Fix completion at the end of a complete line

ext/REPLExt/REPLExt.jl

@@ -34,7 +34,19 @@ function LineEdit.complete_line(c::PkgCompletionProvider, s; hint::Bool = false)
     partial = REPL.beforecursor(s.input_buffer)
     full = LineEdit.input_string(s)
     ret, range, should_complete = completions(full, lastindex(partial); hint)
-    return ret, partial[range], should_complete
+    # Convert to new completion interface format
+    named_completions = map(LineEdit.NamedCompletion, ret)
+    # Convert UnitRange to Region (Pair{Int,Int}) to match new completion interface
+    # range represents character positions in full string, convert to 0-based byte positions
+    if isempty(range)
+        region = 0 => 0
+    else
+        # Convert 1-based character positions to 0-based byte positions
+        start_pos = thisind(full, first(range)) - 1
+        end_pos = thisind(full, last(range))
+        region = start_pos => end_pos
+    end
+    return named_completions, region, should_complete
 end
 
 prev_project_file = nothing

test/repl.jl

@@ -837,4 +837,28 @@ end
     end
 end
 
+@testset "Pkg completion - edit_move_right fix (issue #58690)" begin
+    # Test that edit_move_right doesn't crash with Pkg completions
+    # This reproduces the issue where pressing right arrow after typing "add minimap2" would crash
+    temp_pkg_dir() do project_path
+        with_pkg_env(project_path) do
+            # Create a fake terminal and prompt state
+            term = REPL.Terminals.TTYTerminal("xterm", stdin, stdout, stderr)
+            prompt = REPL.LineEdit.Prompt("pkg> ")
+            prompt.complete = REPLExt.PkgCompletionProvider()
+
+            s = REPL.LineEdit.MIState(term, prompt, nothing, [prompt])
+            REPL.LineEdit.mode(s, prompt)
+            ps = REPL.LineEdit.state(s, prompt)
+
+            # Set up the input buffer with the problematic text
+            write(ps.input_buffer, "add minimap2")
+            seek(ps.input_buffer, sizeof("add minimap2"))
+
+            # This should not throw an error (it used to throw FieldError)
+            @test_nowarn REPL.LineEdit.edit_move_right(s)
+        end
+    end
+end
+
 end # module