REPL: fix hinting without expanding user (#54311)

Fixes #53884

Hints will show without expanding `~`, then a tab will complete the
shown hint, then a second tab on the resulting valid path expands `~`. I
think it makes sense?

https://github.com/JuliaLang/julia/assets/1694067/05a4fa97-2a85-4f90-8591-162256cf0704
(cherry picked from commit 1221160)

Author: IanButterworth

stdlib/REPL/src/LineEdit.jl

@@ -180,11 +180,11 @@ struct EmptyHistoryProvider <: HistoryProvider end
 
 reset_state(::EmptyHistoryProvider) = nothing
 
-complete_line(c::EmptyCompletionProvider, s) = String[], "", true
+complete_line(c::EmptyCompletionProvider, s; hint::Bool=false) = String[], "", true
 
 # complete_line can be specialized for only two arguments, when the active module
 # doesn't matter (e.g. Pkg does this)
-complete_line(c::CompletionProvider, s, ::Module) = complete_line(c, s)
+complete_line(c::CompletionProvider, s, ::Module; hint::Bool=false) = complete_line(c, s; hint)
 
 terminal(s::IO) = s
 terminal(s::PromptState) = s.terminal
@@ -381,7 +381,7 @@ function check_for_hint(s::MIState)
         # Requires making space for them earlier in refresh_multi_line
         return clear_hint(st)
     end
-    completions, partial, should_complete = complete_line(st.p.complete, st, s.active_module)::Tuple{Vector{String},String,Bool}
+    completions, partial, should_complete = complete_line(st.p.complete, st, s.active_module; hint = true)::Tuple{Vector{String},String,Bool}
     isempty(completions) && return clear_hint(st)
     # Don't complete for single chars, given e.g. `x` completes to `xor`
     if length(partial) > 1 && should_complete
@@ -417,8 +417,8 @@ function clear_hint(s::ModeState)
     end
 end
 
-function complete_line(s::PromptState, repeats::Int, mod::Module)
-    completions, partial, should_complete = complete_line(s.p.complete, s, mod)::Tuple{Vector{String},String,Bool}
+function complete_line(s::PromptState, repeats::Int, mod::Module; hint::Bool=false)
+    completions, partial, should_complete = complete_line(s.p.complete, s, mod; hint)::Tuple{Vector{String},String,Bool}
     isempty(completions) && return false
     if !should_complete
         # should_complete is false for cases where we only want to show
@@ -2150,8 +2150,8 @@ setmodifiers!(p::Prompt, m::Modifiers) = setmodifiers!(p.complete, m)
 setmodifiers!(c) = nothing
 
 # Search Mode completions
-function complete_line(s::SearchState, repeats, mod::Module)
-    completions, partial, should_complete = complete_line(s.histprompt.complete, s, mod)
+function complete_line(s::SearchState, repeats, mod::Module; hint::Bool=false)
+    completions, partial, should_complete = complete_line(s.histprompt.complete, s, mod; hint)
     # For now only allow exact completions in search mode
     if length(completions) == 1
         prev_pos = position(s)

stdlib/REPL/src/REPL.jl

@@ -610,26 +610,26 @@ end
 
 beforecursor(buf::IOBuffer) = String(buf.data[1:buf.ptr-1])
 
-function complete_line(c::REPLCompletionProvider, s::PromptState, mod::Module)
+function complete_line(c::REPLCompletionProvider, s::PromptState, mod::Module; hint::Bool=false)
     partial = beforecursor(s.input_buffer)
     full = LineEdit.input_string(s)
-    ret, range, should_complete = completions(full, lastindex(partial), mod, c.modifiers.shift)
+    ret, range, should_complete = completions(full, lastindex(partial), mod, c.modifiers.shift, hint)
     c.modifiers = LineEdit.Modifiers()
     return unique!(map(completion_text, ret)), partial[range], should_complete
 end
 
-function complete_line(c::ShellCompletionProvider, s::PromptState)
+function complete_line(c::ShellCompletionProvider, s::PromptState; hint::Bool=false)
     # First parse everything up to the current position
     partial = beforecursor(s.input_buffer)
     full = LineEdit.input_string(s)
-    ret, range, should_complete = shell_completions(full, lastindex(partial))
+    ret, range, should_complete = shell_completions(full, lastindex(partial), hint)
     return unique!(map(completion_text, ret)), partial[range], should_complete
 end
 
