# This file is a part of Julia. License is MIT: https://julialang.org/license

# For curmod_*
include("testenv.jl")

# REPL tests
isdefined(Main, :TestHelpers) || @eval Main include(joinpath(dirname(@__FILE__), "TestHelpers.jl"))
using TestHelpers
import Base: REPL, LineEdit

function fake_repl(f)
    # Use pipes so we can easily do blocking reads
    # In the future if we want we can add a test that the right object
    # gets displayed by intercepting the display
    stdin = Pipe()
    stdout = Pipe()
    stderr = Pipe()
    Base.link_pipe(stdin, julia_only_read=true, julia_only_write=true)
    Base.link_pipe(stdout, julia_only_read=true, julia_only_write=true)
    Base.link_pipe(stderr, julia_only_read=true, julia_only_write=true)

    repl = Base.REPL.LineEditREPL(TestHelpers.FakeTerminal(stdin.out, stdout.in, stderr.in))
    f(stdin.in, stdout.out, repl)
    t = @async begin
        close(stdin.in)
        close(stdout.in)
        close(stderr.in)
    end
    @test read(stderr.out, String) == ""
    #display(read(stdout.out, String))
    wait(t)
    nothing
end

# Writing ^C to the repl will cause sigint, so let's not die on that
ccall(:jl_exit_on_sigint, Void, (Cint,), 0)
# These are integration tests. If you want to unit test test e.g. completion, or
# exact LineEdit behavior, put them in the appropriate test files.
# Furthermore since we are emulating an entire terminal, there may be control characters
# in the mix. If verification needs to be done, keep it to the bare minimum. Basically
# this should make sure nothing crashes without depending on how exactly the control
# characters are being used.
fake_repl() do stdin_write, stdout_read, repl
    repl.specialdisplay = Base.REPL.REPLDisplay(repl)
    repl.history_file = false

    repltask = @async begin
        Base.REPL.run_repl(repl)
    end

    global inc = false
    global b = Condition()
    global c = Condition()
    let cmd = "\"Hello REPL\""
        write(stdin_write, "$(curmod_prefix)inc || wait($(curmod_prefix)b); r = $cmd; notify($(curmod_prefix)c); r\r")
    end
    inc = true
    notify(b)
    wait(c)

    # Latex completions
    write(stdin_write, "\x32\\alpha\t")
    readuntil(stdout_read, "α")
    # Bracketed paste in search mode
    write(stdin_write, "\e[200~paste here ;)\e[201~")
    # Abort search (^C)
    write(stdin_write, '\x03')
    # Test basic completion in main mode
    write(stdin_write, "Base.REP\t")
    readuntil(stdout_read, "Base.REPL")
    write(stdin_write, '\x03')
    write(stdin_write, "\\alpha\t")
    readuntil(stdout_read,"α")
    write(stdin_write, '\x03')
    # Test cd feature in shell mode.  We limit to 40 characters when
    # calling readuntil() to suppress the warning it (currently) gives for
    # long strings.
    origpwd = pwd()
    mktempdir() do tmpdir
        write(stdin_write, ";")
        readuntil(stdout_read, "shell> ")
        write(stdin_write, "cd $(escape_string(tmpdir))\n")
        readuntil(stdout_read, "cd $(escape_string(tmpdir))"[max(1,end-39):end])
        readuntil(stdout_read, realpath(tmpdir)[max(1,end-39):end])
        readuntil(stdout_read, "\n")
        readuntil(stdout_read, "\n")
        @test pwd() == realpath(tmpdir)
        write(stdin_write, ";")
        readuntil(stdout_read, "shell> ")
        write(stdin_write, "cd -\n")
        readuntil(stdout_read, origpwd[max(1,end-39):end])
        readuntil(stdout_read, "\n")
        readuntil(stdout_read, "\n")
        @test pwd() == origpwd
        write(stdin_write, ";")
        readuntil(stdout_read, "shell> ")
        write(stdin_write, "cd\n")
        readuntil(stdout_read, realpath(homedir())[max(1,end-39):end])
        readuntil(stdout_read, "\n")
        readuntil(stdout_read, "\n")
        @test pwd() == realpath(homedir())
    end
    cd(origpwd)

