# Copyright 2017-2020 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/>.

# This file is part of the gdb testsuite.

# Any variable or procedure in the namespace whose name starts with
# "_" is private to the module.  Do not use these.

namespace eval completion {
    variable bell_re "\\\x07"

    # List of all quote chars.
    variable all_quotes_list {"'" "\""}

    # List of all quote chars, including no-quote at all.
    variable maybe_quoted_list {"" "'" "\""}

    variable keyword_list {"if" "task" "thread"}

    variable explicit_opts_list \
	{"-function" "-label" "-line" "-qualified" "-source"}
}

# Make a regular expression that matches a TAB completion list.

proc make_tab_completion_list_re { completion_list } {
    # readline separates the completion columns that fit on the same
    # line with whitespace.  Since we're testing under "set width
    # unlimited", all completions will be printed on the same line.
    # The amount of whitespace depends on the length of the widest
    # completion.  We could compute that here and expect the exact
    # number of ws characters between each completion match, but to
    # keep it simple, we accept any number of characters.
    set ws " +"

    set completion_list_re ""
    foreach c $completion_list {
	append completion_list_re [string_to_regexp $c]
	append completion_list_re $ws
    }
    append completion_list_re $ws

    return $completion_list_re
}

# Make a regular expression that matches a "complete" command
# completion list.  CMD_PREFIX is the command prefix added to each
# completion match.

proc make_cmd_completion_list_re { cmd_prefix completion_list start_quote_char end_quote_char } {

    set completion_list_re ""
    foreach c $completion_list {
	# The command prefix is included in all completion matches.
	append completion_list_re [string_to_regexp $cmd_prefix$start_quote_char$c$end_quote_char]
	append completion_list_re "\r\n"
    }

    return $completion_list_re
}

# Clear the input line.

proc clear_input_line { test } {
    global gdb_prompt

    send_gdb "\003"
    gdb_test_multiple "" "$test (clearing input line)" {
	-re "Quit\r\n$gdb_prompt $" {
	}
    }
}

# Test that completing LINE with TAB completes to nothing.

proc test_gdb_complete_tab_none { line } {
    set line_re [string_to_regexp $line]

    set test "tab complete \"$line\""
    send_gdb "$line\t"
    gdb_test_multiple "" "$test" {
	-re "^$line_re$completion::bell_re$" {
	    pass "$test"
	}
    }

    clear_input_line $test
}

# Test that completing INPUT_LINE with TAB completes to
# COMPLETE_LINE_RE.  APPEND_CHAR_RE is the character expected to be
# appended after EXPECTED_OUTPUT.  Normally that's a whitespace, but
# in some cases it's some other character, like a colon.

proc test_gdb_complete_tab_unique { input_line complete_line_re append_char_re } {

    set test "tab complete \"$input_line\""
    send_gdb "$input_line\t"
    set res 1
    gdb_test_multiple "" "$test" {
	-re "^$complete_line_re$append_char_re$" {
	    pass "$test"
	}
	timeout {
	    fail "$test (timeout)"
	    set res -1
	}
    }

    clear_input_line $test
    return $res
}

# Test that completing INPUT_LINE with TAB completes to "INPUT_LINE +
# ADD_COMPLETED_LINE" and that it displays the completion matches in
# COMPLETION_LIST.  If MAX_COMPLETIONS then we expect the completion
# to hit the max-completions limit.

proc test_gdb_complete_tab_multiple { input_line add_completed_line \
					  completion_list {max_completions 0}} {
    global gdb_prompt

    set input_line_re [string_to_regexp $input_line]
    set add_completed_line_re [string_to_regexp $add_completed_line]

    set expected_re [make_tab_completion_list_re $completion_list]

    if {$max_completions} {
	append expected_re "\r\n"
	append expected_re \
	    "\\*\\*\\* List may be truncated, max-completions reached\\. \\*\\*\\*"
    }

    set test "tab complete \"$input_line\""
    send_gdb "$input_line\t"
    gdb_test_multiple "" "$test (first tab)" {
	-re "^${input_line_re}${completion::bell_re}$add_completed_line_re$" {
	    send_gdb "\t"
	    # If we auto-completed to an ambiguous prefix, we need an
	    # extra tab to show the matches list.
	    if {$add_completed_line != ""} {
		send_gdb "\t"
		set maybe_bell ${completion::bell_re}
	    } else {
		set maybe_bell ""
	    }
	    gdb_test_multiple "" "$test (second tab)" {
		-re "^${maybe_bell}\r\n$expected_re\r\n$gdb_prompt " {
		    gdb_test_multiple "" "$test (second tab)" {
			-re "^$input_line_re$add_completed_line_re$" {
			    pass "$test"
			}
		    }
		}
	    }
	}
    }

    clear_input_line $test
}

# Test that completing LINE with the complete command completes to
# nothing.

proc test_gdb_complete_cmd_none { line } {
    gdb_test_no_output "complete $line" "cmd complete \"$line\""
}

