bool: accept "on" as true because of HTML checkboxes

.github/workflows/ci.yaml

@@ -24,5 +24,5 @@ jobs:
           just sysinfo
       - name: Run Go Test
         run: |
-          just init tidy lint test
+          just init tidy lint tests
 

Justfile

@@ -13,9 +13,15 @@ default:
 tidy:
     go mod tidy
 
+# run specific unit test
+[group('build')]
+[no-cd]
+test unit:
+    go test -v -count=1 -race -run {{unit}} 2>/dev/null
+
 # run tests across source tree
 [group('build')]
-test:
+tests:
     go test -v -race -count=1 ./...
 
 # apply go vet command on source tree

forms.go

@@ -251,20 +251,23 @@ func BoolOr(b *bool, alt bool) Parser {
 }
 
 func (p *boolParser) Parse(values []string) error {
+	var b bool
+	var err error
+
 	switch {
 	case len(values) > 1:
 		return ErrMulitpleValues
 	case len(values) == 0 && p.required:
 		return ErrNoValue
 	case len(values) == 0:
 		return nil
-	}
-
-	b, err := strconv.ParseBool(values[0])
-	if err != nil {
-		return err
+	case values[0] == "on":
+		// HTML checkbox uses "on" to indicate checked
+		b = true
+	default:
+		b, err = strconv.ParseBool(values[0])
 	}
 
 	*p.destination = b
-	return nil
+	return err
 }

forms_test.go

@@ -247,6 +247,21 @@ func Test_Parse_float_malformed(t *testing.T) {
 	must.Error(t, err)
 }
 
+func Test_Parse_Bool_checkbox_on(t *testing.T) {
+	t.Parallel()
+
+	data := url.Values{
+		"checkbox": []string{"on"},
+	}
+
+	var cb bool
+	err := ParseValues(data, Schema{
+		"checkbox": Bool(&cb),
+	})
+	must.NoError(t, err)
+	must.True(t, cb)
+}
+
 func Test_Parse_bool_value_missing(t *testing.T) {
 	t.Parallel()