Lint properties set to the empty object

Signed-off-by: Juan Cruz Viotti <jv@jviotti.com>

src/linter/CMakeLists.txt

@@ -33,6 +33,7 @@ noa_library(NAMESPACE sourcemeta PROJECT alterschema NAME linter
     redundant/items_schema_default.h
     redundant/max_contains_without_contains.h
     redundant/min_contains_without_contains.h
+    redundant/properties_default.h
     redundant/then_without_if.h
     redundant/unevaluated_items_default.h
     redundant/unevaluated_properties_default.h)

src/linter/linter.cc

@@ -43,6 +43,7 @@ auto contains_any(const T &container, const T &values) -> bool {
 #include "redundant/items_schema_default.h"
 #include "redundant/max_contains_without_contains.h"
 #include "redundant/min_contains_without_contains.h"
+#include "redundant/properties_default.h"
 #include "redundant/then_without_if.h"
 #include "redundant/unevaluated_items_default.h"
 #include "redundant/unevaluated_properties_default.h"
@@ -84,6 +85,7 @@ auto add(Bundle &bundle, const LinterCategory category) -> void {
       bundle.add<ItemsSchemaDefault>();
       bundle.add<MaxContainsWithoutContains>();
       bundle.add<MinContainsWithoutContains>();
+      bundle.add<PropertiesDefault>();
       bundle.add<ThenWithoutIf>();
       bundle.add<UnevaluatedItemsDefault>();
       bundle.add<UnevaluatedPropertiesDefault>();

src/linter/redundant/properties_default.h

@@ -0,0 +1,30 @@
+class PropertiesDefault final : public Rule {
+public:
+  PropertiesDefault()
+      : Rule{"properties_default",
+             "Setting the `properties` keyword to the empty object "
+             "does not add any further constraint"} {};
+
+  [[nodiscard]] auto
+  condition(const sourcemeta::jsontoolkit::JSON &schema, const std::string &,
+            const std::set<std::string> &vocabularies,
+            const sourcemeta::jsontoolkit::Pointer &) const -> bool override {
+    return contains_any(
+               vocabularies,
+               {"https://json-schema.org/draft/2020-12/vocab/applicator",
+                "https://json-schema.org/draft/2019-09/vocab/applicator",
+                "http://json-schema.org/draft-07/schema#",
+                "http://json-schema.org/draft-06/schema#",
+                "http://json-schema.org/draft-04/schema#",
+                "http://json-schema.org/draft-03/schema#",
+                "http://json-schema.org/draft-02/hyper-schema#",
+                "http://json-schema.org/draft-01/hyper-schema#"}) &&
+           schema.is_object() && schema.defines("properties") &&
+           schema.at("properties").is_object() &&
+           schema.at("properties").empty();
+  }
+
+  auto transform(Transformer &transformer) const -> void override {
+    transformer.erase("properties");
+  }
+};

test/linter/2019_09_test.cc

@@ -823,3 +823,20 @@ TEST(Lint_2019_09, dependent_required_tautology_2) {
 
   EXPECT_EQ(document, expected);
 }
+
+TEST(Lint_2019_09, properties_default) {
+  sourcemeta::jsontoolkit::JSON document =
+      sourcemeta::jsontoolkit::parse(R"JSON({
+    "$schema": "https://json-schema.org/draft/2019-09/schema",
+    "properties": {}
+  })JSON");
+
+  LINT_AND_FIX(document);
+
+  const sourcemeta::jsontoolkit::JSON expected =
+      sourcemeta::jsontoolkit::parse(R"JSON({
+    "$schema": "https://json-schema.org/draft/2019-09/schema"
+  })JSON");
+
+  EXPECT_EQ(document, expected);
+}

test/linter/2020_12_test.cc

@@ -806,3 +806,20 @@ TEST(Lint_2020_12, dependent_required_tautology_2) {
 
   EXPECT_EQ(document, expected);
 }
+
+TEST(Lint_2020_12, properties_default) {
+  sourcemeta::jsontoolkit::JSON document =
+      sourcemeta::jsontoolkit::parse(R"JSON({
+    "$schema": "https://json-schema.org/draft/2020-12/schema",
+    "properties": {}
+  })JSON");
+
+  LINT_AND_FIX(document);
+
+  const sourcemeta::jsontoolkit::JSON expected =
+      sourcemeta::jsontoolkit::parse(R"JSON({
+    "$schema": "https://json-schema.org/draft/2020-12/schema"
+  })JSON");
+
+  EXPECT_EQ(document, expected);
+}

