[patch][python] Fix python/15747 (provide access to COMPLETE_EXPRESSION

[Phil Muldoon <pmuldoon at redhat dot com>]

This patch adds support for the COMPLETE_EXPRESSION constant for
Python commands.  It also adds a test case for it using fields.

OK?

Cheers,

Phil


2013-09-18  Phil Muldoon  <pmuldoon@redhat.com>
	    
	PR python/15747

	* python/py-cmd.c: Add COMPLETE_EXPRESSION constant.

2013-09-18  Phil Muldoon  <pmuldoon@redhat.com>

	* gdb.python/py-cmd.exp: Add COMPLETE_EXPRESSION tests.
	* gdb.python/py-cmd.c: New File.

2013-09-18  Phil Muldoon  <pmuldoon@redhat.com>

	* gdb.texinfo (Commands In Python): Document COMPLETE_EXPRESSION
	constant.

--

diff --git a/gdb/doc/gdb.texinfo b/gdb/doc/gdb.texinfo
index 60d2877..f277fde 100644
--- a/gdb/doc/gdb.texinfo
+++ b/gdb/doc/gdb.texinfo
@@ -25856,6 +25856,13 @@ command names.
 @item gdb.COMPLETE_SYMBOL
 This constant means that completion should be done using symbol names
 as the source.
+
+@findex COMPLETE_EXPRESSION
+@findex gdb.COMPLETE_EXPRESSION
+@item gdb.COMPLETE_EXPRESSION
+This constant means that completion should be done on expressions.
+Often this means completing on symbol names, but some language
+parsers also have support for completing on field names.
 @end table
 
 The following code snippet shows how a trivial CLI command can be
diff --git a/gdb/python/py-cmd.c b/gdb/python/py-cmd.c
index 8b6252e..56321fa 100644
--- a/gdb/python/py-cmd.c
+++ b/gdb/python/py-cmd.c
@@ -45,6 +45,7 @@ static struct cmdpy_completer completers[] =
   { "COMPLETE_LOCATION", location_completer },
   { "COMPLETE_COMMAND", command_completer },
   { "COMPLETE_SYMBOL", make_symbol_completion_list_fn },
+  { "COMPLETE_EXPRESSION", expression_completer },
 };
 
 #define N_COMPLETERS (sizeof (completers) / sizeof (completers[0]))
diff --git a/gdb/testsuite/gdb.python/py-cmd.c b/gdb/testsuite/gdb.python/py-cmd.c
index e69de29..7f0dc59 100644
--- a/gdb/testsuite/gdb.python/py-cmd.c
+++ b/gdb/testsuite/gdb.python/py-cmd.c
@@ -0,0 +1,29 @@
+/* This testcase is part of GDB, the GNU debugger.
+
+   Copyright 2013 Free Software Foundation, Inc.
+
+   This program is free software; you can redistribute it and/or modify
+   it under the terms of the GNU General Public License as published by
+   the Free Software Foundation; either version 3 of the License, or
+   (at your option) any later version.
+
+   This program is distributed in the hope that it will be useful,
+   but WITHOUT ANY WARRANTY; without even the implied warranty of
+   MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+   GNU General Public License for more details.
+
+   You should have received a copy of the GNU General Public License
+   along with this program.  If not, see  <http://www.gnu.org/licenses/>.  */
+
+struct foo
+{
+  int ij;
+  int bc;
+};
+
+int
+main (void)
+{
+  struct foo bar;
+  return 0;
+}
diff --git a/gdb/testsuite/gdb.python/py-cmd.exp b/gdb/testsuite/gdb.python/py-cmd.exp
index 610fe52..6d12950 100644
--- a/gdb/testsuite/gdb.python/py-cmd.exp
+++ b/gdb/testsuite/gdb.python/py-cmd.exp
@@ -18,15 +18,20 @@
 
 load_lib gdb-python.exp
 
-# Start with a fresh gdb.
+standard_testfile
 
-gdb_exit
-gdb_start
-gdb_reinitialize_dir $srcdir/$subdir
+if { [prepare_for_testing ${testfile}.exp ${testfile} ${srcfile}] } {
+    return -1
+}
 
 # Skip all tests if Python scripting is not enabled.
 if { [skip_python_tests] } { continue }
 
+if ![runto_main] then {
+    fail "Cannot run to main."
+    return 0
+}
+
 # Test a simple command.
 
 gdb_py_test_multiple "input simple command" \
@@ -155,3 +160,32 @@ gdb_test "test_help ugh" "test_cmd output, arg = ugh" "call simple user-defined
 
 # Make sure the command shows up in `help user-defined`.
 gdb_test "help user-defined" "User-defined commands.\[\r\n\]+The commands in this class are those defined by the user.\[\r\n\]+Use the \"define\" command to define a command.\[\r\n\]+\[\r\n\]+List of commands:\[\r\n\]+\[\r\n\]+test_help -- Docstring\[\r\n\]+\[\r\n\]+Type \"help\" followed by command name for full documentation.\[\r\n\]+Type \"apropos word\" to search for commands related to \"word\".\[\r\n\]+Command name abbreviations are allowed if unambiguous.\[\r\n\]+" "see user-defined command in `help user-defined`"
+
+# Test expression completion on fields
+gdb_py_test_multiple "expression completion command" \
+  "python" "" \
+  "class expr_test (gdb.Command):" "" \
+  "  def __init__ (self):" "" \
+  "    super (expr_test, self).__init__ (\"expr_test\", gdb.COMMAND_USER, gdb.COMPLETE_EXPRESSION)" "" \
+  "  def invoke (self, arg, from_tty):" "" \
+  "    print (\"invoked on = %s\" % arg)" "" \
+  "expr_test ()" "" \
+  "end" ""
+
+
+gdb_test "complete expr_test bar\." \
+    "expr_test bar\.bc.*expr_test bar\.ij.*" \
+    "Test completion through complete command"
+
+set test "complete 'expr_test bar.i'"
+send_gdb "expr_test bar\.i\t\t"
+gdb_test_multiple "" "$test" {
+    -re "expr_test bar\.ij \\\x07$" {
+	send_gdb "\n"
+	gdb_test_multiple "" $test {
+	    -re "invoked on = bar.ij.*$gdb_prompt $" {
+		pass "$test"
+	    }
+	}
+    }
+}