fix: preserve trailing newlines and silence empty output

- Accumulate raw bytes in executeRaw instead of stripping \r\n per line,
  so println output retains its trailing newline while print does not
- Remove "(no output)" placeholder; suppress blank line for empty output
- Switch -e/--eval flags and --project (replaces --env) to mirror julia CLI
- Add proc_windows.go stub so Windows builds succeed

Author: Beforerr

go/client_test.go

@@ -225,26 +225,36 @@ func TestEvalBasic(t *testing.T) {
 		t.Fatalf("eval error: %v", resp["error"])
 	}
 	out, _ := resp["output"].(string)
-	if out != "hello world" {
-		t.Errorf("eval output = %q, want %q", out, "hello world")
+	if out != "hello world\n" {
+		t.Errorf("eval output = %q, want %q", out, "hello world\n")
 	}
 
 	// State persists across calls
 	send(map[string]any{"action": "eval", "code": "x = 42"})
 	resp2 := send(map[string]any{"action": "eval", "code": "println(x)"})
 	out2, _ := resp2["output"].(string)
-	if out2 != "42" {
-		t.Errorf("state not persisted: x = %q, want 42", out2)
+	if out2 != "42\n" {
+		t.Errorf("state not persisted: x = %q, want %q", out2, "42\n")
 	}
 
 	// Restart clears state
 	send(map[string]any{"action": "restart"})
 	resp3 := send(map[string]any{"action": "eval", "code": "println(isdefined(Main, :x))"})
 	out3, _ := resp3["output"].(string)
-	if out3 != "false" {
+	if out3 != "false\n" {
 		t.Errorf("after restart x should be undefined, got %q", out3)
 	}
 
+	// println adds trailing newline; print does not
+	resp4 := send(map[string]any{"action": "eval", "code": `print("no-nl")`})
+	if out4, _ := resp4["output"].(string); out4 != "no-nl" {
+		t.Errorf("print output = %q, want %q", out4, "no-nl")
+	}
+	resp5 := send(map[string]any{"action": "eval", "code": `println("with-nl")`})
+	if out5, _ := resp5["output"].(string); out5 != "with-nl\n" {
+		t.Errorf("println output = %q, want %q", out5, "with-nl\n")
+	}
+
 	// Stop daemon
 	conn, _ := net.Dial("unix", socketPath)
 	json.NewEncoder(conn).Encode(map[string]any{"action": "stop"})

go/daemon.go

@@ -60,9 +60,6 @@ func handleRequest(state *daemonState, req map[string]any) map[string]any {
 			}
 			return errResp(err.Error())
 		}
-		if output == "" {
-			output = "(no output)"
-		}
 		return map[string]any{"output": output, "error": nil}
 
 	case "restart":

go/main.go

@@ -118,7 +118,9 @@ func run(socketPath string, payload map[string]any, startIfNeeded bool) {
 		fmt.Fprintln(os.Stderr, resp.Error)
 		os.Exit(1)
 	}
-	fmt.Println(resp.Output)
+	if resp.Output != "" {
+		fmt.Print(resp.Output)
+	}
 }
 
 func cmdEval(socketPath, code, project string, timeout float64, juliaCmd string) {

go/session.go

@@ -139,11 +139,14 @@ func (s *JuliaSession) isAlive() bool {
 }
 
 type readResult struct {
-	lines []string
-	err   error
+	output string
+	err    error
 }
 
 func (s *JuliaSession) executeRaw(code string, timeoutSecs float64) (string, error) {
+	// The sentinel command writes an extra "\n" before the marker so it always
+	// starts on its own line even when the user code didn't end with a newline.
+	// We strip exactly that one "\n" when assembling the result.
 	sentinelCmd := fmt.Sprintf(
 		"flush(stderr); write(stdout, \"\\n\"); println(stdout, \"%s\"); flush(stdout)\n",
 		s.sentinel,
@@ -154,46 +157,46 @@ func (s *JuliaSession) executeRaw(code string, timeoutSecs float64) (string, err
 
 	ch := make(chan readResult, 1)
 	go func() {
-		var lines []string
+		var buf strings.Builder
 		for {
 			line, err := s.stdout.ReadString('\n')
-			trimmed := strings.TrimRight(line, "\r\n")
-			if trimmed == s.sentinel {
-				if len(lines) > 0 && lines[len(lines)-1] == "" {
-					lines = lines[:len(lines)-1]
+			if strings.TrimRight(line, "\r\n") == s.sentinel {
+				// Strip the one "\n" we injected before the sentinel.
+				out := buf.String()
+				if len(out) > 0 && out[len(out)-1] == '\n' {
+					out = out[:len(out)-1]
 				}
-				ch <- readResult{lines, nil}
+				ch <- readResult{out, nil}
 				return
 			}
 			if err != nil {
 				s.dead.Store(true)
-				ch <- readResult{lines, fmt.Errorf("Julia process died during execution.\nOutput before death:\n%s", strings.Join(lines, "\n"))}
+				ch <- readResult{buf.String(), fmt.Errorf("Julia process died during execution.\nOutput before death:\n%s", buf.String())}
 				return
 			}
-			lines = append(lines, trimmed)
+			buf.WriteString(line)
 		}
 	}()
 
 	if timeoutSecs <= 0 {
 		r := <-ch
-		return strings.Join(r.lines, "\n"), r.err
+		return r.output, r.err
 	}
 
 	timer := time.NewTimer(time.Duration(float64(time.Second) * timeoutSecs))
 	defer timer.Stop()
 
 	select {
 	case r := <-ch:
-		return strings.Join(r.lines, "\n"), r.err
+		return r.output, r.err
 	case <-timer.C:
 		s.proc.Process.Kill()
 		s.proc.Wait()
 		s.dead.Store(true)
 		r := <-ch // goroutine unblocks on EOF after kill
-		partial := strings.Join(r.lines, "\n")
 		msg := fmt.Sprintf("Execution timed out after %vs. Session killed; it will restart on next call.", timeoutSecs)
-		if partial != "" {
-			msg += "\n\nOutput before timeout:\n" + partial
+		if r.output != "" {
+			msg += "\n\nOutput before timeout:\n" + r.output
 		}
 		return "", fmt.Errorf("%s", msg)
 	}

justfile

@@ -1,4 +1,5 @@
 install:
+    julia-client stop
     go build -o ~/.local/bin/julia-client ./go/
     npx skills add . -g -y