# Test that completing LINE with the complete command completes to
# COMPLETE_LINE_RE.

proc test_gdb_complete_cmd_unique { input_line complete_line_re } {
    global gdb_prompt

    set cmd "complete $input_line"
    set cmd_re [string_to_regexp $cmd]
    set test "cmd complete \"$input_line\""
    gdb_test_multiple $cmd $test {
	-re "^$cmd_re\r\n$complete_line_re\r\n$gdb_prompt $" {
	    pass $test
	}
    }
}

# Test that completing "CMD_PREFIX + COMPLETION_WORD" with the
# complete command displays the COMPLETION_LIST completion list.  Each
# entry in the list should be prefixed by CMD_PREFIX.  If
# MAX_COMPLETIONS then we expect the completion to hit the
# max-completions limit.

proc test_gdb_complete_cmd_multiple { cmd_prefix completion_word completion_list {start_quote_char ""} {end_quote_char ""} {max_completions 0}} {
    global gdb_prompt

    set expected_re [make_cmd_completion_list_re $cmd_prefix $completion_list $start_quote_char $end_quote_char]

    if {$max_completions} {
	set cmd_prefix_re [string_to_regexp $cmd_prefix]
	append expected_re \
	    "$cmd_prefix_re \\*\\*\\* List may be truncated, max-completions reached\\. \\*\\*\\*.*\r\n"
    }

    set cmd_re [string_to_regexp "complete $cmd_prefix$completion_word"]
    set test "cmd complete \"$cmd_prefix$completion_word\""
    gdb_test_multiple "complete $cmd_prefix$completion_word" $test {
	-re "^$cmd_re\r\n$expected_re$gdb_prompt $" {
	    pass $test
	}
    }
}

# Test that completing LINE completes to nothing.

proc test_gdb_complete_none { input_line } {
    if { [readline_is_used] } {
	test_gdb_complete_tab_none $input_line
    }
    test_gdb_complete_cmd_none $input_line
}

# Test that completing INPUT_LINE completes to COMPLETE_LINE_RE.
#
# APPEND_CHAR is the character expected to be appended after
# EXPECTED_OUTPUT when TAB completing.  Normally that's a whitespace,
# but in some cases it's some other character, like a colon.
#
# If MAX_COMPLETIONS is true, then we expect the completion to hit the
# max-completions limit.  Since we're expecting a unique completion
# match, this will only be visible in the "complete" command output.
# Tab completion will just auto-complete the only match and won't
# display a match list.
#
# Note: usually it's more convenient to pass a literal string instead
# of a regular expression (as COMPLETE_LINE_RE).  See
# test_gdb_complete_unique below.

proc test_gdb_complete_unique_re { input_line complete_line_re {append_char " "} {max_completions 0}} {
    set append_char_re [string_to_regexp $append_char]
    if { [readline_is_used] } {
	if { [test_gdb_complete_tab_unique $input_line $complete_line_re \
		  $append_char_re] == -1 } {
	    return -1
	}
    }

    # Trim INPUT_LINE and COMPLETE LINE, for the case we're completing
    # a command with leading whitespace.  Leading command whitespace
    # is discarded by GDB.
    set input_line [string trimleft $input_line]
    set expected_output_re [string trimleft $complete_line_re]
    if {$append_char_re != " "} {
	append expected_output_re $append_char_re
    }
    if {$max_completions} {
	set max_completion_reached_msg \
	    "*** List may be truncated, max-completions reached. ***"
	set input_line_re \
	    [string_to_regexp $input_line]
	set max_completion_reached_msg_re \
	    [string_to_regexp $max_completion_reached_msg]

	append expected_output_re \
	    "\r\n$input_line_re $max_completion_reached_msg_re"
    }

    test_gdb_complete_cmd_unique $input_line $expected_output_re
    return 1
}

# Like TEST_GDB_COMPLETE_UNIQUE_RE, but COMPLETE_LINE is a string, not
# a regular expression.

proc test_gdb_complete_unique { input_line complete_line {append_char " "} {max_completions 0}} {
    set complete_line_re [string_to_regexp $complete_line]
    test_gdb_complete_unique_re $input_line $complete_line_re $append_char $max_completions
}