    # issue #20482
    if !Sys.iswindows()
        write(stdin_write, ";")
        readuntil(stdout_read, "shell> ")
        write(stdin_write, "echo hello >/dev/null\n")
        let s = readuntil(stdout_read, "\n")
            @test contains(s, "shell> ") # make sure we echoed the prompt
            @test contains(s, "echo hello >/dev/null") # make sure we echoed the input
        end
        @test readuntil(stdout_read, "\n") == "\e[0m\n"
    end

    # issue #20771
    let s
        write(stdin_write, ";")
        readuntil(stdout_read, "shell> ")
        write(stdin_write, "'\n") # invalid input
        s = readuntil(stdout_read, "\n")
        @test contains(s, "shell> ") # check for the echo of the prompt
        @test contains(s, "'") # check for the echo of the input
        s = readuntil(stdout_read, "\n\n")
        @test startswith(s, "\e[0mERROR: unterminated single quote\nStacktrace:\n [1] ") ||
              startswith(s, "\e[0m\e[1m\e[91mERROR: \e[39m\e[22m\e[91munterminated single quote\e[39m\nStacktrace:\n [1] ")
    end

    # issues #22176 & #20482
    # TODO: figure out how to test this on Windows
    Sys.iswindows() || let tmp = tempname()
        try
            write(stdin_write, ";")
            readuntil(stdout_read, "shell> ")
            write(stdin_write, "echo \$123 >$tmp\n")
            let s = readuntil(stdout_read, "\n")
                @test contains(s, "shell> ") # make sure we echoed the prompt
                @test contains(s, "echo \$123 >$tmp") # make sure we echoed the input
            end
            @test readuntil(stdout_read, "\n") == "\e[0m\n"
            @test read(tmp, String) == "123\n"
        finally
            rm(tmp, force=true)
        end
    end

    # Issue #7001
    # Test ignoring '\0'
    let
        write(stdin_write, "\0\n")
        s = readuntil(stdout_read, "\n\n")
        @test !contains(s, "invalid character")
    end

    # Test that accepting a REPL result immediately shows up, not
    # just on the next keystroke
    write(stdin_write, "1+1\n") # populate history with a trivial input
    readline(stdout_read)
    write(stdin_write, "\e[A\n")
    t = Timer(10) do t
        isopen(t) || return
        error("Stuck waiting for the repl to write `1+1`")
    end
    # yield make sure this got processed
    readuntil(stdout_read, "1+1")
    close(t)
    readuntil(stdout_read, "\n\n")

    # Issue #10222
    # Test ignoring insert key in standard and prefix search modes
    write(stdin_write, "\e[2h\e[2h\n") # insert (VT100-style)
    @test search(readline(stdout_read), "[2h") == 0:-1
    readline(stdout_read)
    write(stdin_write, "\e[2~\e[2~\n") # insert (VT220-style)
    @test search(readline(stdout_read), "[2~") == 0:-1
    readline(stdout_read)
    write(stdin_write, "1+1\n") # populate history with a trivial input
    readline(stdout_read)
    write(stdin_write, "\e[A\e[2h\n") # up arrow, insert (VT100-style)
    readline(stdout_read)
    readline(stdout_read)
    write(stdin_write, "\e[A\e[2~\n") # up arrow, insert (VT220-style)
    readline(stdout_read)
    readline(stdout_read)

    # Test down arrow to go back to history
    # populate history with a trivial input

    t = Timer(10) do t
        isopen(t) || return
        error("Stuck waiting for history test")
    end
    s1 = "12345678"; s2 = "23456789"
    write(stdin_write, s1, '\n')
    readuntil(stdout_read, s1)
    write(stdin_write, s2, '\n')
    readuntil(stdout_read, s2)
    # Two up arrow, enter, should get back to 1
    write(stdin_write, "\e[A\e[A\n")
    readuntil(stdout_read, s1)
    # Now, down arrow, enter, should get us back to 2
    write(stdin_write, "\e[B\n")
    readuntil(stdout_read, s2)
    close(t)

