Custom rules may skip related_resources (#210)

Don't generate docs link for custom rules. Allow them to
provide their own, but if they don't it should be allowed
to be blank.

Fixes #207

Signed-off-by: Anders Eknert <anders@styra.com>

bundle/regal/result.rego

@@ -35,14 +35,12 @@ fail(chain, details) := violation if {
 	some category, title
 	["custom", "regal", "rules", category, title] = link.path
 
-	# NOTE: consider allowing annotation to override any derived values?
 	annotation := object.union(link.annotations, {
 		"custom": {"category": category},
 		"title": title,
-		"related_resources": _related_resources(link.annotations, category, title),
 	})
 
-	violation := _fail_annotated(annotation, details)
+	violation := _fail_annotated_custom(annotation, details)
 }
 
 _related_resources(annotations, _, _) := annotations.related_resources
@@ -56,7 +54,7 @@ _related_resources(annotations, category, title) := rr if {
 }
 
 _fail_annotated(metadata, details) := violation if {
-	is_object(metadata) # from rego.metadata.rule()
+	is_object(metadata)
 	with_location := object.union(metadata, details)
 	category := with_location.custom.category
 	with_category := object.union(with_location, {
@@ -67,12 +65,24 @@ _fail_annotated(metadata, details) := violation if {
 	without_custom_and_scope := object.remove(with_category, ["custom", "scope"])
 	related_resources := resource_urls(without_custom_and_scope.related_resources, category)
 
-	violation := object.union(
-		object.remove(without_custom_and_scope, ["related_resources"]),
-		{"related_resources": related_resources},
+	violation := json.patch(
+		without_custom_and_scope,
+		[{"op": "replace", "path": "/related_resources", "value": related_resources}],
 	)
 }
 
+_fail_annotated_custom(metadata, details) := violation if {
+	is_object(metadata)
+	with_location := object.union(metadata, details)
+	category := with_location.custom.category
+	with_category := object.union(with_location, {
+		"category": category,
+		"level": config.rule_level(config.for_rule(with_location)),
+	})
+
+	violation := object.remove(with_category, ["custom", "scope"])
+}
+
 fail(metadata, details) := _fail_annotated(metadata, details)
 
 resource_urls(related_resources, category) := [r |

bundle/regal/result_test.rego

@@ -0,0 +1,81 @@
+package regal.result_test
+
+import data.regal.result
+
+test_no_related_resources_in_result_fail_on_custom_rule_unless_provided {
+	chain := [
+		{"path": ["custom", "regal", "rules", "categoy", "name", "report"]},
+		{
+			"annotations": {
+				"scope": "package",
+				"description": "This is a test",
+			},
+			"path": ["custom", "regal", "rules", "categoy", "name"],
+		},
+	]
+
+	violation := result.fail(chain, {})
+
+	violation == {
+		"category": "categoy",
+		"description": "This is a test",
+		"level": "error",
+		"title": "name",
+	}
+}
+
+test_related_resources_in_result_fail_on_custom_rule_when_provided {
+	chain := [
+		{"path": ["custom", "regal", "rules", "categoy", "name", "report"]},
+		{
+			"annotations": {
+				"scope": "package",
+				"description": "This is a test",
+				"related_resources": [{
+					"description": "documentation",
+					"ref": "https://example.com",
+				}],
+			},
+			"path": ["custom", "regal", "rules", "categoy", "name"],
+		},
+	]
+
+	violation := result.fail(chain, {})
+
+	violation == {
+		"category": "categoy",
+		"description": "This is a test",
+		"level": "error",
+		"related_resources": [{
+			"description": "documentation",
+			"ref": "https://example.com",
+		}],
+		"title": "name",
+	}
+}
+
+test_related_resources_generated_by_result_fail_for_builtin_rule {
+	chain := [
+		{"path": ["regal", "rules", "categoy", "name", "report"]},
+		{
+			"annotations": {
+				"scope": "package",
+				"description": "This is a test",
+			},
+			"path": ["regal", "rules", "categoy", "name"],
+		},
+	]
+
+	violation := result.fail(chain, {})
+
+	violation == {
+		"category": "categoy",
+		"description": "This is a test",
+		"level": "error",
+		"related_resources": [{
+			"description": "documentation",
+			"ref": "https://github.com/StyraInc/regal/blob/main/docs/rules/categoy/name.md",
+		}],
+		"title": "name",
+	}
+}

internal/test/rego_test.go

@@ -47,12 +47,12 @@ func TestRunRegoUnitTests(t *testing.T) {
 
 	compiler := compile.NewCompilerWithRegalBuiltins().
 		WithSchemas(compile.SchemaSet(schema)).
-		WithUseTypeCheckAnnotations(true)
+		WithUseTypeCheckAnnotations(true).
+		WithEnablePrintStatements(true)
 
 	runner := tester.NewRunner().
 		SetCompiler(compiler).
 		SetStore(store).
-		CapturePrintOutput(true).
 		SetRuntime(ast.NewTerm(ast.NewObject())).
 		SetBundles(bundle).
 		// TODO: Not needed?