zerowidth_test.gno

 1package vouch
 2
 3import "testing"
 4
 5// Finding 325-input-validation-1 (review run 001-cd0b6a9).
 6//
 7// A validator that calls a field required must agree with the escaper its own
 8// render runs. strings.TrimSpace uses unicode.IsSpace, which does NOT include
 9// U+200B and the rest of the bidi and zero-width set, while every escaper on
10// the output side runs chain/markdown.StripBidiAndZeroWidth, which does. So a
11// value made only of those characters passes validation and renders as
12// nothing: a required field that is blank on the page.
13//
14// The cases below are the invariant, not the implementation. A value the
15// validator accepts must still be non-empty after the stripper.
16func TestValidatorsAgreeWithTheEscaper(t *testing.T) {
17	// One per class the stripper removes, so a fix that handles only
18	// U+200B does not pass.
19	blank := []string{
20		"\u200b\u200b\u200b",   // ZWSP
21		"\u200d",                // ZWJ
22		"\u200e",                // LRM
23		"\u202e",                // RLO
24		"\u2066\u2069",          // LRI PDI
25		"\ufeff",                // BOM
26		" \u200b \u200b ",        // mixed with real spaces
27	}
28	// These must stay valid: the stripper removes the marks and leaves text.
29	ok := []string{
30		"a",
31		"a\u200bb",
32		"  padded  ",
33	}
34
35	for _, s := range blank {
36		if ValidReason(s) {
37			t.Errorf("ValidReason(%q) is true, but the render strips it to empty", s)
38		}
39	}
40	for _, s := range ok {
41		if !ValidReason(s) {
42			t.Errorf("ValidReason(%q) is false, but it renders as real text", s)
43		}
44	}
45
46}