    # Close REPL ^D
    write(stdin_write, '\x04')
    wait(repltask)
end

function buffercontents(buf::IOBuffer)
    p = position(buf)
    seek(buf,0)
    c = read(buf, String)
    seek(buf,p)
    c
end

function AddCustomMode(repl, prompt)
    # Custom REPL mode tests
    foobar_mode = LineEdit.Prompt(prompt;
        prompt_prefix="\e[38;5;166m",
        prompt_suffix=Base.text_colors[:white],
        on_enter = s->true,
        on_done = line->true)

    main_mode = repl.interface.modes[1]
    push!(repl.interface.modes,foobar_mode)

    hp = main_mode.hist
    hp.mode_mapping[:foobar] = foobar_mode
    foobar_mode.hist = hp

    foobar_keymap = Dict{Any,Any}(
        '<' => function (s,args...)
            if isempty(s)
                if !haskey(s.mode_state,foobar_mode)
                    s.mode_state[foobar_mode] = LineEdit.init_state(repl.t,foobar_mode)
                end
                LineEdit.transition(s,foobar_mode)
            else
                LineEdit.edit_insert(s,'<')
            end
        end
    )

    search_prompt, skeymap = LineEdit.setup_search_keymap(hp)
    mk = REPL.mode_keymap(main_mode)

    b = Dict{Any,Any}[skeymap, mk, LineEdit.history_keymap, LineEdit.default_keymap, LineEdit.escape_defaults]
    foobar_mode.keymap_dict = LineEdit.keymap(b)

    main_mode.keymap_dict = LineEdit.keymap_merge(main_mode.keymap_dict, foobar_keymap)
    foobar_mode, search_prompt
end

# Note: since the \t character matters for the REPL file history,
# it is important not to have the """ code reindent this line,
# possibly converting \t to spaces.
fakehistory = """
# time: 2014-06-29 20:44:29 EDT
# mode: julia
\té
# time: 2014-06-29 21:44:29 EDT
# mode: julia
\téé
# time: 2014-06-30 17:32:49 EDT
# mode: julia
\tshell
# time: 2014-06-30 17:32:59 EDT
# mode: shell
\tll
# time: 2014-06-30 99:99:99 EDT
# mode: julia
\tx ΔxΔ
# time: 2014-06-30 17:32:49 EDT
# mode: julia
\t1 + 1
# time: 2014-06-30 17:35:39 EDT
# mode: foobar
\tbarfoo
# time: 2014-06-30 18:44:29 EDT
# mode: shell
\tls
# time: 2014-06-30 19:44:29 EDT
# mode: foobar
\tls
# time: 2014-06-30 20:44:29 EDT
# mode: julia
\t2 + 2
"""

# Test various history related issues
for prompt = ["TestΠ", () -> randstring(rand(1:10))]
    fake_repl() do stdin_write, stdout_read, repl
        # In the future if we want we can add a test that the right object
        # gets displayed by intercepting the display
        repl.specialdisplay = Base.REPL.REPLDisplay(repl)

        repl.interface = REPL.setup_interface(repl)
        repl_mode = repl.interface.modes[1]
        shell_mode = repl.interface.modes[2]
        help_mode = repl.interface.modes[3]
        histp = repl.interface.modes[4]
        prefix_mode = repl.interface.modes[5]

        hp = REPL.REPLHistoryProvider(Dict{Symbol,Any}(:julia => repl_mode,
                                                       :shell => shell_mode,
                                                       :help  => help_mode))

        REPL.hist_from_file(hp, IOBuffer(fakehistory), "fakehistorypath")
        REPL.history_reset_state(hp)

