feat: expose True() and False() constructors

jsonschema/schema.go

@@ -132,6 +132,14 @@ func falseSchema() *Schema {
 	return &Schema{Not: &Schema{}}
 }
 
+// True returns a Schema that validates any JSON value.
+// It is equivalent to the empty schema ({}), which marshals to the JSON literal true.
+func True() *Schema { return &Schema{} }
+
+// False returns a Schema that validates no JSON value.
+// It is equivalent to the schema {"not": {}}, which marshals to the JSON literal false.
+func False() *Schema { return falseSchema() }
+
 // anchorInfo records the subschema to which an anchor refers, and whether
 // the anchor keyword is $anchor or $dynamicAnchor.
 type anchorInfo struct {

jsonschema/schema_true_false_test.go

@@ -0,0 +1,50 @@
+package jsonschema
+
+import (
+    "encoding/json"
+    "testing"
+)
+
+func TestTrueFalseConstructors_Marshal(t *testing.T) {
+    bt, err := json.Marshal(True())
+    if err != nil {
+        t.Fatalf("Marshal(True()) error: %v", err)
+    }
+    if string(bt) != "true" {
+        t.Fatalf("Marshal(True()) = %s, want true", string(bt))
+    }
+
+    bf, err := json.Marshal(False())
+    if err != nil {
+        t.Fatalf("Marshal(False()) error: %v", err)
+    }
+    if string(bf) != "false" {
+        t.Fatalf("Marshal(False()) = %s, want false", string(bf))
+    }
+}
+
+func TestTrueFalseConstructors_Validate(t *testing.T) {
+    rsTrue, err := True().Resolve(nil)
+    if err != nil {
+        t.Fatalf("True().Resolve() error: %v", err)
+    }
+    // Should validate any instance
+    cases := []any{nil, true, false, 0, 3.14, "x", map[string]any{"a": 1}, []any{1, 2}}
+    for i, c := range cases {
+        if err := rsTrue.Validate(c); err != nil {
+            t.Fatalf("True().Validate case %d failed: %v", i, err)
+        }
+    }
+
+    rsFalse, err := False().Resolve(nil)
+    if err != nil {
+        t.Fatalf("False().Resolve() error: %v", err)
+    }
+    // Should reject any instance
+    for i, c := range cases {
+        if err := rsFalse.Validate(c); err == nil {
+            t.Fatalf("False().Validate case %d succeeded unexpectedly", i)
+        }
+    }
+}
+