From 9f1b9932b87a6da14f2c010dfcf2ed08cb50b768 Mon Sep 17 00:00:00 2001 From: Jeremy Hylton Date: Wed, 28 Feb 2001 07:07:43 +0000 Subject: [PATCH] Print the offending line of code in the traceback for SyntaxErrors raised by the compiler. XXX For now, text entered into the interactive intepreter is not printed in the traceback. Inspired by a patch from Roman Sulzhyk compile.c: Add helper fetch_program_text() that opens a file and reads until it finds the specified line number. The code is a near duplicate of similar code in traceback.c. Modify com_error() to pass two arguments to SyntaxError constructor, where the second argument contains the offending text when possible. Modify set_error_location(), now used only by the symtable pass, to set the text attribute on existing exceptions. pythonrun.c: Change parse_syntax_error() to continue of the offset attribute of a SyntaxError is None. In this case, it sets offset to -1. Move code from PyErr_PrintEx() into helper function print_error_text(). In the helper, only print the caret for a SyntaxError if offset > 0. --- Python/compile.c | 127 ++++++++++++++++++++++++++++++++++----------- Python/pythonrun.c | 84 +++++++++++++++++------------- 2 files changed, 144 insertions(+), 67 deletions(-) diff --git a/Python/compile.c b/Python/compile.c index d9294d4ad90b6c..c540d6b4e71a69 100644 --- a/Python/compile.c +++ b/Python/compile.c @@ -381,41 +381,54 @@ int is_free(int v) return 0; } -/* Error message including line number */ +/* com_fetch_program_text will attempt to load the line of text that + the exception refers to. If it fails, it will return NULL but will + not set an exception. -static void -set_error_location(char *filename, int lineno) + XXX The functionality of this function is quite similar to the + functionality in tb_displayline() in traceback.c. +*/ + +static PyObject * +fetch_program_text(char *filename, int lineno) { - PyObject *exc, *v, *tb, *tmp; + FILE *fp; + int i; + char linebuf[1000]; - /* add attributes for the line number and filename for the error */ - PyErr_Fetch(&exc, &v, &tb); - PyErr_NormalizeException(&exc, &v, &tb); - tmp = PyInt_FromLong(lineno); - if (tmp == NULL) - PyErr_Clear(); - else { - if (PyObject_SetAttrString(v, "lineno", tmp)) - PyErr_Clear(); - Py_DECREF(tmp); - } - if (filename != NULL) { - tmp = PyString_FromString(filename); - if (tmp == NULL) - PyErr_Clear(); - else { - if (PyObject_SetAttrString(v, "filename", tmp)) - PyErr_Clear(); - Py_DECREF(tmp); - } + if (filename == NULL || lineno <= 0) + return NULL; + fp = fopen(filename, "r"); + if (fp == NULL) + return NULL; + for (i = 0; i < lineno; i++) { + char *pLastChar = &linebuf[sizeof(linebuf) - 2]; + do { + *pLastChar = '\0'; + if (fgets(linebuf, sizeof linebuf, fp) == NULL) + break; + /* fgets read *something*; if it didn't get as + far as pLastChar, it must have found a newline + or hit the end of the file; if pLastChar is \n, + it obviously found a newline; else we haven't + yet seen a newline, so must continue */ + } while (*pLastChar != '\0' && *pLastChar != '\n'); + } + fclose(fp); + if (i == lineno) { + char *p = linebuf; + while (*p == ' ' || *p == '\t' || *p == '\014') + p++; + return PyString_FromString(p); } - PyErr_Restore(exc, v, tb); + return NULL; } static void com_error(struct compiling *c, PyObject *exc, char *msg) { - PyObject *v; + PyObject *t = NULL, *v = NULL, *w = NULL, *line = NULL; + if (c == NULL) { /* Error occurred via symtable call to is_constant_false */ @@ -423,18 +436,33 @@ com_error(struct compiling *c, PyObject *exc, char *msg) return; } c->c_errors++; - if (c->c_lineno <= 1) { - /* Unknown line number or single interactive command */ + if (c->c_lineno < 1 || c->c_interactive) { + /* Unknown line number or interactive input */ PyErr_SetString(exc, msg); return; } v = PyString_FromString(msg); if (v == NULL) return; /* MemoryError, too