Re: [PATCH] gdb: allow specifying multiple filters when running selftests

[Simon Marchi <simon.marchi@polymtl.ca>]

On 2020-08-13 10:06 a.m., Tom Tromey wrote:
>>>>>> "Simon" == Simon Marchi via Gdb-patches <gdb-patches@sourceware.org> writes:
> 
> Simon> +  selftests::run_tests (gdb::array_view<char *> (argv.get (), argv.count ()));
> 
> I think it would be good to add a method to gdb_argv that returns an
> array view.

Hmm do you think it will happen often enough that we pass the parsed arguments straight to a
function taking an array view?

In any case, it's not difficult to do.  Did you mean a simple method like the patch below, or
a conversion operator that could be implemented like this, to be able to transparently pass
a gdb_argv as an array_view?

  using char_ptr_array_view = gdb::array_view<char *>;
  operator char_ptr_array_view()
  {
    return gdb::array_view<char *> (this->get (), this->count ());
  }

Personally I prefer things to be a bit more explicit, otherwise there's a bit too much hidden
magic.


From 79a9b29c1f08382ac790f2661fff55eade4d0174 Mon Sep 17 00:00:00 2001
From: Simon Marchi <simon.marchi@polymtl.ca>
Date: Thu, 13 Aug 2020 10:28:41 -0400
Subject: [PATCH] gdb: add gdb_argv::as_array_view method

Change-Id: I0645037613ed6549aabe60f14a36f3494513b177
---
 gdb/maint.c |  2 +-
 gdb/utils.c | 26 ++++++++++++++++++++++++++
 gdb/utils.h |  8 ++++++++
 3 files changed, 35 insertions(+), 1 deletion(-)

diff --git a/gdb/maint.c b/gdb/maint.c
index fd37acce5226..3368769ad96f 100644
--- a/gdb/maint.c
+++ b/gdb/maint.c
@@ -1042,7 +1042,7 @@ maintenance_selftest (const char *args, int from_tty)
 {
 #if GDB_SELF_TEST
   gdb_argv argv (args);
-  selftests::run_tests (gdb::array_view<char *> (argv.get (), argv.count ()));
+  selftests::run_tests (argv.as_array_view ());
 #else
   printf_filtered (_("\
 Selftests have been disabled for this build.\n"));
diff --git a/gdb/utils.c b/gdb/utils.c
index 102db28787fb..fb1308ac9ae3 100644
--- a/gdb/utils.c
+++ b/gdb/utils.c
@@ -2991,6 +2991,31 @@ gdb_realpath_tests ()
   gdb_realpath_check_trailer ("", "");
 }

+/* Test the gdb_argv::as_array_view method.  */
+
+static void
+gdb_argv_as_array_view_test ()
+{
+  {
+    gdb_argv argv;
+
+    gdb::array_view<char *> view = argv.as_array_view ();
+
+    SELF_CHECK (view.data () == nullptr);
+    SELF_CHECK (view.size () == 0);
+  }
+  {
+    gdb_argv argv ("une bonne 50");
+
+    gdb::array_view<char *> view = argv.as_array_view ();
+
+    SELF_CHECK (view.size () == 3);
+    SELF_CHECK (strcmp (view[0], "une") == 0);
+    SELF_CHECK (strcmp (view[1], "bonne") == 0);
+    SELF_CHECK (strcmp (view[2], "50") == 0);
+  }
+}
+
 #endif /* GDB_SELF_TEST */

 /* Allocation function for the libiberty hash table which uses an
@@ -3489,5 +3514,6 @@ When set, debugging messages will be marked with seconds and microseconds."),

 #if GDB_SELF_TEST
   selftests::register_test ("gdb_realpath", gdb_realpath_tests);
+  selftests::register_test ("gdb_argv_array_view", gdb_argv_as_array_view_test);
 #endif
 }
diff --git a/gdb/utils.h b/gdb/utils.h
index 3434ff1caa25..9a235b963272 100644
--- a/gdb/utils.h
+++ b/gdb/utils.h
@@ -22,6 +22,7 @@
 #define UTILS_H

 #include "exceptions.h"
+#include "gdbsupport/array-view.h"
 #include "gdbsupport/scoped_restore.h"
 #include <chrono>

@@ -210,6 +211,13 @@ class gdb_argv
     return m_argv[arg];
   }

+  /* Return the arguments array as an array view.  */
+
+  gdb::array_view<char *> as_array_view ()
+  {
+    return gdb::array_view<char *> (this->get (), this->count ());
+  }
+
   /* The iterator type.  */

   typedef char **iterator;
-- 
2.28.0