[PATCH 01/15] gdb/testsuite: extend gdb.tui/tui-layout.exp test script

[Andrew Burgess <aburgess@redhat.com>]

In passing I noticed that the gdb.tui/tui-layout.exp test script was a
little strange, it tests the layout command multiple times, but never
sets up our ANSI terminal emulator, so every layout command fails with
a message about the terminal lacking the required abilities.

It turns out that this was caused by this commit:

  commit 9162a27c5f5828240b53379d735679e2a69a9f41
  Date:   Tue Nov 13 11:59:03 2018 -0700

      Change gdb test suite's TERM setting

This was when we changed the testsuite to set the TERM environment
variable to "dumb" by default.

After this, any tui test that didn't set the terminal mode back to
'ansi' would fail to activate tui mode.

For the tui-layout.exp test it just so happens that the test patterns
are generic enough that the test continued to pass, even after this
change.

In this commit I have updated the test so we now check the layout
command both with a 'dumb' terminal and with the 'ansi' terminal.
When testing with the 'ansi' terminal, I have some limited validation
that GDB correctly entered tui mode.

I figured that it is probably worth having at least one test in the
test suite that deliberately tries to enter tui mode in a dumb
terminal, it would be sad if we one day managed to break GDB such that
this caused a crash, and never noticed.
---
 gdb/testsuite/gdb.tui/tui-layout.exp | 57 ++++++++++++++++++++++------
 1 file changed, 46 insertions(+), 11 deletions(-)

diff --git a/gdb/testsuite/gdb.tui/tui-layout.exp b/gdb/testsuite/gdb.tui/tui-layout.exp
index 97734cf7b68..e69760193c5 100644
--- a/gdb/testsuite/gdb.tui/tui-layout.exp
+++ b/gdb/testsuite/gdb.tui/tui-layout.exp
@@ -16,6 +16,8 @@
 # Minimal testcase that just checks that the various "layout $foo"
 # commands do not cause gdb to crash.
 
+tuiterm_env
+
 standard_testfile
 
 if {[prepare_for_testing "failed to prepare" ${testfile} ${srcfile}]} {
@@ -26,13 +28,33 @@ if {[skip_tui_tests]} {
     return
 }
 
-# Test one layout command.  EXECUTION indicates whether to activate
-# the layout with or without execution.
+# Run one test of the 'layout' command, selecting LAYOUT_NAME.
+#
+# TERMINAL should be either 'dumb' or 'ansi'.  When TERMINAL is 'dumb'
+# then GDB is started in a terminal that does not support tui mode, in
+# this case the layout command is expected to fail.
+#
+# When TERMINAL is 'ansi' then GDB is started using our emulated ANSI
+# terminal, and the layout command is expected to succeed.
+#
+# When EXECUTION is true then a call to runto_main is used, otherwise
+# this call is skipped and the inferior is left in whatever state it
+# happens to be in after a call to clean_restart.
 
-proc test_layout {layout execution} {
+proc test_layout_or_focus {layout_name terminal execution} {
     global binfile gdb_prompt
 
-    clean_restart $binfile
+    set dumb_terminal [string equal $terminal "dumb"]
+
+    if {$dumb_terminal} {
+	clean_restart $binfile
+    } else {
+	Term::clean_restart 24 80 $binfile
+	if {![Term::prepare_for_tui]} {
+	    unsupported "TUI not supported"
+	    return
+	}
+    }
 
     if {$execution} {
 	if {![runto_main]} {
@@ -40,16 +62,29 @@ proc test_layout {layout execution} {
 	}
     }
 
-    set test "layout command"
-    gdb_test_multiple "layout $layout" $test {
-	-re "$gdb_prompt $" {
-	    pass $test
+    if {$dumb_terminal} {
+	gdb_test "layout $layout_name" \
+	    "Cannot enable the TUI: terminal doesn't support cursor addressing \\\[TERM=dumb\\\]"
+    } else {
+	Term::command_no_prompt_prefix "layout $layout_name"
+	if {$layout_name == "asm"} {
+	    Term::check_box "asm box" 0 0 80 15
+	} elseif {$layout_name == "reg"} {
+	    Term::check_box "reg box" 0 0 80 8
+	    Term::check_box "src box" 0 7 80 8
+	} elseif {$layout_name == "src"} {
+	    Term::check_box "src box" 0 0 80 15
+	} elseif {$layout_name == "split"} {
+	    Term::check_box "src box" 0 0 80 8
+	    Term::check_box "asm box" 0 7 80 8
 	}
     }
 }
 
-foreach_with_prefix execution {0 1} {
-    foreach_with_prefix layout {"asm" "reg" "src" "split"} {
-	test_layout $layout $execution
+foreach_with_prefix terminal {ansi dumb} {
+    foreach_with_prefix execution {false true} {
+	foreach_with_prefix layout {"asm" "reg" "src" "split"} {
+	    test_layout_or_focus $layout $terminal $execution
+	}
     }
 }
-- 
2.25.4