Change required scope of entrypoint from rule to document (#6963)

And automatically change implied `scope` from `rule` to `document` when
no `scope` is provided (on rule metadata).

Fixes #6798

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

compile/compile.go

@@ -255,20 +255,20 @@ func (c *Compiler) WithRegoVersion(v ast.RegoVersion) *Compiler {
 	return c
 }
 
-func addEntrypointsFromAnnotations(c *Compiler, ar []*ast.AnnotationsRef) error {
-	for _, ref := range ar {
+func addEntrypointsFromAnnotations(c *Compiler, arefs []*ast.AnnotationsRef) error {
+	for _, aref := range arefs {
 		var entrypoint ast.Ref
-		scope := ref.Annotations.Scope
+		scope := aref.Annotations.Scope
 
-		if ref.Annotations.Entrypoint {
+		if aref.Annotations.Entrypoint {
 			// Build up the entrypoint path from either package path or rule.
 			switch scope {
 			case "package":
-				if p := ref.GetPackage(); p != nil {
+				if p := aref.GetPackage(); p != nil {
 					entrypoint = p.Path
 				}
-			case "rule":
-				if r := ref.GetRule(); r != nil {
+			case "document":
+				if r := aref.GetRule(); r != nil {
 					entrypoint = r.Ref().GroundPrefix()
 				}
 			default:

compile/compile_test.go

@@ -2106,7 +2106,7 @@ q = true`,
 					Annotations: []*ast.Annotations{
 						{
 							Title:      "My P rule",
-							Scope:      "rule",
+							Scope:      "document",
 							Entrypoint: true,
 						},
 					},
@@ -2366,7 +2366,7 @@ func TestCompilerRegoEntrypointAnnotations(t *testing.T) {
 		wantEntrypoints map[string]struct{}
 	}{
 		{
-			note:        "rule annotation",
+			note:        "implied document scope annotation",
 			entrypoints: []string{},
 			modules: map[string]string{
 				"test.rego": `