bad */ - PyErr_SetObject(exc, v); - Py_DECREF(v); - set_error_location(c->c_filename, c->c_lineno); + line = fetch_program_text(c->c_filename, c->c_lineno); + if (line == NULL) { + Py_INCREF(Py_None); + line = Py_None; + } + t = Py_BuildValue("(ziOO)", c->c_filename, c->c_lineno, + Py_None, line); + if (t == NULL) + goto exit; + w = Py_BuildValue("(OO)", v, t); + if (w == NULL) + goto exit; + PyErr_SetObject(exc, w); + exit: + Py_XDECREF(t); + Py_XDECREF(v); + Py_XDECREF(w); + Py_XDECREF(line); } /* Interface to the block stack */ @@ -3998,6 +4026,43 @@ get_ref_type(struct compiling *c, char *name) return -1; /* can't get here */ } +/* Helper function for setting lineno and filename */ + +static void +set_error_location(char *filename, int lineno) +{ + PyObject *exc, *v, *tb, *tmp; + + /* add attributes for the line number and filename for the error */ + PyErr_Fetch(&exc, &v, &tb); + PyErr_NormalizeException(&exc, &v, &tb); + tmp = PyInt_FromLong(lineno); + if (tmp == NULL) + PyErr_Clear(); + else { + if (PyObject_SetAttrString(v, "lineno", tmp)) + PyErr_Clear(); + Py_DECREF(tmp); + } + if (filename != NULL) { + tmp = PyString_FromString(filename); + if (tmp == NULL) + PyErr_Clear(); + else { + if (PyObject_SetAttrString(v, "filename", tmp)) + PyErr_Clear(); + Py_DECREF(tmp); + } + + tmp = fetch_program_text(filename, lineno); + if (tmp) { + PyObject_SetAttrString(v, "text", tmp); + Py_DECREF(tmp); + } + } + PyErr_Restore(exc, v, tb); +} + static int symtable_build(struct compiling *c, node *n) { diff --git a/Python/pythonrun.c b/Python/pythonrun.c index 48b875e149b73d..40611b6c5ee19d 100644 --- a/Python/pythonrun.c +++ b/Python/pythonrun.c @@ -693,12 +693,18 @@ parse_syntax_error(PyObject *err, PyObject **message, char **filename, if (!(v = PyObject_GetAttrString(err, "offset"))) goto finally; - hold = PyInt_AsLong(v); - Py_DECREF(v); - v = NULL; - if (hold < 0 && PyErr_Occurred()) - goto finally; - *offset = (int)hold; + if (v == Py_None) { + *offset = -1; + Py_DECREF(v); + v = NULL; + } else { + hold = PyInt_AsLong(v); + Py_DECREF(v); + v = NULL; + if (hold < 0 && PyErr_Occurred()) + goto finally; + *offset = (int)hold; + } if (!(v = PyObject_GetAttrString(err, "text"))) goto finally; @@ -720,6 +726,40 @@ PyErr_Print(void) PyErr_PrintEx(1); } +static void +print_error_text(PyObject *f, int offset, char *text) +{ + char *nl; + if (offset >= 0) { + if (offset > 0 && offset == (int)strlen(text)) + offset--; + for (;;) { + nl = strchr(text, '\n'); + if (nl == NULL || nl-text >= offset) + break; + offset -= (nl+1-text); + text = nl+1; + } + while (*text == ' ' || *text == '\t') { + text++; + offset--; + } + } + PyFile_WriteString(" ", f); + PyFile_WriteString(text, f); + if (*text == '\0' || text[strlen(text)-1] != '\n') + PyFile_WriteString("\n", f); + if (offset == -1) + return; + PyFile_WriteString(" ", f); + offset--; + while (offset > 0) { + PyFile_WriteString(" ", f); + offset--; + } + PyFile_WriteString("^\n", f); +} + void PyErr_PrintEx(int set_sys_last_vars) { @@ -795,36 +835,8 @@ PyErr_PrintEx(int set_sys_last_vars) sprintf(buf, "%d", lineno); PyFile_WriteString(buf, f); PyFile_WriteString("\n", f); - if (text != NULL) { - char *nl; - if (offset > 0 && - offset == (int)strlen(text)) - offset--; - for (;;) { - nl = strchr(text, '\n'); - if (nl == NULL || - nl-text >= offset) - break; - offset -= (nl+1-text); - text = nl+1; - } - while (*text == ' ' || *text == '\t') { - text++; - offset--; - } - PyFile_WriteString(" ", f); - PyFile_WriteString(text, f); - if (*text == '\0' || - text[strlen(text)-1] != '\n') - PyFile_WriteString("\n", f); - PyFile_WriteString(" ", f); - offset--; - while (offset > 0) { - PyFile_WriteString(" ", f); - offset--; - } - PyFile_WriteString("^\n", f); - } + if (text != NULL) + print_error_text(f, offset, text); Py_INCREF(message); Py_DECREF(v); v = message;