        histp.hp = repl_mode.hist = shell_mode.hist = help_mode.hist = hp

        # Some manual setup
        s = LineEdit.init_state(repl.t, repl.interface)
        LineEdit.edit_insert(s, "wip")

        # Test that navigating history skips invalid modes
        # (in both directions)
        LineEdit.history_prev(s, hp)
        @test LineEdit.mode(s) == repl_mode
        @test buffercontents(LineEdit.buffer(s)) == "2 + 2"
        LineEdit.history_prev(s, hp)
        @test LineEdit.mode(s) == shell_mode
        @test buffercontents(LineEdit.buffer(s)) == "ls"
        LineEdit.history_prev(s, hp)
        @test LineEdit.mode(s) == repl_mode
        @test buffercontents(LineEdit.buffer(s)) == "1 + 1"
        LineEdit.history_next(s, hp)
        @test LineEdit.mode(s) == shell_mode
        @test buffercontents(LineEdit.buffer(s)) == "ls"
        LineEdit.history_next(s, hp)
        @test LineEdit.mode(s) == repl_mode
        @test buffercontents(LineEdit.buffer(s)) == "2 + 2"
        LineEdit.history_next(s, hp)
        @test LineEdit.mode(s) == repl_mode
        @test buffercontents(LineEdit.buffer(s)) == "wip"
        @test position(LineEdit.buffer(s)) == 3
        LineEdit.history_next(s, hp)
        @test buffercontents(LineEdit.buffer(s)) == "wip"
        LineEdit.history_prev(s, hp, 2)
        @test LineEdit.mode(s) == shell_mode
        @test buffercontents(LineEdit.buffer(s)) == "ls"
        LineEdit.history_prev(s, hp, -2) # equivalent to history_next(s, hp, 2)
        @test LineEdit.mode(s) == repl_mode
        @test buffercontents(LineEdit.buffer(s)) == "2 + 2"
        LineEdit.history_next(s, hp, -2) # equivalent to history_prev(s, hp, 2)
        @test LineEdit.mode(s) == shell_mode
        @test buffercontents(LineEdit.buffer(s)) == "ls"
        LineEdit.history_first(s, hp)
        @test LineEdit.mode(s) == repl_mode
        @test buffercontents(LineEdit.buffer(s)) == "é"
        LineEdit.history_next(s, hp, 6)
        @test LineEdit.mode(s) == shell_mode
        @test buffercontents(LineEdit.buffer(s)) == "ls"
        LineEdit.history_last(s, hp)
        @test buffercontents(LineEdit.buffer(s)) == "wip"
        @test position(LineEdit.buffer(s)) == 3
        # test that history_first jumps to beginning of current session's history
        hp.start_idx -= 5 # temporarily alter history
        LineEdit.history_first(s, hp)
        @test hp.cur_idx == 6
        # we are at the beginning of current session's history, so history_first
        # must now jump to the beginning of all history
        LineEdit.history_first(s, hp)
        @test hp.cur_idx == 1
        LineEdit.history_last(s, hp)
        @test hp.cur_idx-1 == length(hp.history)
        hp.start_idx += 5
        LineEdit.move_line_start(s)
        @test position(LineEdit.buffer(s)) == 0

        # Test that the same holds for prefix search
        ps = LineEdit.state(s, prefix_mode)::LineEdit.PrefixSearchState
        @test LineEdit.input_string(ps) == ""
        LineEdit.enter_prefix_search(s, prefix_mode, true)
        LineEdit.history_prev_prefix(ps, hp, "")
        @test ps.prefix == ""
        @test ps.parent == repl_mode
        @test LineEdit.input_string(ps) == "2 + 2"
        @test position(LineEdit.buffer(s)) == 5
        LineEdit.history_prev_prefix(ps, hp, "")
        @test ps.parent == shell_mode
        @test LineEdit.input_string(ps) == "ls"
        @test position(LineEdit.buffer(s)) == 2
        LineEdit.history_prev_prefix(ps, hp, "sh")
        @test ps.parent == repl_mode
        @test LineEdit.input_string(ps) == "shell"
        @test position(LineEdit.buffer(s)) == 2
        LineEdit.history_next_prefix(ps, hp, "sh")
        @test ps.parent == repl_mode
        @test LineEdit.input_string(ps) == "wip"
        @test position(LineEdit.buffer(s)) == 0
        LineEdit.move_input_end(s)
        LineEdit.history_prev_prefix(ps, hp, "é")
        @test ps.parent == repl_mode
        @test LineEdit.input_string(ps) == "éé"
        @test position(LineEdit.buffer(s)) == sizeof("é") > 1
        LineEdit.history_prev_prefix(ps, hp, "é")
        @test ps.parent == repl_mode
        @test LineEdit.input_string(ps) == "é"
        @test position(LineEdit.buffer(s)) == sizeof("é")
        LineEdit.history_next_prefix(ps, hp, "zzz")
        @test ps.parent == repl_mode
        @test LineEdit.input_string(ps) == "wip"
        @test position(LineEdit.buffer(s)) == 3
        LineEdit.accept_result(s, prefix_mode)

