support REPL modes

src/worker.jl

@@ -396,6 +396,16 @@ function worker_init(f::File)
             line::Integer,
         )
             loc = LineNumberNode(line, Symbol(file))
+
+            # handle REPL modes
+            if code[1] == '?'
+                code = "Core.eval(Main.REPL, Main.REPL.helpmode(\"$(code[2:end])\"))"
+            elseif code[1] == ';'
+                code = "Base.repl_cmd(`$(code[2:end])`, stdout)"
+            elseif code[1] == ']'
+                code = "Pkg.REPLMode.PRINTED_REPL_WARNING[]=true; Pkg.REPLMode.do_cmd(Pkg.REPLMode.MiniREPL(),\"$(code[2:end])\")"
+            end
+
             try
                 ast = _parseall(code, filename = file, lineno = line)
                 @assert Meta.isexpr(ast, :toplevel)

test/examples/repl_modes.qmd

@@ -0,0 +1,19 @@
+---
+title: REPL modes
+---
+
+```{julia}
+;echo OK
+```
+
+```{julia}
+;cmd /c echo OK
+```
+
+```{julia}
+] status
+```
+
+```{julia}
+?Int64
+```

test/testsets/repl_modes.jl

@@ -0,0 +1,39 @@
+include("../utilities/prelude.jl")
+
+test_example(joinpath(@__DIR__, "../examples/repl_modes.qmd")) do json
+
+    cells = json["cells"]
+    @test length(cells) == 8
+
+    if !Sys.iswindows()
+        cell = cells[2]
+        @test cell["outputs"][1]["text"] == "OK\n"
+        @test cell["outputs"][1]["output_type"] == "stream"
+        @test cell["outputs"][1]["name"] == "stdout"
+    else
+        # https://github.com/JuliaLang/julia/issues/23597
+        cell = cells[4]
+        @test contains(cell["outputs"][1]["text"], "OK")
+    end
+
+    cell = cells[6]
+    @test cell["outputs"][1]["output_type"] == "stream"
+    @test cell["outputs"][1]["name"] == "stdout"
+    @test contains(cell["outputs"][1]["text"], "Status")
+    @test contains(cell["outputs"][1]["text"], "Project.toml")
+
+    cell = cells[8]
+    @test cell["outputs"][1]["output_type"] == "stream"
+    @test cell["outputs"][1]["name"] == "stdout"
+    @test contains(cell["outputs"][1]["text"], "search")
+
+    @test cell["outputs"][2]["output_type"] == "execute_result"
+    @test contains(cell["outputs"][2]["data"]["text/plain"], "64-bit signed integer type")
+    @test contains(
+        cell["outputs"][2]["data"]["text/markdown"],
+        "64-bit signed integer type",
+    )
+    @test contains(cell["outputs"][2]["data"]["text/html"], "64-bit signed integer type")
+    @test contains(cell["outputs"][2]["data"]["text/latex"], "64-bit signed integer type")
+
+end