# Copyright 2024-2025 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/>.

# If a user uses 'Ctrl+d' to exit from a secondary prompt, then
# readline can get stuck thinking that an EOF has arrived.  As a
# consequence of this readline will output an extra newline every time
# that it exits bracketed-paste-mode (which is done after every line
# of input).  The result is the user will see some unexpected blank
# lines in the output.

standard_testfile

if { [prepare_for_testing "failed to prepare" $testfile $srcfile] } {
    return -1
}

# The fix for this issue relies on GDB being able to adjust the EOF
# flag state within readline.  Access to this state was added for
# readline 8.2, but was also backported to out internal readline.  If
# this feature is not available then this test might not pass.
if { ![readline_supports_eof_flag] } {
    unsupported "readline is not eof flag aware"
    return -1
}

# Create a breakpoint then issue the 'commands' commands.  When the
# secondary prompt is displayed, use Ctrl+d to send EOF to readline
# and cancel the input.
#
# Then check that readline is not stuck thinking that an EOF has
# arrived.  If it is then GDB will start displaying extra blank lines
# after each line of input.
proc run_test {} {
    clean_restart $::binfile

    gdb_breakpoint main

    # Issue the 'commands' command, and wait for the secondary prompt
    # to be displayed.
    gdb_test_multiple "commands" "start b/p commands" {
	-re "Type commands for breakpoint\\(s\\) 1, one per line\\.\r\n" {
	    exp_continue
	}
	-re "^End with a line saying just \"end\"\\.\r\n" {
	    exp_continue
	}
	-re "^\[^\r\n\]*>$" {
	    pass $gdb_test_name
	}
    }

    # Send Ctrl+d to GDB and wait for the 'quit' message, and then for
    # the GDB prompt to be displayed.
    #
    # As this test runs (sometimes) with bracketed-paste-mode on then
    # we need to accept a control sequence before the prompt.  This
    # control sequence can contain '\r', which is why we only check
    # for '\n' here, which is different than what we do in the rest of
    # the testsuite, where we usually check for '\r\n' together.
    send_gdb "\004"
    gdb_test_multiple "" "quit b/p commands" {
	-re "^quit\r\n\[^\n\]*$::gdb_prompt $" {
	    pass $gdb_test_name
	}
    }

    # Now issue any other command.  If readline is stuck in EOF mode
    # (thinking that an EOF has just arrived), then we'll see an extra
    # blank line after the command, and before any command output.
    #
    # As described above we scan for '\n' only in some patterns here
    # as we're allowing for a control sequence that might include
    # '\r'.
    gdb_test_multiple "show architecture" "check for excessive blank lines" {
	-re "^show architecture\r\n" {
	    exp_continue
	}
	-re "^\[^\n\]*The target architecture is set to \[^\r\n\]+\\.\r\n\[^\n\]*$::gdb_prompt $" {
	    pass $gdb_test_name
	}
	-re "^\[^\n\]*\nThe target architecture is set to \[^\r\n\]+\\.\r\n\[^\n\]*$::gdb_prompt" {
	    fail $gdb_test_name
	}
    }
}

# Run the test in various different terminal modes.
with_test_prefix "default" {
    run_test
}

save_vars { env(TERM) } {
    setenv TERM ansi

    with_test_prefix "with non-dump terminal" {
	run_test

	save_vars { env(INPUTRC) } {

	    # Create an inputrc file that turns bracketed paste mode
	    # on.  This is usually turned off (see lib/gdb.exp), but
	    # for the next test we want to see what happens with this
	    # on.
	    set inputrc [standard_output_file inputrc]
	    set fd [open "$inputrc" w]
	    puts $fd "set enable-bracketed-paste on"
	    close $fd

	    setenv INPUTRC "$inputrc"
	    with_test_prefix "with bracketed-paste-mode on" {
		run_test
	    }
	}
    }
}