        # Test that searching backwards puts you into the correct mode and
        # skips invalid modes.
        LineEdit.enter_search(s, histp, true)
        ss = LineEdit.state(s, histp)
        write(ss.query_buffer, "l")
        LineEdit.update_display_buffer(ss, ss)
        LineEdit.accept_result(s, histp)
        @test LineEdit.mode(s) == shell_mode
        @test buffercontents(LineEdit.buffer(s)) == "ls"
        @test position(LineEdit.buffer(s)) == 0

        # Test that searching for `ll` actually matches `ll` after
        # both letters are types rather than jumping to `shell`
        LineEdit.history_prev(s, hp)
        LineEdit.enter_search(s, histp, true)
        write(ss.query_buffer, "l")
        LineEdit.update_display_buffer(ss, ss)
        @test buffercontents(ss.response_buffer) == "ll"
        @test position(ss.response_buffer) == 1
        write(ss.query_buffer, "l")
        LineEdit.update_display_buffer(ss, ss)
        LineEdit.accept_result(s, histp)
        @test LineEdit.mode(s) == shell_mode
        @test buffercontents(LineEdit.buffer(s)) == "ll"
        @test position(LineEdit.buffer(s)) == 0

        # Test that searching backwards with a one-letter query doesn't
        # return indefinitely the same match (#9352)
        LineEdit.enter_search(s, histp, true)
        write(ss.query_buffer, "l")
        LineEdit.update_display_buffer(ss, ss)
        LineEdit.history_next_result(s, ss)
        LineEdit.update_display_buffer(ss, ss)
        LineEdit.accept_result(s, histp)
        @test LineEdit.mode(s) == repl_mode
        @test buffercontents(LineEdit.buffer(s)) == "shell"
        @test position(LineEdit.buffer(s)) == 4

        # Test that searching backwards doesn't skip matches (#9352)
        # (for a search with multiple one-byte characters, or UTF-8 characters)
        LineEdit.enter_search(s, histp, true)
        write(ss.query_buffer, "é") # matches right-most "é" in "éé"
        LineEdit.update_display_buffer(ss, ss)
        @test position(ss.query_buffer) == sizeof("é")
        LineEdit.history_next_result(s, ss) # matches left-most "é" in "éé"
        LineEdit.update_display_buffer(ss, ss)
        LineEdit.accept_result(s, histp)
        @test buffercontents(LineEdit.buffer(s)) == "éé"
        @test position(LineEdit.buffer(s)) == 0

        # Issue #7551
        # Enter search mode and try accepting an empty result
        REPL.history_reset_state(hp)
        LineEdit.edit_clear(s)
        cur_mode = LineEdit.mode(s)
        LineEdit.enter_search(s, histp, true)
        LineEdit.accept_result(s, histp)
        @test LineEdit.mode(s) == cur_mode
        @test buffercontents(LineEdit.buffer(s)) == ""
        @test position(LineEdit.buffer(s)) == 0

        # Test that new modes can be dynamically added to the REPL and will
        # integrate nicely
        foobar_mode, custom_histp = AddCustomMode(repl, prompt)

        # ^R l, should now find `ls` in foobar mode
        LineEdit.enter_search(s, histp, true)
        ss = LineEdit.state(s, histp)
        write(ss.query_buffer, "l")
        LineEdit.update_display_buffer(ss, ss)
        LineEdit.accept_result(s, histp)
        @test LineEdit.mode(s) == foobar_mode
        @test buffercontents(LineEdit.buffer(s)) == "ls"
        @test position(LineEdit.buffer(s)) == 0

        # Try the same for prefix search
        LineEdit.history_next(s, hp)
        LineEdit.history_prev_prefix(ps, hp, "l")
        @test ps.parent == foobar_mode
        @test LineEdit.input_string(ps) == "ls"
        @test position(LineEdit.buffer(s)) == 1