# Test that completing "CMD_PREFIX + COMPLETION_WORD" adds
# ADD_COMPLETED_LINE to the input line, and that it displays
# COMPLETION_LIST as completion match list.  COMPLETION_WORD is the
# completion word.  If MAX_COMPLETIONS then we expect the completion
# to hit the max-completions limit.

proc test_gdb_complete_multiple {
  cmd_prefix completion_word add_completed_line completion_list
  {start_quote_char ""} {end_quote_char ""} {max_completions 0}
} {
    if { [readline_is_used] } {
      test_gdb_complete_tab_multiple "$cmd_prefix$completion_word" $add_completed_line $completion_list $max_completions
    }
    test_gdb_complete_cmd_multiple $cmd_prefix $completion_word $completion_list $start_quote_char $end_quote_char $max_completions
}

# Test that all the substring prefixes of INPUT from [0..START) to
# [0..END) complete to COMPLETION_RE (a regular expression).  If END
# is ommitted, default to the length of INPUT.

proc test_complete_prefix_range_re {input completion_re start {end -1}} {
    if {$end == -1} {
	set end [string length $input]
    }

    set timeouts 0
    set max_timeouts 3
    for {set i $start} {$i < $end} {incr i} {
	set line [string range $input 0 $i]
	set res [test_gdb_complete_unique_re "$line" $completion_re]
	if { $res == -1 } {
	    incr timeouts
	} else {
	    if { $timeouts > 0 } {
		set timeouts 0
	    }
	}
	if { $timeouts == $max_timeouts } {
	    verbose -log "Consecutive timeouts in test_complete_prefix_range_re, giving up"
	    break
	}
    }
}

# Test that all the substring prefixes of COMPLETION from [0..START)
# to [0..END) complete to COMPLETION.  If END is ommitted, default to
# the length of COMPLETION.

proc test_complete_prefix_range {completion start {end -1}} {
    set completion_re [string_to_regexp $completion]
    test_complete_prefix_range_re $completion $completion_re $start $end
}

# Find NEEDLE in HAYSTACK and return the index _after_ NEEDLE.  E.g.,
# searching for "(" in "foo(int)" returns 4, which would be useful if
# you want to find the "(" to try completing "foo(".

proc index_after {needle haystack} {
    set start [string first $needle $haystack]
    if {$start == -1} {
	error "could not find \"$needle\" in \"$haystack\""
    }
    return [expr $start + [string length $needle]]
}

# Create a breakpoint using BREAK_COMMAND, and return the number
# of locations found.

proc completion::_create_bp {break_command} {
    global gdb_prompt
    global decimal hex

    set found_locations -1

    set test "set breakpoint"
    gdb_test_multiple "$break_command" $test {
	-re "\\\(\($decimal\) locations\\\)\r\n$gdb_prompt $" {
	    set found_locations "$expect_out(1,string)"
	}
	-re "Breakpoint $decimal at $hex: file .*, line .*$gdb_prompt $" {
	    set found_locations 1
	}
	-re "Make breakpoint pending on future shared library load.*y or .n.. $" {
	    send_gdb "n\n"
	    gdb_test_multiple "" "$test (prompt)" {
		-re "$gdb_prompt $" {
		}
	    }
	    set found_locations 0
	}
	-re "invalid explicit location argument, \[^\r\n\]*\r\n$gdb_prompt $" {
	    set found_locations 0
	}
	-re "Function \[^\r\n\]* not defined in \[^\r\n\]*\r\n$gdb_prompt $" {
	    set found_locations 0
	}
    }
    return $found_locations
}

# Return true if lists A and B have the same elements.  Order of
# elements does not matter.

proc completion::_leq {a b} {
    return [expr {[lsort $a] eq [lsort $b]}]
}

# Check that trying to create a breakpoint using BREAK_COMMAND fails.

proc check_setting_bp_fails {break_command} {
    with_test_prefix "\"$break_command\" creates no bp locations" {
	set found_locations [completion::_create_bp $break_command]
	gdb_assert {$found_locations == 0} "matches"
	if {$found_locations != 0} {
	    delete_breakpoints
	}
    }
}

