diff options
Diffstat (limited to 'Python/ast.c')
| -rw-r--r-- | Python/ast.c | 112 |
1 files changed, 83 insertions, 29 deletions
diff --git a/Python/ast.c b/Python/ast.c index 4687f81..21abd7e 100644 --- a/Python/ast.c +++ b/Python/ast.c @@ -4854,7 +4854,8 @@ fstring_compile_expr(const char *expr_start, const char *expr_end, assert(expr_end >= expr_start); assert(*(expr_start-1) == '{'); - assert(*expr_end == '}' || *expr_end == '!' || *expr_end == ':'); + assert(*expr_end == '}' || *expr_end == '!' || *expr_end == ':' || + *expr_end == '='); /* If the substring is all whitespace, it's an error. We need to catch this here, and not when we call PyParser_SimpleParseStringFlagsFilename, @@ -4997,9 +4998,9 @@ fstring_parse(const char **str, const char *end, int raw, int recurse_lvl, struct compiling *c, const node *n); /* Parse the f-string at *str, ending at end. We know *str starts an - expression (so it must be a '{'). Returns the FormattedValue node, - which includes the expression, conversion character, and - format_spec expression. + expression (so it must be a '{'). Returns the FormattedValue node, which + includes the expression, conversion character, format_spec expression, and + optionally the text of the expression (if = is used). Note that I don't do a perfect job here: I don't make sure that a closing brace doesn't match an opening paren, for example. It @@ -5016,7 +5017,12 @@ fstring_find_expr(const char **str, const char *end, int raw, int recurse_lvl, const char *expr_end; expr_ty simple_expression; expr_ty format_spec = NULL; /* Optional format specifier. */ - int conversion = -1; /* The conversion char. -1 if not specified. */ + int conversion = -1; /* The conversion char. Use default if not + specified, or !r if using = and no format + spec. */ + int equal_flag = 0; /* Are we using the = feature? */ + PyObject *expr_text = NULL; /* The text of the expression, used for =. */ + const char *expr_text_end; /* 0 if we're not in a string, else the quote char we're trying to match (single or double quote). */ @@ -5033,7 +5039,7 @@ fstring_find_expr(const char **str, const char *end, int raw, int recurse_lvl, /* Can only nest one level deep. */ if (recurse_lvl >= 2) { ast_error(c, n, "f-string: expressions nested too deeply"); - return -1; + goto error; } /* The first char must be a left brace, or we wouldn't have gotten @@ -5061,7 +5067,7 @@ fstring_find_expr(const char **str, const char *end, int raw, int recurse_lvl, ast_error(c, n, "f-string expression part " "cannot include a backslash"); - return -1; + goto error; } if (quote_char) { /* We're inside a string. See if we're at the end. */ @@ -5106,7 +5112,7 @@ fstring_find_expr(const char **str, const char *end, int raw, int recurse_lvl, } else if (ch == '[' || ch == '{' || ch == '(') { if (nested_depth >= MAXLEVEL) { ast_error(c, n, "f-string: too many nested parenthesis"); - return -1; + goto error; } parenstack[nested_depth] = ch; nested_depth++; @@ -5114,22 +5120,38 @@ fstring_find_expr(const char **str, const char *end, int raw, int recurse_lvl, /* Error: can't include a comment character, inside parens or not. */ ast_error(c, n, "f-string expression part cannot include '#'"); - return -1; + goto error; } else if (nested_depth == 0 && - (ch == '!' || ch == ':' || ch == '}')) { - /* First, test for the special case of "!=". Since '=' is - not an allowed conversion character, nothing is lost in - this test. */ - if (ch == '!' && *str+1 < end && *(*str+1) == '=') { - /* This isn't a conversion character, just continue. */ - continue; + (ch == '!' || ch == ':' || ch == '}' || + ch == '=' || ch == '>' || ch == '<')) { + /* See if there's a next character. */ + if (*str+1 < end) { + char next = *(*str+1); + + /* For "!