-function complete_line(c::LatexCompletions, s)
+function complete_line(c::LatexCompletions, s; hint::Bool=false)
     partial = beforecursor(LineEdit.buffer(s))
     full = LineEdit.input_string(s)::String
-    ret, range, should_complete = bslash_completions(full, lastindex(partial))[2]
+    ret, range, should_complete = bslash_completions(full, lastindex(partial), hint)[2]
     return unique!(map(completion_text, ret)), partial[range], should_complete
 end
 

stdlib/REPL/src/REPLCompletions.jl

@@ -367,7 +367,8 @@ function complete_path(path::AbstractString;
                        use_envpath=false,
                        shell_escape=false,
                        raw_escape=false,
-                       string_escape=false)
+                       string_escape=false,
+                       contract_user=false)
     @assert !(shell_escape && string_escape)
     if Base.Sys.isunix() && occursin(r"^~(?:/|$)", path)
         # if the path is just "~", don't consider the expanded username as a prefix
@@ -413,15 +414,16 @@ function complete_path(path::AbstractString;
 
     matches = ((shell_escape ? do_shell_escape(s) : string_escape ? do_string_escape(s) : s) for s in matches)
     matches = ((raw_escape ? do_raw_escape(s) : s) for s in matches)
-    matches = Completion[PathCompletion(s) for s in matches]
+    matches = Completion[PathCompletion(contract_user ? contractuser(s) : s) for s in matches]
     return matches, dir, !isempty(matches)
 end
 
 function complete_path(path::AbstractString,
                        pos::Int;
                        use_envpath=false,
                        shell_escape=false,
-                       string_escape=false)
+                       string_escape=false,
+                       contract_user=false)
     ## TODO: enable this depwarn once Pkg is fixed
     #Base.depwarn("complete_path with pos argument is deprecated because the return value [2] is incorrect to use", :complete_path)
     paths, dir, success = complete_path(path; use_envpath, shell_escape, string_escape)
@@ -909,7 +911,7 @@ function close_path_completion(dir, paths, str, pos)
     return lastindex(str) <= pos || str[nextind(str, pos)] != '"'
 end
 
-function bslash_completions(string::String, pos::Int)
+function bslash_completions(string::String, pos::Int, hint::Bool=false)
     slashpos = something(findprev(isequal('\\'), string, pos), 0)
     if (something(findprev(in(bslash_separators), string, pos), 0) < slashpos &&
         !(1 < slashpos && (string[prevind(string, slashpos)]=='\\')))
@@ -1166,7 +1168,7 @@ function complete_identifiers!(suggestions::Vector{Completion}, @nospecialize(ff
     return sort!(unique(suggestions), by=completion_text), (dotpos+1):pos, true
 end
 
-function completions(string::String, pos::Int, context_module::Module=Main, shift::Bool=true)
+function completions(string::String, pos::Int, context_module::Module=Main, shift::Bool=true, hint::Bool=false)
     # First parse everything up to the current position
     partial = string[1:pos]
     inc_tag = Base.incomplete_tag(Meta.parse(partial, raise=false, depwarn=false))
@@ -1219,6 +1221,9 @@ function completions(string::String, pos::Int, context_module::Module=Main, shif
     # its invocation.
     varrange = findprev("var\"", string, pos)
 
+    expanded = nothing
+    was_expanded = false
+
     if varrange !== nothing
         ok, ret = bslash_completions(string, pos)
         ok && return ret
@@ -1235,7 +1240,13 @@ function completions(string::String, pos::Int, context_module::Module=Main, shif
             scs::String = string[r]
 
             expanded = complete_expanduser(scs, r)
-            expanded[3] && return expanded  # If user expansion available, return it
+            was_expanded = expanded[3]
+            if was_expanded
+                scs = (only(expanded[1])::PathCompletion).path
+                # If tab press, ispath and user expansion available, return it now
+                # otherwise see if we can complete the path further before returning with expanded ~
+                !hint && ispath(scs) && return expanded::Completions
+            end
 
             path::String = replace(scs, r"(\\+)\g1(\\?)`" => "\1\2`") # fuzzy unescape_raw_string: match an even number of \ before ` and replace with half as many
             # This expansion with "\\ "=>' ' replacement and shell_escape=true
@@ -1253,12 +1264,19 @@ function completions(string::String, pos::Int, context_module::Module=Main, shif
                         r = nextind(string, startpos + sizeof(dir)):pos
                     else
                         map!(paths, paths) do c::PathCompletion
-                            return PathCompletion(dir * "/" * c.path)
+                            p = dir * "/" * c.path
+                            was_expanded && (p = contractuser(p))
+                            return PathCompletion(p)
                         end
                     end
                 end
             end
-            return sort!(paths, by=p->p.path), r, success
+            if isempty(paths) && !hint && was_expanded
+                # if not able to provide completions, not hinting, and ~ expansion was possible, return ~ expansion
+                return expanded::Completions
+            else
+                return sort!(paths, by=p->p.path), r::UnitRange{Int}, success
+            end
         end
     elseif inc_tag === :string
         # Find first non-escaped quote
@@ -1268,7 +1286,13 @@ function completions(string::String, pos::Int, context_module::Module=Main, shif
             scs::String = string[r]
 