        # Some Unicode handling testing
        LineEdit.history_prev(s, hp)
        LineEdit.enter_search(s, histp, true)
        write(ss.query_buffer, "x")
        LineEdit.update_display_buffer(ss, ss)
        @test buffercontents(ss.response_buffer) == "x ΔxΔ"
        @test position(ss.response_buffer) == 4
        write(ss.query_buffer, " ")
        LineEdit.update_display_buffer(ss, ss)
        LineEdit.accept_result(s, histp)
        @test LineEdit.mode(s) == repl_mode
        @test buffercontents(LineEdit.buffer(s)) == "x ΔxΔ"
        @test position(LineEdit.buffer(s)) == 0

        # Try entering search mode while in custom repl mode
        LineEdit.enter_search(s, custom_histp, true)
    end
end

# Test removal of prompt in bracket pasting
fake_repl() do stdin_write, stdout_read, repl
    repl.interface = REPL.setup_interface(repl)
    repl_mode = repl.interface.modes[1]
    shell_mode = repl.interface.modes[2]
    help_mode = repl.interface.modes[3]

    repltask = @async begin
        Base.REPL.run_repl(repl)
    end

    global c = Condition()
    sendrepl2(cmd) = write(stdin_write, "$cmd\n notify($(curmod_prefix)c)\n")

    # Test removal of prefix in single statement paste
    sendrepl2("\e[200~julia> A = 2\e[201~\n")
    wait(c)
    @test Main.A == 2

    # Test removal of prefix in multiple statement paste
    sendrepl2("""\e[200~
            julia> mutable struct T17599; a::Int; end

            julia> function foo(julia)
            julia> 3
                end

                    julia> A = 3\e[201~
             """)
    wait(c)
    @test Main.A == 3
    @test Base.invokelatest(Main.foo, 4)
    @test Base.invokelatest(Main.T17599, 3).a == 3
    @test !Base.invokelatest(Main.foo, 2)

    sendrepl2("""\e[200~
            julia> goo(x) = x + 1
            error()

            julia> A = 4
            4\e[201~
             """)
    wait(c)
    @test Main.A == 4
    @test Base.invokelatest(Main.goo, 4) == 5

    # Test prefix removal only active in bracket paste mode
    sendrepl2("julia = 4\n julia> 3 && (A = 1)\n")
    wait(c)
    @test Main.A == 1

    # Test that indentation corresponding to the prompt is removed
    sendrepl2("""\e[200~julia> begin\n           α=1\n           β=2\n       end\n\e[201~""")
    wait(c)
    readuntil(stdout_read, "begin")
    @test readuntil(stdout_read, "end") == "\n\r\e[7C    α=1\n\r\e[7C    β=2\n\r\e[7Cend"
    # for incomplete input (`end` below is added after the end of bracket paste)
    sendrepl2("""\e[200~julia> begin\n           α=1\n           β=2\n\e[201~end""")
    wait(c)
    readuntil(stdout_read, "begin")
    readuntil(stdout_read, "begin")
    @test readuntil(stdout_read, "end") == "\n\r\e[7C    α=1\n\r\e[7C    β=2\n\r\e[7Cend"

    # Close repl
    write(stdin_write, '\x04')
    wait(repltask)
end

# Simple non-standard REPL tests
fake_repl() do stdin_write, stdout_read, repl
    panel = LineEdit.Prompt("testπ";
        prompt_prefix="\e[38;5;166m",
        prompt_suffix=Base.text_colors[:white],
        on_enter = s->true)

    hp = REPL.REPLHistoryProvider(Dict{Symbol,Any}(:parse => panel))
    search_prompt, skeymap = LineEdit.setup_prefix_keymap(hp, panel)
    REPL.history_reset_state(hp)

    panel.hist = hp
    panel.keymap_dict = LineEdit.keymap(Dict{Any,Any}[skeymap,
        LineEdit.default_keymap, LineEdit.escape_defaults])

    c = Condition()
    panel.on_done = (s,buf,ok)->begin
        if !ok
            LineEdit.transition(s,:abort)
        end
        line = strip(String(take!(buf)))
        LineEdit.reset_state(s)
        return notify(c,line)
    end

    repltask = @async Base.REPL.run_interface(repl.t, LineEdit.ModalInterface([panel,search_prompt]))

