1 files changed, 76 insertions, 0 deletions
diff --git a/gui/internal/model/testrule_test.go b/gui/internal/model/testrule_test.go
new file mode 100644
index 0000000..99989f4
--- /dev/null
+++ b/gui/internal/model/testrule_test.go
@@ -0,0 +1,76 @@
+// SPDX-License-Identifier: GPL-3.0-or-later
+
+package model
+
+import (
+	"context"
+	"strings"
+	"testing"
+)
+
+// TestTestRule: testing one rule says which of the directory's files it
+// would act on, and what would happen to each - answered from the unsaved
+// text, and changing nothing (GUI design §5.3, his request 2026-09-16).
+func TestTestRule(t *testing.T) {
+	conf := "(path \"~/dl\")\n" +
+		"(rule \"pdfs\" (when (type pdf)) (move \"Docs\") (stop))\n" +
+		"(rule \"rest\" (move \"Other\"))\n"
+	e, _ := sandboxDir(t, conf, map[string]string{
+		"a.pdf": "one", "b.pdf": "two", "c.txt": "three",
+	})
+	r, err := OpenRules(e, "dl")
+	if err != nil {
+		t.Fatal(err)
+	}
+
+	hits, err := r.TestRule(context.Background(), "pdfs")
+	if err != nil {
+		t.Fatal(err)
+	}
+	if hits.Scanned != 3 || len(hits.Files) != 2 {
+		t.Fatalf("hits = %+v", hits)
+	}
+	for _, h := range hits.Files {
+		if !strings.HasSuffix(h.Rel, ".pdf") {
+			t.Errorf("a file the rule does not match: %+v", h)
+		}
+		if len(h.Steps) == 0 || !strings.Contains(h.Steps[0].Dst, "Docs") {
+			t.Errorf("%s: steps = %+v", h.Rel, h.Steps)
+		}
+	}
+
+	// The unsaved text is what is tested, not what is on disk.
+	r.SetText("(path \"~/dl\")\n(rule \"pdfs\" (when (type text)) (move \"Docs\") (stop))\n")
+	hits, err = r.TestRule(context.Background(), "pdfs")
+	if err != nil {
+		t.Fatal(err)
+	}
+	if len(hits.Files) != 1 || hits.Files[0].Rel != "c.txt" {
+		t.Errorf("the unsaved rule was not the one tested: %+v", hits)
+	}
+
+	// A rule that matches nothing says so rather than failing.
+	r.SetText("(path \"~/dl\")\n(rule \"pdfs\" (when (type iso)) (move \"Docs\") (stop))\n")
+	hits, err = r.TestRule(context.Background(), "pdfs")
+	if err != nil || len(hits.Files) != 0 || hits.Scanned != 3 {
+		t.Errorf("hits = %+v, err = %v", hits, err)
+	}
+}
+
+// TestTestRuleRefusals: a rule that is not in the text, and text that does
+// not load, are reported rather than answered.
+func TestTestRuleRefusals(t *testing.T) {
+	conf := "(path \"~/dl\")\n(rule \"pdfs\" (when (type pdf)) (move \"Docs\"))\n"
+	e, _ := sandboxDir(t, conf, map[string]string{"a.pdf": "one"})
+	r, err := OpenRules(e, "dl")
+	if err != nil {
+		t.Fatal(err)
+	}
+	if _, err := r.TestRule(context.Background(), "nosuch"); err == nil {
+		t.Error("a rule that is not in the file was tested")
+	}
+	r.SetText("(path \"~/dl\")\n(rule \"pdfs\" (when (type pdf)) (move \"Docs/{nope}\"))\n")
+	if _, err := r.TestRule(context.Background(), "pdfs"); err == nil {
+		t.Error("text that does not load was tested")
+	}
+}