closing = 0;
#if MICROPY_PY_FSTRINGS
if (is_fstring) {
// assume there's going to be interpolation, so prep the injection data
// fstring_args_idx==0 && len(fstring_args)>0 means we're extracting the args.
// only when fstring_args_idx>0 will we consume the arg data
// note: lex->fstring_args will be empty already (it's reset when finished)
vstr_add_str(&lex->fstring_args, ".format(");
}
#endif
while (!is_end(lex) && (num_quotes > 1 || !is_char(lex, '\n')) && n_closing < num_quotes) {
if (is_char(lex, quote_char)) {
n_closing += 1;
vstr_add_char(&lex->vstr, CUR_CHAR(lex));
} else {
n_closing = 0;
#if MICROPY_PY_FSTRINGS
while (is_fstring && is_char(lex, '{')) {
next_char(lex);
if (is_char(lex, '{')) {
// "{{" is passed through unchanged to be handled by str.format
vstr_add_byte(&lex->vstr, '{');
next_char(lex);
} else {
// wrap each argument in (), e.g.
// f"{a,b,}, {c}" --> "{}".format((a,b), (c),)
vstr_add_byte(&lex->fstring_args, '(');
// remember the start of this argument (if we need it for f'{a=}').
size_t i = lex->fstring_args.len;
// Extract characters inside the { until the bracket level
// is zero and we reach the conversion specifier '!',
// format specifier ':', or closing '}'. The conversion
// and format specifiers are left unchanged in the format
// string to be handled by str.format.
// (MicroPython limitation) note: this is completely
// unaware of Python syntax and will not handle any
// expression containing '}' or ':'. e.g. f'{"}"}' or f'
// {foo({})}'. However, detection of the '!' will
// specifically ensure that it's followed by [rs] and
// then either the format specifier or the closing
// brace. This allows the use of e.g. != in expressions.
unsigned int nested_bracket_level = 0;
while (!is_end(lex) && (nested_bracket_level != 0
|| !(is_char_or(lex, ':', '}')
|| (is_char(lex, '!')
&& is_char_following_or(lex, 'r', 's')
&& is_char_following_following_or(lex, ':', '}'))))
) {
unichar c = CUR_CHAR(lex);
if (c == '[' || c == '{') {
nested_bracket_level += 1;
} else if (c == ']' || c == '}') {
nested_bracket_level -= 1;
}
// like the default case at the end of this function, stay 8-bit clean
vstr_add_byte(&lex->fstring_args, c);
next_char(lex);
}
if (lex->fstring_args.buf[lex->fstring_args.len - 1] == '=') {
// if the last character of the arg was '=', then inject "arg=" before the '{'.
// f'{a=}' --> 'a={}'.format(a)
vstr_add_strn(&lex->vstr, lex->fstring_args.buf + i, lex->fstring_args.len - i);
// remove the trailing '='
lex->fstring_args.len--;
}
// close the paren-wrapped arg to .format().
vstr_add_byte(&lex->fstring_args, ')');
// comma-separate args to .format().
vstr_add_byte(&lex->fstring_args, ',');
}
vstr_add_byte(&lex->vstr, '{');
}
#endif
if (is_char(lex, '\\')) {
next_char(lex);
unichar c = CUR_CHAR(lex);
if (is_raw) {
// raw strings allow escaping of quotes, but the backslash is also emitted
vstr_add_char(&lex->vstr, '\\');
} else {
switch (c) {
// note: "c" can never be MP_LEXER_EOF because next_char
// always inserts a newline at the end of the input stream
case '\n':
c = MP_LEXER_EOF;
break; // backslash escape the newline, just ignore it
case '\\':
break;
case '\'':
break;
case '"':
break;
case 'a':
c = 0x07;
break;
case 'b':
c = 0x08;
break;
case 't':
c = 0x09;
break;
case 'n':
c = 0x0a;
break;
case 'v':
c = 0x0b;
break;
case 'f':
c = 0x0c;
break;
case 'r':
c = 0x0d;
break;
case 'u':
case 'U':
if (lex->tok_kind == MP_TOKEN_BYTES) {
// b'\u1234' == b'\\u1234'
vstr_add_char(&lex->vstr, '\\');
break;
}
// Otherwise fall through.