             expanded = complete_expanduser(scs, r)
-            expanded[3] && return expanded  # If user expansion available, return it
+            was_expanded = expanded[3]
+            if was_expanded
+                scs = (only(expanded[1])::PathCompletion).path
+                # If tab press, ispath and user expansion available, return it now
+                # otherwise see if we can complete the path further before returning with expanded ~
+                !hint && ispath(scs) && return expanded::Completions
+            end
 
             path = try
                 unescape_string(replace(scs, "\\\$"=>"\$"))
@@ -1280,7 +1304,9 @@ function completions(string::String, pos::Int, context_module::Module=Main, shif
                 paths, dir, success = complete_path(path::String, string_escape=true)
 
                 if close_path_completion(dir, paths, path, pos)
-                    paths[1] = PathCompletion((paths[1]::PathCompletion).path * "\"")
+                    p = (paths[1]::PathCompletion).path * "\""
+                    hint && was_expanded && (p = contractuser(p))
+                    paths[1] = PathCompletion(p)
                 end
 
                 if success && !isempty(dir)
@@ -1289,21 +1315,31 @@ function completions(string::String, pos::Int, context_module::Module=Main, shif
                         # otherwise make it the whole completion
                         if endswith(dir, "/") && startswith(scs, dir)
                             r = (startpos + sizeof(dir)):pos
-                        elseif startswith(scs, dir * "/")
+                        elseif startswith(scs, dir * "/") && dir != dirname(homedir())
+                            was_expanded && (dir = contractuser(dir))
                             r = nextind(string, startpos + sizeof(dir)):pos
                         else
                             map!(paths, paths) do c::PathCompletion
-                                return PathCompletion(dir * "/" * c.path)
+                                p = dir * "/" * c.path
+                                hint && was_expanded && (p = contractuser(p))
+                                return PathCompletion(p)
                             end
                         end
                     end
                 end
 
                 # Fallthrough allowed so that Latex symbols can be completed in strings
-                success && return sort!(paths, by=p->p.path), r, success
+                if success
+                    return sort!(paths, by=p->p.path), r::UnitRange{Int}, success
+                elseif !hint && was_expanded
+                    # if not able to provide completions, not hinting, and ~ expansion was possible, return ~ expansion
+                    return expanded::Completions
+                end
             end
         end
     end
+    # if path has ~ and we didn't find any paths to complete just return the expanded path
+    was_expanded && return expanded::Completions
 
     ok, ret = bslash_completions(string, pos)
     ok && return ret
@@ -1389,7 +1425,7 @@ end
 module_filter(mod::Module, x::Symbol) =
     Base.isbindingresolved(mod, x) && isdefined(mod, x) && isa(getglobal(mod, x), Module)
 
-function shell_completions(string, pos)
+function shell_completions(string, pos, hint::Bool=false)
     # First parse everything up to the current position
     scs = string[1:pos]
     args, last_arg_start = try
@@ -1407,7 +1443,7 @@ function shell_completions(string, pos)
     # If the last char was a space, but shell_parse ignored it search on "".
     if isexpr(lastarg, :incomplete) || isexpr(lastarg, :error)
         partial = string[last_arg_start:pos]
-        ret, range = completions(partial, lastindex(partial))
+        ret, range = completions(partial, lastindex(partial), Main, true, hint)
         range = range .+ (last_arg_start - 1)
         return ret, range, true
     elseif endswith(scs, ' ') && !endswith(scs, "\\ ")
@@ -1422,9 +1458,16 @@ function shell_completions(string, pos)
         # Also try looking into the env path if the user wants to complete the first argument
         use_envpath = length(args.args) < 2
 
-        # TODO: call complete_expanduser here?
+        expanded = complete_expanduser(path, r)
+        was_expanded = expanded[3]
+        if was_expanded
+            path = (only(expanded[1])::PathCompletion).path
+            # If tab press, ispath and user expansion available, return it now
+            # otherwise see if we can complete the path further before returning with expanded ~
+            !hint && ispath(path) && return expanded::Completions
+        end
 
-        paths, dir, success = complete_path(path, use_envpath=use_envpath, shell_escape=true)
+        paths, dir, success = complete_path(path, use_envpath=use_envpath, shell_escape=true, contract_user=was_expanded)
 
         if success && !isempty(dir)
             let dir = do_shell_escape(dir)
@@ -1442,7 +1485,14 @@ function shell_completions(string, pos)
                 end
             end
         end
-
+        # if ~ was expanded earlier and the incomplete string isn't a path
+        # return the path with contracted user to match what the hint shows. Otherwise expand ~
+        # i.e. require two tab presses to expand user
+        if was_expanded && !ispath(path)
+            map!(paths, paths) do c::PathCompletion
+                PathCompletion(contractuser(c.path))
+            end
+        end
         return paths, r, success
     end
     return Completion[], 0:-1, false