Patch: add gdb.parse_and_eval

Tom Tromey
2009-06-11T20:49:28Z

This adds the function "gdb.parse_and_eval" to the Python API.
This is handy when writing new commands, among other things.

It needs a doc review.

Tom

2009-06-11 Tom Tromey <tromey@redhat.com>

* python/python.c (gdbpy_parse_and_eval): New function.
(GdbMethods): Add "parse_and_eval".

2009-06-11 Tom Tromey <tromey@redhat.com>

* gdb.texinfo (Basic Python): Document gdb.parse_and_eval.

2009-06-11 Tom Tromey <tromey@redhat.com>

* gdb.python/python-value.exp (test_parse_and_eval): New
function.

Index: doc/gdb.texinfo
===================================================================
RCS file: /cvs/src/src/gdb/doc/gdb.texinfo,v
retrieving revision 1.599
diff -u -r1.599 gdb.texinfo
--- doc/gdb.texinfo 11 Jun 2009 11:57:46 -0000 1.599
+++ doc/gdb.texinfo 11 Jun 2009 20:48:30 -0000
@@ -18611,6 +18611,13 @@
@code{gdb.Value} (@pxref{Values From Inferior}).
@end defun

+@findex gdb.parse_and_eval
+@defun parse_and_eval expression
+Parse @var{expression} as an expression in the current language,
+evaluate it, and return the result as a @code{gdb.Value}.
+@var{expression} must be a string.
+@end defun
+
@findex gdb.write
@defun write string
Print a string to @value{GDBN}'s paginated standard output stream.
Index: python/python.c
===================================================================
RCS file: /cvs/src/src/gdb/python/python.c,v
retrieving revision 1.18
diff -u -r1.18 python.c
--- python/python.c 28 May 2009 16:49:55 -0000 1.18
+++ python/python.c 11 Jun 2009 20:48:30 -0000
@@ -275,6 +275,26 @@
Py_RETURN_NONE;
}

+/* Parse a string and evaluate it as an expression. */
+static PyObject *
+gdbpy_parse_and_eval (PyObject *self, PyObject *args)
+{
+ char *expr_str;
+ struct value *result = NULL;
+ volatile struct gdb_exception except;
+
+ if (!PyArg_ParseTuple (args, "s", &expr_str))
+ return NULL;
+
+ TRY_CATCH (except, RETURN_MASK_ALL)
+ {
+ result = parse_and_eval (expr_str);
+ }
+ GDB_PY_HANDLE_EXCEPTION (except);
+
+ return value_to_value_object (result);
+}
+
\f

/* Printing. */
@@ -635,6 +655,11 @@
"lookup_type (name [, block]) -> type\n\
Return a Type corresponding to the given name." },

+ { "parse_and_eval", gdbpy_parse_and_eval, METH_VARARGS,
+ "parse_and_eval (String) -> Value.\n\
+Parse String as an expression, evaluate it, and return the result as a Value."
+ },
+
{ "write", gdbpy_write, METH_VARARGS,
"Write a string using gdb's filtered stream." },
{ "flush", gdbpy_flush, METH_NOARGS,
Index: testsuite/gdb.python/python-value.exp
===================================================================
RCS file: /cvs/src/src/gdb/testsuite/gdb.python/python-value.exp,v
retrieving revision 1.8
diff -u -r1.8 python-value.exp
--- testsuite/gdb.python/python-value.exp 28 May 2009 00:47:20 -0000 1.8
+++ testsuite/gdb.python/python-value.exp 11 Jun 2009 20:48:32 -0000
@@ -273,6 +273,17 @@
"print value's type"
}

+# A few tests of gdb.parse_and_eval.
+proc test_parse_and_eval {} {
+ gdb_test "python print gdb.parse_and_eval ('23')" "23" \
+ "parse_and_eval constant test"
+ gdb_test "python print gdb.parse_and_eval ('5 + 7')" "12" \
+ "parse_and_eval simple expression test"
+ gdb_test "python print type(gdb.parse_and_eval ('5 + 7'))" \
+ ".type 'gdb.Value'."\
+ "parse_and_eval type test"
+}
+
# Start with a fresh gdb.

gdb_exit
@@ -293,6 +304,7 @@
test_value_boolean
test_value_compare
test_objfiles
+test_parse_and_eval

# The following tests require execution.