fix: don't try to process a non-match as a binary incompatibility.

Author: autonomousapps

src/functionalTest/groovy/com/autonomousapps/jvm/DuplicateClasspathSpec.groovy

@@ -14,6 +14,8 @@ import static com.google.common.truth.Truth.assertThat
 
 final class DuplicateClasspathSpec extends AbstractJvmSpec {
 
+  // TODO(tsr): missing test for when there's duplication and all accesses are in fact compatible.
+
   def "duplicates on the classpath can be fixed (#gradleVersion)"() {
     given:
     def project = new DuplicateClasspathProject()

src/main/kotlin/com/autonomousapps/internal/binary/BinaryCompatibilityChecker.kt

@@ -73,10 +73,14 @@ internal class BinaryCompatibilityChecker(
     val relevantMemberAccesses = context.project.memberAccesses
       .filterToOrderedSet { access -> access.owner in relevantDuplicateClassNames }
 
+    if (relevantMemberAccesses.isEmpty()) return null
+
     val (matchingBinaryClasses, nonMatchingBinaryClasses) = relevantMemberAccesses.mapToSet { access ->
       binaryClassCapability.findMatchingClasses(access)
     }.reduce()
 
+    if (nonMatchingBinaryClasses.isEmpty()) return null
+
     // There must be a compatible BinaryClass.<field|method> for each MemberAccess for the usage to be binary-compatible
     val isBinaryCompatible = relevantMemberAccesses.all { access ->
       when (access) {
@@ -204,11 +208,11 @@ internal class BinaryCompatibilityChecker(
    * it's only called on "relevant" classes. THIS class, however, can, via [findRelevantBinaryClasses].
    */
   private fun BinaryClass.partition(memberAccess: MemberAccess): Pair<BinaryClass?, BinaryClass?> {
-    // There can be only one match
+    // There can be only one match: [0, 1]
     val matchingFields = effectivelyPublicFields.firstOrNull { it.matches(memberAccess) }
     val matchingMethods = effectivelyPublicMethods.firstOrNull { it.matches(memberAccess) }
 
-    // There can be many non-matches
+    // There can be many non-matches: [0, ∞]
     val nonMatchingFields = effectivelyPublicFields.filterToOrderedSet { it.doesNotMatch(memberAccess) }
     val nonMatchingMethods = effectivelyPublicMethods.filterToOrderedSet { it.doesNotMatch(memberAccess) }