MP_FALLTHROUGH
case 'x': {
mp_uint_t num = 0;
if (!get_hex(lex, (c == 'x' ? 2 : c == 'u' ? 4 : 8), &num)) {
// not enough hex chars for escape sequence
lex->tok_kind = MP_TOKEN_INVALID;
}
c = num;
break;
}
case 'N':
// Supporting '\N{LATIN SMALL LETTER A}' == 'a' would require keeping the
// entire Unicode name table in the core. As of Unicode 6.3.0, that's nearly
// 3MB of text; even gzip-compressed and with minimal structure, it'll take
// roughly half a meg of storage. This form of Unicode escape may be added
// later on, but it's definitely not a priority right now. -- CJA 20140607
mp_raise_NotImplementedError(MP_ERROR_TEXT("unicode name escapes"));
break;
default:
if (c >= '0' && c <= '7') {
// Octal sequence, 1-3 chars
size_t digits = 3;
mp_uint_t num = c - '0';
while (is_following_odigit(lex) && --digits != 0) {
next_char(lex);
num = num * 8 + (CUR_CHAR(lex) - '0');
}
c = num;
} else {
// unrecognised escape character; CPython lets this through verbatim as '\' and then the character
vstr_add_char(&lex->vstr, '\\');
}
break;
}
}
if (c != MP_LEXER_EOF) {
#if MICROPY_PY_BUILTINS_STR_UNICODE
if (c < 0x110000 && lex->tok_kind == MP_TOKEN_STRING) {
// Valid unicode character in a str object.
vstr_add_char(&lex->vstr, c);
} else if (c < 0x100 && lex->tok_kind == MP_TOKEN_BYTES) {
// Valid byte in a bytes object.
vstr_add_byte(&lex->vstr, c);
}
#else
if (c < 0x100) {
// Without unicode everything is just added as an 8-bit byte.
vstr_add_byte(&lex->vstr, c);
}
#endif
else {
// Character out of range; this raises a generic SyntaxError.
lex->tok_kind = MP_TOKEN_INVALID;
}
}
} else {
// Add the "character" as a byte so that we remain 8-bit clean.
// This way, strings are parsed correctly whether or not they contain utf-8 chars.
vstr_add_byte(&lex->vstr, CUR_CHAR(lex));
}
}
next_char(lex);
}
// check we got the required end quotes
if (n_closing < num_quotes) {
lex->tok_kind = MP_TOKEN_LONELY_STRING_OPEN;
}
// cut off the end quotes from the token text
vstr_cut_tail_bytes(&lex->vstr, n_closing);
}
STATIC bool skip_whitespace(mp_lexer_t *lex, bool stop_at_newline) {
bool had_physical_newline = false;
while (!is_end(lex)) {
if (is_physical_newline(lex)) {
if (stop_at_newline && lex->nested_bracket_level == 0) {
break;
}
had_physical_newline = true;
next_char(lex);
} else if (is_whitespace(lex)) {
next_char(lex);
} else if (is_char(lex, '#')) {
next_char(lex);
while (!is_end(lex) && !is_physical_newline(lex)) {
next_char(lex);
}
// had_physical_newline will be set on next loop
} else if (is_char_and(lex, '\\', '\n')) {
// line-continuation, so don't set had_physical_newline
next_char(lex);
next_char(lex);
} else {
break;
}
}
return had_physical_newline;
}
void mp_lexer_to_next(mp_lexer_t *lex) {
#if MICROPY_PY_FSTRINGS
if (lex->fstring_args.len && lex->fstring_args_idx == 0) {
// moving onto the next token means the literal string is complete.
