merge prerelease branch

Author: eli-darkly

ldcontext/context_easyjson.go

@@ -303,6 +303,9 @@ func parseKindOnlyEasyJSON(originalLexer *jlexer.Lexer) (Kind, bool, error) {
 		in.WantColon()
 		if key == ldattr.KindAttr {
 			kind := in.String()
+			if in.Error() == nil && kind == "" {
+				return "", false, errContextKindEmpty
+			}
 			return Kind(kind), true, in.Error()
 		}
 		in.SkipRecursive()

ldcontext/context_unmarshaling.go

@@ -72,7 +72,11 @@ func parseKindOnly(originalReader *jreader.Reader) (Kind, bool, error) {
 	r := *originalReader
 	for obj := r.Object(); obj.Next(); {
 		if string(obj.Name()) == ldattr.KindAttr {
-			return Kind(r.String()), true, r.Error()
+			kind := r.String()
+			if r.Error() == nil && kind == "" {
+				return "", false, errContextKindEmpty
+			}
+			return Kind(kind), true, r.Error()
 			// We can immediately return here and not bother parsing the rest of the JSON object; we'll be
 			// creating another Reader that'll start over with the same byte slice for the second pass.
 		}

ldcontext/context_unmarshaling_test.go

@@ -234,6 +234,7 @@ func contextUnmarshalingTests(t *testing.T, unmarshalFn func(*Context, []byte) e
 
 			`{"kind": "org"}`,             // missing key
 			`{"kind": "user", "key": ""}`, // empty key not allowed in new-style context
+			`{"kind": "", "key": "x"}`,    // empty kind not allowed in new-style context
 			`{"kind": "ørg", "key": "x"}`, // illegal kind
 
 			// wrong type within _meta
@@ -346,6 +347,7 @@ func TestContextReadKindAndKeyOnly(t *testing.T) {
 
 			`{"kind": "org"}`,             // missing key
 			`{"kind": "user", "key": ""}`, // empty key not allowed in new-style context
+			`{"kind": "", "key": "x"}`,    // empty kind not allowed in new-style context
 			`{"kind": "ørg", "key": "x"}`, // illegal kind
 
 			`{"kind": "multi"}`,                                           // multi kind with no kinds

ldcontext/errors.go

@@ -7,6 +7,7 @@ import (
 var (
 	errContextUninitialized              = errors.New("tried to use uninitialized Context")
 	errContextKeyEmpty                   = errors.New("context key must not be empty")
+	errContextKindEmpty                  = errors.New(`context kind cannot be empty`)
 	errContextKindCannotBeKind           = errors.New(`"kind" is not a valid context kind`)
 	errContextKindMultiWithSimpleBuilder = errors.New(`context of kind "multi" must be built with NewMultiBuilder`)
 	errContextKindMultiWithNoKinds       = errors.New("multi-kind context must contain at least one kind")