    write(stdin_write,"a\n")
    @test wait(c) == "a"
    # Up arrow enter should recall history even at the start
    write(stdin_write,"\e[A\n")
    @test wait(c) == "a"
    # And again
    write(stdin_write,"\e[A\n")
    @test wait(c) == "a"
    # Close REPL ^D
    write(stdin_write, '\x04')
    wait(repltask)
end

ccall(:jl_exit_on_sigint, Void, (Cint,), 1)

let exename = Base.julia_cmd()
    # Test REPL in dumb mode
    if !Sys.iswindows()
        TestHelpers.with_fake_pty() do slave, master
            nENV = copy(ENV)
            nENV["TERM"] = "dumb"
            p = spawn(setenv(`$exename --startup-file=no -q`,nENV),slave,slave,slave)
            output = readuntil(master,"julia> ")
            if ccall(:jl_running_on_valgrind,Cint,()) == 0
                # If --trace-children=yes is passed to valgrind, we will get a
                # valgrind banner here, not just the prompt.
                @test output == "julia> "
            end
            write(master,"1\nquit()\n")

            wait(p)
            output = readuntil(master,' ')
            @test output == "1\r\nquit()\r\n1\r\n\r\njulia> "
            @test nb_available(master) == 0
        end
    end

    # Test stream mode
    outs, ins, p = readandwrite(`$exename --startup-file=no -q`)
    write(ins,"1\nquit()\n")
    @test read(outs, String) == "1\n"
end # let exename

# issue #19864:
mutable struct Error19864 <: Exception; end
function test19864()
    @eval Base.showerror(io::IO, e::Error19864) = print(io, "correct19864")
    buf = IOBuffer()
    REPL.print_response(buf, Error19864(), [], false, false, nothing)
    return String(take!(buf))
end
@test contains(test19864(), "correct19864")

# Test containers in error messages are limited #18726
let io = IOBuffer()
    Base.display_error(io,
        try
            [][trues(6000)]
        catch e
            e
        end, [])
    @test length(String(take!(io))) < 1500
end

fake_repl() do stdin_write, stdout_read, repl
    # Relies on implementation detail to make sure we only have the single
    # replinit callback we want to test.
    saved_replinit = copy(Base.repl_hooks)
    slot = Ref(false)
    # Create a closure from a newer world to check if `_atreplinit`
    # can run it correctly
    atreplinit(@eval(repl::Base.REPL.LineEditREPL -> ($slot[] = true)))
    Base._atreplinit(repl)
    @test slot[]
    @test_throws MethodError Base.repl_hooks[1](repl)
    copy!(Base.repl_hooks, saved_replinit)
    nothing
end

let ends_with_semicolon = Base.REPL.ends_with_semicolon
    @test !ends_with_semicolon("")
    @test ends_with_semicolon(";")
    @test !ends_with_semicolon("a")
    @test ends_with_semicolon("1;")
    @test ends_with_semicolon("1;\n")
    @test ends_with_semicolon("1;\r")
    @test ends_with_semicolon("1;\r\n   \t\f")
    @test ends_with_semicolon("1;#text\n")
    @test ends_with_semicolon("a; #=#=# =# =#\n")
    @test !ends_with_semicolon("begin\na;\nb;\nend")
    @test !ends_with_semicolon("begin\na; #=#=#\n=#b=#\nend")
    @test ends_with_semicolon("\na; #=#=#\n=#b=#\n# test\n#=\nfoobar\n=##bazbax\n")
end

# PR #20794, TTYTerminal with other kinds of streams
let term = Base.Terminals.TTYTerminal("dumb",IOBuffer("1+2\n"),IOBuffer(),IOBuffer())
    r = Base.REPL.BasicREPL(term)
    REPL.run_repl(r)
    @test String(take!(term.out_stream)) == "julia> 3\n\njulia> \n"
end