test/linter/draft1_test.cc

@@ -219,3 +219,20 @@ TEST(Lint_draft1, minimum_real_for_integer_1) {
 
   EXPECT_EQ(document, expected);
 }
+
+TEST(Lint_draft1, properties_default) {
+  sourcemeta::jsontoolkit::JSON document =
+      sourcemeta::jsontoolkit::parse(R"JSON({
+    "$schema": "http://json-schema.org/draft-01/schema#",
+    "properties": {}
+  })JSON");
+
+  LINT_AND_FIX(document);
+
+  const sourcemeta::jsontoolkit::JSON expected =
+      sourcemeta::jsontoolkit::parse(R"JSON({
+    "$schema": "http://json-schema.org/draft-01/schema#"
+  })JSON");
+
+  EXPECT_EQ(document, expected);
+}

test/linter/draft2_test.cc

@@ -219,3 +219,20 @@ TEST(Lint_draft2, minimum_real_for_integer_1) {
 
   EXPECT_EQ(document, expected);
 }
+
+TEST(Lint_draft2, properties_default) {
+  sourcemeta::jsontoolkit::JSON document =
+      sourcemeta::jsontoolkit::parse(R"JSON({
+    "$schema": "http://json-schema.org/draft-02/schema#",
+    "properties": {}
+  })JSON");
+
+  LINT_AND_FIX(document);
+
+  const sourcemeta::jsontoolkit::JSON expected =
+      sourcemeta::jsontoolkit::parse(R"JSON({
+    "$schema": "http://json-schema.org/draft-02/schema#"
+  })JSON");
+
+  EXPECT_EQ(document, expected);
+}

test/linter/draft3_test.cc

@@ -268,3 +268,20 @@ TEST(Lint_draft3, dependent_required_tautology_2) {
 
   EXPECT_EQ(document, expected);
 }
+
+TEST(Lint_draft3, properties_default) {
+  sourcemeta::jsontoolkit::JSON document =
+      sourcemeta::jsontoolkit::parse(R"JSON({
+    "$schema": "http://json-schema.org/draft-03/schema#",
+    "properties": {}
+  })JSON");
+
+  LINT_AND_FIX(document);
+
+  const sourcemeta::jsontoolkit::JSON expected =
+      sourcemeta::jsontoolkit::parse(R"JSON({
+    "$schema": "http://json-schema.org/draft-03/schema#"
+  })JSON");
+
+  EXPECT_EQ(document, expected);
+}

test/linter/draft4_test.cc

@@ -322,3 +322,20 @@ TEST(Lint_draft4, dependent_required_tautology_2) {
 
   EXPECT_EQ(document, expected);
 }
+
+TEST(Lint_draft4, properties_default) {
+  sourcemeta::jsontoolkit::JSON document =
+      sourcemeta::jsontoolkit::parse(R"JSON({
+    "$schema": "http://json-schema.org/draft-04/schema#",
+    "properties": {}
+  })JSON");
+
+  LINT_AND_FIX(document);
+
+  const sourcemeta::jsontoolkit::JSON expected =
+      sourcemeta::jsontoolkit::parse(R"JSON({
+    "$schema": "http://json-schema.org/draft-04/schema#"
+  })JSON");
+
+  EXPECT_EQ(document, expected);
+}

test/linter/draft6_test.cc

@@ -473,3 +473,20 @@ TEST(Lint_draft6, dependent_required_tautology_2) {
 
   EXPECT_EQ(document, expected);
 }
+
+TEST(Lint_draft6, properties_default) {
+  sourcemeta::jsontoolkit::JSON document =
+      sourcemeta::jsontoolkit::parse(R"JSON({
+    "$schema": "http://json-schema.org/draft-06/schema#",
+    "properties": {}
+  })JSON");
+
+  LINT_AND_FIX(document);
+
+  const sourcemeta::jsontoolkit::JSON expected =
+      sourcemeta::jsontoolkit::parse(R"JSON({
+    "$schema": "http://json-schema.org/draft-06/schema#"
+  })JSON");
+
+  EXPECT_EQ(document, expected);
+}

test/linter/draft7_test.cc

@@ -564,3 +564,20 @@ TEST(Lint_draft7, dependent_required_tautology_2) {
 
   EXPECT_EQ(document, expected);
 }
+
+TEST(Lint_draft7, properties_default) {
+  sourcemeta::jsontoolkit::JSON document =
+      sourcemeta::jsontoolkit::parse(R"JSON({
+    "$schema": "http://json-schema.org/draft-07/schema#",
+    "properties": {}
+  })JSON");
+
+  LINT_AND_FIX(document);
+
+  const sourcemeta::jsontoolkit::JSON expected =
+      sourcemeta::jsontoolkit::parse(R"JSON({
+    "$schema": "http://json-schema.org/draft-07/schema#"
+  })JSON");
+
+  EXPECT_EQ(document, expected);
+}