// switch into injecting the format args.
vstr_add_byte(&lex->fstring_args, ')');
lex->chr0_saved = lex->chr0;
lex->chr1_saved = lex->chr1;
lex->chr2_saved = lex->chr2;
lex->chr0 = lex->fstring_args.buf[0];
lex->chr1 = lex->fstring_args.buf[1];
lex->chr2 = lex->fstring_args.buf[2];
// we've already extracted 3 chars, but setting this non-zero also
// means we'll start consuming the fstring data
lex->fstring_args_idx = 3;
}
#endif
// start new token text
vstr_reset(&lex->vstr);
// skip white space and comments
bool had_physical_newline = skip_whitespace(lex, false);
// set token source information
lex->tok_line = lex->line;
lex->tok_column = lex->column;
if (lex->emit_dent < 0) {
lex->tok_kind = MP_TOKEN_DEDENT;
lex->emit_dent += 1;
} else if (lex->emit_dent > 0) {
lex->tok_kind = MP_TOKEN_INDENT;
lex->emit_dent -= 1;
} else if (had_physical_newline && lex->nested_bracket_level == 0) {
lex->tok_kind = MP_TOKEN_NEWLINE;
size_t num_spaces = lex->column - 1;
if (num_spaces == indent_top(lex)) {
} else if (num_spaces > indent_top(lex)) {
indent_push(lex, num_spaces);
lex->emit_dent += 1;
} else {
while (num_spaces < indent_top(lex)) {
indent_pop(lex);
lex->emit_dent -= 1;
}
if (num_spaces != indent_top(lex)) {
lex->tok_kind = MP_TOKEN_DEDENT_MISMATCH;
}
}
} else if (is_end(lex)) {
lex->tok_kind = MP_TOKEN_END;
} else if (is_string_or_bytes(lex)) {
// a string or bytes literal
// Python requires adjacent string/bytes literals to be automatically
// concatenated. We do it here in the tokeniser to make efficient use of RAM,
// because then the lexer's vstr can be used to accumulate the string literal,
// in contrast to creating a parse tree of strings and then joining them later
// in the compiler. It's also more compact in code size to do it here.
// MP_TOKEN_END is used to indicate that this is the first string token
lex->tok_kind = MP_TOKEN_END;
// Loop to accumulate string/bytes literals
do {
// parse type codes
bool is_raw = false;
bool is_fstring = false;
mp_token_kind_t kind = MP_TOKEN_STRING;
int n_char = 0;
if (is_char(lex, 'u')) {
n_char = 1;
} else if (is_char(lex, 'b')) {
kind = MP_TOKEN_BYTES;
n_char = 1;
if (is_char_following(lex, 'r')) {
is_raw = true;
n_char = 2;
}
} else if (is_char(lex, 'r')) {
is_raw = true;
n_char = 1;
if (is_char_following(lex, 'b')) {
kind = MP_TOKEN_BYTES;
n_char = 2;
}
#if MICROPY_PY_FSTRINGS
if (is_char_following(lex, 'f')) {
// raw-f-strings unsupported, immediately return (invalid) token.
lex->tok_kind = MP_TOKEN_FSTRING_RAW;
break;
}
#endif
}
#if MICROPY_PY_FSTRINGS
else if (is_char(lex, 'f')) {
if (is_char_following(lex, 'r')) {
// raw-f-strings unsupported, immediately return (invalid) token.
lex->tok_kind = MP_TOKEN_FSTRING_RAW;
break;
}
n_char = 1;
is_fstring = true;
}
#endif
// Set or check token kind
if (lex->tok_kind == MP_TOKEN_END) {
lex->tok_kind = kind;
} else if (lex->tok_kind != kind) {
// Can't concatenate string with bytes
break;
}
// Skip any type code characters
if (n_char != 0) {
next_char(lex);
if (n_char == 2) {
next_char(lex);
}
}
// Parse the literal
parse_string_literal(lex, is_raw, is_fstring);
// Skip whitespace so we can check if there's another string following
skip_whitespace(lex, true);
} while (is_string_or_bytes(lex));
} else if (is_head_of_identifier(lex)) {
lex->tok_kind = MP_TOKEN_NAME;
// get first char (add as byte to remain 8-bit clean and support utf-8)
vstr_add_byte(&lex->vstr, CUR_CHAR(lex));
next_char(lex);
// get tail chars
while (!is_end(lex) && is_tail_of_identifier(lex)) {
vstr_add_byte(&lex->vstr, CUR_CHAR(lex));
next_char(lex);
}
// Check if the name is a keyword.
