Merge pull request #696 from raboof/consider-missing-signature-equiva…

…lent-to-nongeneric
lightbend-labs · Apr 29, 2022 · 0b42f3a · 0b42f3a
2 parents 1f5c4ce + 6e017db
commit 0b42f3a
Show file tree

Hide file tree

Showing 3 changed files with 12 additions and 7 deletions.
diff --git a/core/src/main/scala/com/typesafe/tools/mima/core/Signature.scala b/core/src/main/scala/com/typesafe/tools/mima/core/Signature.scala
@@ -20,9 +20,18 @@ class Signature(private val signature: String) {
   }
 
   def matches(newer: Signature, isConstructor: Boolean): Boolean = {
-    return (signature == newer.signature) ||
-      (isConstructor && hasMatchingCtorSig(newer.signature)) ||
-      canonicalized == newer.canonicalized
+    // If the signature is identical obviously it matches
+    (signature == newer.signature) ||
+    // Consider missing signatures identical to non-generic ones.
+    // This is particularly helpful because between Scala 3.1.1 and 3.1.2 the compiler
+    // started emitting signatures for non-generic methods. Incompatibilities for those
+    // will be caught through mismatching descriptors anyway.
+    (signature == "" && newer.signature.indexOf('<') == -1) ||
+    (newer.signature == "" && signature.indexOf('<') == -1) ||
+    // Special rules for constructors
+    (isConstructor && hasMatchingCtorSig(newer.signature)) ||
+    // Also match when the signature only differs in the name of a type parameter
+    canonicalized == newer.canonicalized
   }
 
   // Special case for scala#7975

diff --git a/...ts/src/test/java-class-static-varargs-to-scala-object-annotated-varargs-ok/problems-3.txt b/...ts/src/test/java-class-static-varargs-to-scala-object-annotated-varargs-ok/problems-3.txt
diff --git a/functional-tests/src/test/trait-abstract-var-becomes-concrete-ok/problems-3.txt b/functional-tests/src/test/trait-abstract-var-becomes-concrete-ok/problems-3.txt