=". since '=' is not an allowed conversion character, + nothing is lost in this test. */ + if ((ch == '!' && next == '=') || /* != */ + (ch == '=' && next == '=') || /* == */ + (ch == '<' && next == '=') || /* <= */ + (ch == '>' && next == '=') /* >= */ + ) { + *str += 1; + continue; + } + /* Don't get out of the loop for these, if they're single + chars (not part of 2-char tokens). If by themselves, they + don't end an expression (unlike say '!'). */ + if (ch == '>' || ch == '<') { + continue; + } } + /* Normal way out of this loop. */ break; } else if (ch == ']' || ch == '}' || ch == ')') { if (!nested_depth) { ast_error(c, n, "f-string: unmatched '%c'", ch); - return -1; + goto error; } nested_depth--; int opening = parenstack[nested_depth]; @@ -5141,7 +5163,7 @@ fstring_find_expr(const char **str, const char *end, int raw, int recurse_lvl, "f-string: closing parenthesis '%c' " "does not match opening parenthesis '%c'", ch, opening); - return -1; + goto error; } } else { /* Just consume this char and loop around. */ @@ -5154,12 +5176,12 @@ fstring_find_expr(const char **str, const char *end, int raw, int recurse_lvl, let's just do that.*/ if (quote_char) { ast_error(c, n, "f-string: unterminated string"); - return -1; + goto error; } if (nested_depth) { int opening = parenstack[nested_depth - 1]; ast_error(c, n, "f-string: unmatched '%c'", opening); - return -1; + goto error; } if (*str >= end) @@ -5170,7 +5192,22 @@ fstring_find_expr(const char **str, const char *end, int raw, int recurse_lvl, conversion or format_spec. */ simple_expression = fstring_compile_expr(expr_start, expr_end, c, n); if (!simple_expression) - return -1; + goto error; + + /* Check for =, which puts the text value of the expression in + expr_text. */ + if (**str == '=') { + *str += 1; + equal_flag = 1; + + /* Skip over ASCII whitespace. No need to test for end of string + here, since we know there's at least a trailing quote somewhere + ahead. */ + while (Py_ISSPACE(**str)) { + *str += 1; + } + expr_text_end = *str; + } /* Check for a conversion char, if present. */ if (**str == '!') { @@ -5182,13 +5219,19 @@ fstring_find_expr(const char **str, const char *end, int raw, int recurse_lvl, *str += 1; /* Validate the conversion. */ - if (!(conversion == 's' || conversion == 'r' - || conversion == 'a')) { + if (!(conversion == 's' || conversion == 'r' || conversion == 'a')) { ast_error(c, n, "f-string: invalid conversion character: " "expected 's', 'r', or 'a'"); - return -1; + goto error; } + + } + if (equal_flag) { + Py_ssize_t len = expr_text_end-expr_start; + expr_text = PyUnicode_FromStringAndSize(expr_start, len); + if (!expr_text) + goto error; } /* Check for the format spec, if present. */ @@ -5202,7 +5245,7 @@ fstring_find_expr(const char **str, const char *end, int raw, int recurse_lvl, /* Parse the format spec. */ format_spec = fstring_parse(str, end, raw, recurse_lvl+1, c, n); if (!format_spec) - return -1; + goto error; } if (*str >= end || **str != '}') @@ -5213,20 +5256,31 @@ fstring_find_expr(const char **str, const char *end, int raw, int recurse_lvl, assert(**str == '}'); *str += 1; + /* If we're in = mode, and have no format spec and no explict conversion, + set the conversion to 'r'. */ + if (equal_flag && format_spec == NULL && conversion == -1) { + conversion = 'r'; + } + /* And now create the FormattedValue node that represents this entire expression with the conversion and format spec. */ *expression = FormattedValue(simple_expression, conversion, - format_spec, LINENO(n), n->n_col_offset, - n->n_end_lineno, n->n_end_col_offset, - c->c_arena); + format_spec, expr_text, LINENO(n), + n->n_col_offset, n->n_end_lineno, + n->n_end_col_offset, c->c_arena); if (!*expression) - return -1; + goto error; return 0; unexpected_end_of_string: ast_error(c, n, "f-string: expecting '}'"); + /* Falls through to error. */ + +error: + Py_XDECREF(expr_text); return -1; + } /* Return -1 on error. |