// We also check for __debug__ here and convert it to its value. This is
// so the parser gives a syntax error on, eg, x.__debug__. Otherwise, we
// need to check for this special token in many places in the compiler.
const char *s = vstr_null_terminated_str(&lex->vstr);
for (size_t i = 0; i < MP_ARRAY_SIZE(tok_kw); i++) {
int cmp = strcmp(s, tok_kw[i]);
if (cmp == 0) {
lex->tok_kind = MP_TOKEN_KW_FALSE + i;
if (lex->tok_kind == MP_TOKEN_KW___DEBUG__) {
lex->tok_kind = (MP_STATE_VM(mp_optimise_value) == 0 ? MP_TOKEN_KW_TRUE : MP_TOKEN_KW_FALSE);
}
break;
} else if (cmp < 0) {
// Table is sorted and comparison was less-than, so stop searching
break;
}
}
} else if (is_digit(lex) || (is_char(lex, '.') && is_following_digit(lex))) {
bool forced_integer = false;
if (is_char(lex, '.')) {
lex->tok_kind = MP_TOKEN_FLOAT_OR_IMAG;
} else {
lex->tok_kind = MP_TOKEN_INTEGER;
if (is_char(lex, '0') && is_following_base_char(lex)) {
forced_integer = true;
}
}
// get first char
vstr_add_char(&lex->vstr, CUR_CHAR(lex));
next_char(lex);
// get tail chars
while (!is_end(lex)) {
if (!forced_integer && is_char_or(lex, 'e', 'E')) {
lex->tok_kind = MP_TOKEN_FLOAT_OR_IMAG;
vstr_add_char(&lex->vstr, 'e');
next_char(lex);
if (is_char(lex, '+') || is_char(lex, '-')) {
vstr_add_char(&lex->vstr, CUR_CHAR(lex));
next_char(lex);
}
} else if (is_letter(lex) || is_digit(lex) || is_char(lex, '.')) {
if (is_char_or3(lex, '.', 'j', 'J')) {
lex->tok_kind = MP_TOKEN_FLOAT_OR_IMAG;
}
vstr_add_char(&lex->vstr, CUR_CHAR(lex));
next_char(lex);
} else if (is_char(lex, '_')) {
next_char(lex);
} else {
break;
}
}
} else {
// search for encoded delimiter or operator
const char *t = tok_enc;
size_t tok_enc_index = 0;
for (; *t != 0 && !is_char(lex, *t); t += 1) {
if (*t == 'e' || *t == 'c') {
t += 1;
}
tok_enc_index += 1;
}
next_char(lex);
if (*t == 0) {
// didn't match any delimiter or operator characters
lex->tok_kind = MP_TOKEN_INVALID;
} else if (*t == '!') {
// "!=" is a special case because "!" is not a valid operator
if (is_char(lex, '=')) {
next_char(lex);
lex->tok_kind = MP_TOKEN_OP_NOT_EQUAL;
} else {
lex->tok_kind = MP_TOKEN_INVALID;
}
} else if (*t == '.') {
// "." and "..." are special cases because ".." is not a valid operator
if (is_char_and(lex, '.', '.')) {
next_char(lex);
next_char(lex);
lex->tok_kind = MP_TOKEN_ELLIPSIS;
} else {
lex->tok_kind = MP_TOKEN_DEL_PERIOD;
}
} else {
// matched a delimiter or operator character
// get the maximum characters for a valid token
t += 1;
size_t t_index = tok_enc_index;
while (*t == 'c' || *t == 'e') {
t_index += 1;
if (is_char(lex, t[1])) {
next_char(lex);
tok_enc_index = t_index;
if (*t == 'e') {
break;
}
} else if (*t == 'c') {
break;
}
t += 2;
}
// set token kind
lex->tok_kind = tok_enc_kind[tok_enc_index];
// compute bracket level for implicit line joining
if (lex->tok_kind == MP_TOKEN_DEL_PAREN_OPEN || lex->tok_kind == MP_TOKEN_DEL_BRACKET_OPEN || lex->tok_kind == MP_TOKEN_DEL_BRACE_OPEN) {
