fix(schedule): a project that is gone is not listed, so every path outside the list gets the same refusal

internal/frontend/serve/schedules_test.go

@@ -129,7 +129,7 @@ func TestScheduleRefusalsCarryTheirOwnCodes(t *testing.T) {
 		t.Fatal(err)
 	}
 	if status, raw := postSide(t, base+"/schedules/preview", map[string]any{"everySec": 7200, "workspace": gone, "prompt": "x"}); status != http.StatusBadRequest || !strings.Contains(string(raw), "schedule.workspace_unknown") {
-		t.Errorf("a trusted folder that was deleted = %d %s, want schedule.workspace_unknown (trust is filed under the folder's resolved path)", status, raw)
+		t.Errorf("a trusted folder that was deleted = %d %s, want schedule.workspace_unknown ", status, raw)
 	}
 	resp, err := http.Get(base + "/schedules/result?trigger=sch_x/1")
 	if err != nil {

internal/runtime/scheduler/folders.go

@@ -1,6 +1,7 @@
 package scheduler
 
 import (
+	"os"
 	"path/filepath"
 	"runtime"
 	"strings"
@@ -30,6 +31,11 @@ func Folders(current string) []string {
 		if trust, err := grants.Trust(p); err != nil || trust != config.WorkspaceTrusted || contains(out, p) {
 			continue
 		}
+		// A project that is no longer there is not one a schedule can read, and
+		// answering "gone" would tell a caller about paths it was never offered.
+		if info, err := os.Stat(p); err != nil || !info.IsDir() {
+			continue
+		}
 		out = append(out, p)
 	}
 	return out

internal/runtime/scheduler/folders_test.go

@@ -4,6 +4,7 @@ import (
 	"errors"
 	"os"
 	"path/filepath"
+	"slices"
 	"testing"
 
 	"reasonix/internal/contract/config"
@@ -86,3 +87,36 @@ func TestTheTrustedFoldersAreTheRememberedProjectsThePersonTrusted(t *testing.T)
 		t.Fatalf("a project listed and current appears twice: %v", got)
 	}
 }
+
+func TestATrustedProjectThatIsGoneOrIsNotAFolderIsNotListed(t *testing.T) {
+	t.Setenv("REASONIX_HOME", t.TempDir())
+	gone, file := t.TempDir(), filepath.Join(t.TempDir(), "afile")
+	if err := os.WriteFile(file, []byte("x"), 0o644); err != nil {
+		t.Fatal(err)
+	}
+	list := filepath.Join(config.MemoryUserDir(), workspacelist.FileName)
+	if err := workspacelist.Update(t.Context(), list, false, func(l *workspacelist.List) error {
+		l.Paths = append(l.Paths, gone, file)
+		return nil
+	}); err != nil {
+		t.Fatal(err)
+	}
+	grants := config.NewProjectGrantStore(config.RootsForHome("").Home())
+	for _, p := range []string{gone, file} {
+		if err := grants.SetTrust(p, config.WorkspaceTrusted); err != nil {
+			t.Fatal(err)
+		}
+	}
+	if got := Folders(""); !slices.Contains(got, gone) {
+		t.Fatalf("a present trusted project is missing: %v", got)
+	}
+	if got := Folders(""); slices.Contains(got, file) {
+		t.Fatalf("a file was listed as a project: %v", got)
+	}
+	if err := os.RemoveAll(gone); err != nil {
+		t.Fatal(err)
+	}
+	if got := Folders(""); slices.Contains(got, gone) {
+		t.Fatalf("a deleted project is still listed: %v", got)
+	}
+}