# Check that creating the breakpoint using BREAK_COMMAND finds the
# same breakpoint locations as completing BREAK_COMMAND.
# COMPLETION_LIST is the expected completion match list.

proc check_bp_locations_match_list {break_command completion_list} {
    global gdb_prompt
    global hex

    with_test_prefix "compare \"$break_command\" completion list with bp location list" {
	set num_locations [completion::_create_bp $break_command]

	set found_list ""

	set any "\[^\r\n\]*"

	gdb_test_multiple "info breakpoint \$bpnum" "info breakpoint" {
	    -re "in \(\[^\r\n\]*\) at " {
		# A function location.
		set found_location "$expect_out(1,string)"
		lappend found_list $found_location
		exp_continue
	    }
	    -re "breakpoint${any}keep${any}y${any}$hex\[ \t]*\(${any}\)\r\n" {
		# A label location.
		set found_location "$expect_out(1,string)"
		lappend found_list $found_location
		exp_continue
	    }
	    -re "$gdb_prompt $" {
	    }
	}

	gdb_assert {[completion::_leq $found_list $completion_list]} "matches"

	delete_breakpoints
    }
}

# Build linespec and explicit locations out of all the combinations of
# SOURCES, FUNCTIONS and LABELS, with all combinations of possible
# quoting and whitespace around separators, and run BODY_LINESPEC and
# BODY_EXPLICIT in the context of the caller for each combination.  A
# variable named "location" is set in the callers context with the
# currently iterated location.

proc foreach_location_functions { sources functions body_linespec body_explicit } {
    upvar source source
    upvar function function
    upvar source_sep source_sep
    upvar location location

    foreach source $sources {
	# Test with and without source quoting.
	foreach sqc $completion::maybe_quoted_list {
	    if {$source == "" && $sqc != ""} {
		# Invalid combination.
		continue
	    }

	    # Test with and without function quoting.
	    foreach fqc $completion::maybe_quoted_list {
		# Test known and unknown functions.
		foreach function $functions {
		    # Linespec version.  Test with and without spacing
		    # after the source/colon colon separator.
		    foreach source_sep {"" ":" ": "} {
			# Skip invalid combinations.
			if {$source == "" && $source_sep != ""} {
			    continue
			}
			if {$source != "" && $source_sep == ""} {
			    continue
			}

			set location "${sqc}${source}${sqc}${source_sep}${fqc}$function${fqc}"
			uplevel 1 $body_linespec
		    }

		    # Explicit locations version.
		    if {$source != ""} {
			set loc_src "-source ${sqc}${source}${sqc} "
		    } else {
			set loc_src ""
		    }

		    set location "${loc_src}-function ${fqc}$function${fqc}"
		    uplevel 1 $body_explicit
		}
	    }
	}
    }
}

# Same as foreach_locations_functions, but also iterate over
# combinations of labels.
proc foreach_location_labels { sources functions labels body_linespec body_explicit } {
    upvar source source
    upvar function function
    upvar label label
    upvar source_sep source_sep
    upvar label_sep label_sep
    upvar location location

    # Test both with a known source file and without a source file
    # component.
    foreach_location_functions \
	$sources \
	$functions \
	{
	    # Linespec version.  Test various spacing around the label
	    # colon separator.
	    set saved_location ${location}
	    foreach label_sep {":" " :" ": " " : "} {
		# Test both known and unknown label.
		foreach label $labels {
		    set location "${saved_location}${label_sep}$label"
		    uplevel 1 $body_linespec
		}
	    }
	} \
	{
	    # Explicit locations version.
	    set saved_location ${location}
	    foreach label $labels {
		set location "${saved_location} -label $label"
		uplevel 1 $body_explicit
	    }
	}
}

# Check that completion of INPUT_LINE results in GDB completing on all
# command names.
proc test_gdb_completion_offers_commands {input_line} {
    global gdb_prompt

    # There are two many commands to usefully check here.  So we force
    # max-completions to 2, and check if those 2 come out.

    # Save current max-completions.
    set max_completions 0
    set test "show max-completions"
    gdb_test_multiple $test $test {
	-re "Maximum number of completion candidates is (.*)\\.\r\n$gdb_prompt $" {
	    set max_completions $expect_out(1,string)
	}
    }

    # Force showing two commands.
    gdb_test_no_output "set max-completions 2" ""

    test_gdb_complete_multiple $input_line "" "" {
	"!"
	"+"
    } "" "" 1

    # Restore.
    gdb_test_no_output "set max-completions $max_completions" ""
}