lex->nested_bracket_level += 1;
} else if (lex->tok_kind == MP_TOKEN_DEL_PAREN_CLOSE || lex->tok_kind == MP_TOKEN_DEL_BRACKET_CLOSE || lex->tok_kind == MP_TOKEN_DEL_BRACE_CLOSE) {
lex->nested_bracket_level -= 1;
}
}
}
}
mp_lexer_t *mp_lexer_new(qstr src_name, mp_reader_t reader) {
mp_lexer_t *lex = m_new_obj(mp_lexer_t);
lex->source_name = src_name;
lex->reader = reader;
lex->line = 1;
lex->column = (size_t)-2; // account for 3 dummy bytes
lex->emit_dent = 0;
lex->nested_bracket_level = 0;
lex->alloc_indent_level = MICROPY_ALLOC_LEXER_INDENT_INIT;
lex->num_indent_level = 1;
lex->indent_level = m_new(uint16_t, lex->alloc_indent_level);
vstr_init(&lex->vstr, 32);
#if MICROPY_PY_FSTRINGS
vstr_init(&lex->fstring_args, 0);
#endif
// store sentinel for first indentation level
lex->indent_level[0] = 0;
// load lexer with start of file, advancing lex->column to 1
// start with dummy bytes and use next_char() for proper EOL/EOF handling
lex->chr0 = lex->chr1 = lex->chr2 = 0;
next_char(lex);
next_char(lex);
next_char(lex);
// preload first token
mp_lexer_to_next(lex);
// Check that the first token is in the first column. If it's not then we
// convert the token kind to INDENT so that the parser gives a syntax error.
if (lex->tok_column != 1) {
lex->tok_kind = MP_TOKEN_INDENT;
}
return lex;
}
mp_lexer_t *mp_lexer_new_from_str_len(qstr src_name, const char *str, size_t len, size_t free_len) {
mp_reader_t reader;
mp_reader_new_mem(&reader, (const byte *)str, len, free_len);
return mp_lexer_new(src_name, reader);
}
#if MICROPY_READER_POSIX || MICROPY_READER_VFS
mp_lexer_t *mp_lexer_new_from_file(const char *filename) {
mp_reader_t reader;
mp_reader_new_file(&reader, filename);
return mp_lexer_new(qstr_from_str(filename), reader);
}
#if MICROPY_HELPER_LEXER_UNIX
mp_lexer_t *mp_lexer_new_from_fd(qstr filename, int fd, bool close_fd) {
mp_reader_t reader;
mp_reader_new_file_from_fd(&reader, fd, close_fd);
return mp_lexer_new(filename, reader);
}
#endif
#endif
void mp_lexer_free(mp_lexer_t *lex) {
if (lex) {
lex->reader.close(lex->reader.data);
vstr_clear(&lex->vstr);
#if MICROPY_PY_FSTRINGS
vstr_clear(&lex->fstring_args);
#endif
m_del(uint16_t, lex->indent_level, lex->alloc_indent_level);
m_del_obj(mp_lexer_t, lex);
}
}
#if 0
// This function is used to print the current token and should only be
// needed to debug the lexer, so it's not available via a config option.
void mp_lexer_show_token(const mp_lexer_t *lex) {
printf("(" UINT_FMT ":" UINT_FMT ") kind:%u str:%p len:%zu", lex->tok_line, lex->tok_column, lex->tok_kind, lex->vstr.buf, lex->vstr.len);
if (lex->vstr.len > 0) {
const byte *i = (const byte *)lex->vstr.buf;
const byte *j = (const byte *)i + lex->vstr.len;
printf(" ");
while (i < j) {
unichar c = utf8_get_char(i);
i = utf8_next_char(i);
if (unichar_isprint(c)) {
printf("%c", (int)c);
} else {
printf("?");
}
}
}
printf("\n");
}
#endif
#endif // MICROPY_ENABLE_COMPILER
Reference in New Issue View Git Blame Copy Permalink