[PATCH] D91462: [YAMLIO] Correctly diagnose empty alias/anchor

[Scott Linder via Phabricator via llvm-commits]

scott.linder created this revision.
Herald added subscribers: llvm-commits, dexonsmith, hiraditya.
Herald added a project: LLVM.
scott.linder requested review of this revision.

The `Range` of an alias/anchor token includes the leading `&` or `*`,
but it is skipped while parsing the name. The check for an empty name
fails to account for the skipped leading character and so the error is
never hit.

Fix the off-by-one and add a couple regression tests.


Repository:
  rG LLVM Github Monorepo

https://reviews.llvm.org/D91462

Files:
  llvm/lib/Support/YAMLParser.cpp
  llvm/unittests/Support/YAMLIOTest.cpp


Index: llvm/unittests/Support/YAMLIOTest.cpp
===================================================================
--- llvm/unittests/Support/YAMLIOTest.cpp
+++ llvm/unittests/Support/YAMLIOTest.cpp
@@ -3101,3 +3101,15 @@
   EXPECT_FALSE(yin2.setCurrentDocument());
   EXPECT_TRUE(yin2.error());
 }
+
+TEST(YAMLIO, TestEmptyAlias) {
+  Input yin("&");
+  EXPECT_FALSE(yin.setCurrentDocument());
+  EXPECT_TRUE(yin.error());
+}
+
+TEST(YAMLIO, TestEmptyAnchor) {
+  Input yin("*");
+  EXPECT_FALSE(yin.setCurrentDocument());
+  EXPECT_TRUE(yin.error());
+}
Index: llvm/lib/Support/YAMLParser.cpp
===================================================================
--- llvm/lib/Support/YAMLParser.cpp
+++ llvm/lib/Support/YAMLParser.cpp
@@ -1423,7 +1423,7 @@
     ++Column;
   }
 
-  if (Start == Current) {
+  if (Start + 1 == Current) {
     setError("Got empty alias or anchor", Start);
     return false;
   }


-------------- next part --------------
A non-text attachment was scrubbed...
Name: D91462.305262.patch
Type: text/x-patch
Size: 910 bytes
Desc: not available
URL: <http://lists.llvm.org/pipermail/llvm-commits/attachments/20201113/ea608197/attachment.bin>