# a small module for alternative keymap tests
module AltLE
import Base: LineEdit, REPL

function history_move_prefix(s::LineEdit.MIState,
                             hist::REPL.REPLHistoryProvider,
                             backwards::Bool)
    buf = LineEdit.buffer(s)
    pos = position(buf)
    prefix = REPL.beforecursor(buf)
    allbuf = String(take!(copy(buf)))
    cur_idx = hist.cur_idx
    # when searching forward, start at last_idx
    if !backwards && hist.last_idx > 0
        cur_idx = hist.last_idx
    end
    hist.last_idx = -1
    idxs = backwards ? ((cur_idx-1):-1:1) : ((cur_idx+1):length(hist.history))
    for idx in idxs
        if startswith(hist.history[idx], prefix) && hist.history[idx] != allbuf
            REPL.history_move(s, hist, idx)
            seek(LineEdit.buffer(s), pos)
            LineEdit.refresh_line(s)
            return :ok
        end
    end
    REPL.Terminals.beep(LineEdit.terminal(s))
end
history_next_prefix(s::LineEdit.MIState, hist::REPL.REPLHistoryProvider) =
    history_move_prefix(s, hist, false)
history_prev_prefix(s::LineEdit.MIState, hist::REPL.REPLHistoryProvider) =
    history_move_prefix(s, hist, true)

end # module

# Test alternative keymaps and prompt
# (Alt. keymaps may be passed as a Vector{<:Dict} or as a Dict)

const altkeys = [Dict{Any,Any}("\e[A" => (s,o...)->(LineEdit.edit_move_up(s) || LineEdit.history_prev(s, LineEdit.mode(s).hist))), # Up Arrow
                 Dict{Any,Any}("\e[B" => (s,o...)->(LineEdit.edit_move_down(s) || LineEdit.history_next(s, LineEdit.mode(s).hist))), # Down Arrow
                 Dict{Any,Any}("\e[5~" => (s,o...)->(AltLE.history_prev_prefix(s, LineEdit.mode(s).hist))), # Page Up
                 Dict{Any,Any}("\e[6~" => (s,o...)->(AltLE.history_next_prefix(s, LineEdit.mode(s).hist))), # Page Down
                ]


for keys = [altkeys, merge(altkeys...)],
        altprompt = ["julia-$(VERSION.major).$(VERSION.minor)> ",
                     () -> "julia-$(Base.GIT_VERSION_INFO.commit_short)"]
    histfile = tempname()
    try
        fake_repl() do stdin_write, stdout_read, repl
            repl.specialdisplay = Base.REPL.REPLDisplay(repl)
            repl.history_file = true
            withenv("JULIA_HISTORY" => histfile) do
                repl.interface = REPL.setup_interface(repl, extra_repl_keymap = altkeys)
            end
            repl.interface.modes[1].prompt = altprompt

            repltask = @async begin
                Base.REPL.run_repl(repl)
            end

            sendrepl3(cmd) = write(stdin_write,"$cmd\n")

            sendrepl3("1 + 1;")                        # a simple line
            sendrepl3("multi=2;\e\nline=2;")           # a multiline input
            sendrepl3("ignoreme\e[A\b\b3;\e[B\b\b1;")  # edit the previous multiline input
            sendrepl3("1 +\e[5~\b*")                   # use prefix search to edit the 1st input

            # Close REPL ^D
            write(stdin_write, '\x04')
            wait(repltask)

            # Close the history file
            # (otherwise trying to delete it fails on Windows)
            close(repl.interface.modes[1].hist.history_file)

            # Check that the correct prompt was displayed
            output = readuntil(stdout_read, "1 * 1;")
            @test !isempty(search(output, LineEdit.prompt_string(altprompt)))
            @test isempty(search(output, "julia> "))

            # Check the history file
            history = read(histfile, String)
            @test ismatch(r"""
                          ^\#\ time:\ .*\n
                           \#\ mode:\ julia\n
                           \t1\ \+\ 1;\n
                           \#\ time:\ .*\n
                           \#\ mode:\ julia\n
                           \tmulti=2;\n
                           \tline=2;\n
                           \#\ time:\ .*\n
                           \#\ mode:\ julia\n
                           \tmulti=3;\n
                           \tline=1;\n
                           \#\ time:\ .*\n
                           \#\ mode:\ julia\n
                           \t1\ \*\ 1;\n$
                          """xm, history)
        end
    finally
        rm(histfile, force=true)
    end
end