feat(REPL): Make shell command handling extensible via dispatch; add Nushell

base/client.jl

@@ -31,7 +31,38 @@ answer_color() = text_colors[repl_color("JULIA_ANSWER_COLOR", default_color_answ
 stackframe_lineinfo_color() = repl_color("JULIA_STACKFRAME_LINEINFO_COLOR", :bold)
 stackframe_function_color() = repl_color("JULIA_STACKFRAME_FUNCTION_COLOR", :bold)
 
-function repl_cmd(cmd, out)
+"""
+    ShellSpecification{is_windows, shell}
+
+A type used for dispatch to select the appropriate shell command preparation logic.
+It is parameterized by `is_windows::Bool` indicating the operating system,
+and `shell::Symbol` representing the basename of the shell executable.
+"""
+struct ShellSpecification{is_windows,shell} end
+
+"""
+    prepare_shell_command(spec::ShellSpecification, cmd::Cmd, raw_string::String) -> Cmd
+
+Returns a `Cmd` object configured for execution according to `spec`,
+using the provided `cmd` (parsed command) and `raw_string` (original input).
+Specialized methods for `ShellSpecification` define shell- and OS-specific behavior.
+"""
+function prepare_shell_command(::ShellSpecification{true,shell}, cmd, _) where {shell}
+    return cmd
+end
+function prepare_shell_command(::ShellSpecification{false,shell}, cmd, _) where {shell}
+    shell_escape_cmd = "$(shell_escape_posixly(cmd)) && true"
+    return `$shell -c $shell_escape_cmd`
+end
+function prepare_shell_command(::ShellSpecification{false,:fish}, cmd, _)
+    shell_escape_cmd = "begin; $(shell_escape_posixly(cmd)); and true; end"
+    return `fish -c $shell_escape_cmd`
+end
+function prepare_shell_command(::ShellSpecification{false,:nu}, _, raw_string)
+    return `nu -c $raw_string`
+end
+
+function repl_cmd(cmd, raw_string, out)
     shell = shell_split(get(ENV, "JULIA_SHELL", get(ENV, "SHELL", "/bin/sh")))
     shell_name = Base.basename(shell[1])
 
@@ -64,16 +95,10 @@ function repl_cmd(cmd, out)
         cd(dir)
         println(out, pwd())
     else
-        @static if !Sys.iswindows()
-            if shell_name == "fish"
-                shell_escape_cmd = "begin; $(shell_escape_posixly(cmd)); and true; end"
-            else
-                shell_escape_cmd = "($(shell_escape_posixly(cmd))) && true"
-            end
-            cmd = `$shell -c $shell_escape_cmd`
-        end
+        shell_spec = ShellSpecification{Sys.iswindows(),Symbol(shell_name)}()
+        prepared_cmd = prepare_shell_command(shell_spec, cmd, raw_string)
         try
-            run(ignorestatus(cmd))
+            run(ignorestatus(prepared_cmd))
         catch
             # Windows doesn't shell out right now (complex issue), so Julia tries to run the program itself
             # Julia throws an exception if it can't find the program, but the stack trace isn't useful
@@ -85,6 +110,9 @@ function repl_cmd(cmd, out)
     nothing
 end
 
+# For backward compatibility
+repl_cmd(cmd, out) = repl_cmd(cmd, string(cmd), out)
+
 # deprecated function--preserved for DocTests.jl
 function ip_matches_func(ip, func::Symbol)
     for fr in StackTraces.lookup(ip)

stdlib/REPL/src/REPL.jl

@@ -1335,6 +1335,7 @@ function setup_interface(
         on_done = respond(repl, julia_prompt) do line
             Expr(:call, :(Base.repl_cmd),
                 :(Base.cmd_gen($(Base.shell_parse(line::String)[1]))),
+                line::String,
                 outstream(repl))
         end,
         sticky = true)

test/file.jl

@@ -1925,15 +1925,15 @@ end
         cd(dir) do
             withenv("OLDPWD" => nothing) do
                 io = IOBuffer()
-                Base.repl_cmd(@cmd("cd"), io)
-                Base.repl_cmd(@cmd("cd -"), io)
+                Base.repl_cmd(@cmd("cd"), "cd", io)
+                Base.repl_cmd(@cmd("cd -"), "cd -", io)
                 @test realpath(pwd()) == realpath(dir)
                 if !Sys.iswindows()
                     # Delete the working directory and check we can cd out of it
                     # Cannot delete the working directory on Windows
                     rm(dir)
                     @test_throws Base._UVError("pwd()", Base.UV_ENOENT) pwd()
-                    Base.repl_cmd(@cmd("cd \\~"), io)
+                    Base.repl_cmd(@cmd("cd \\~"), "cd \\~", io)
                 end
             end
         end