Enhance API/messages around BinaryVersion / JvmMetadataVersion

core/compiler.common/src/org/jetbrains/kotlin/serialization/deserialization/IncompatibleVersionErrorData.kt

@@ -9,6 +9,8 @@ import org.jetbrains.kotlin.name.ClassId
 
 data class IncompatibleVersionErrorData<out T>(
     val actualVersion: T,
+    val compilerVersion: T,
+    val languageVersion: T,
     val expectedVersion: T,
     val filePath: String,
     val classId: ClassId

core/descriptors.jvm/src/org/jetbrains/kotlin/load/kotlin/DeserializedDescriptorResolver.kt

@@ -85,7 +85,12 @@ class DeserializedDescriptorResolver {
         get() {
             if (skipMetadataVersionCheck || classHeader.metadataVersion.isCompatible(ownMetadataVersion)) return null
             return IncompatibleVersionErrorData(
-                classHeader.metadataVersion, maxOf(ownMetadataVersion.prev(), JvmMetadataVersion.INSTANCE), location, classId
+                actualVersion = classHeader.metadataVersion,
+                compilerVersion = JvmMetadataVersion.INSTANCE,
+                languageVersion = ownMetadataVersion,
+                expectedVersion = ownMetadataVersion.lastSupportedVersionWithThisLanguageVersion(classHeader.metadataVersion.isStrictSemantics),
+                filePath = location,
+                classId = classId
             )
         }
 

core/metadata.jvm/src/org/jetbrains/kotlin/metadata/jvm/deserialization/JvmMetadataVersion.kt

@@ -14,6 +14,13 @@ import org.jetbrains.kotlin.metadata.deserialization.BinaryVersion
 class JvmMetadataVersion(versionArray: IntArray, val isStrictSemantics: Boolean) : BinaryVersion(*versionArray) {
     constructor(vararg numbers: Int) : this(numbers, isStrictSemantics = false)
 
+    fun lastSupportedVersionWithThisLanguageVersion(isStrictSemantics: Boolean): JvmMetadataVersion {
+        // * Compiler of deployVersion X (INSTANCE) with LV Y (metadataVersionFromLanguageVersion)
+        //   * can read metadata with version <= max(X+1, Y)
+        val forwardCompatibility = if (isStrictSemantics) INSTANCE else INSTANCE_NEXT
+        return if (forwardCompatibility.newerThan(this)) forwardCompatibility else this
+    }
+
     override fun isCompatibleWithCurrentCompilerVersion(): Boolean {
         return isCompatibleInternal(INSTANCE_NEXT)
     }
@@ -21,10 +28,7 @@ class JvmMetadataVersion(versionArray: IntArray, val isStrictSemantics: Boolean)
     fun isCompatible(metadataVersionFromLanguageVersion: JvmMetadataVersion): Boolean {
         // Special case for bootstrap: 1.8 can read 2.0
         if (major == 2 && minor == 0 && INSTANCE.major == 1 && INSTANCE.minor == 8) return true
-        // * Compiler of deployVersion X (INSTANCE) with LV Y (metadataVersionFromLanguageVersion)
-        //   * can read metadata with version <= max(X+1, Y)
-        val forwardCompatibility = if (isStrictSemantics) INSTANCE else INSTANCE_NEXT
-        val limitVersion = maxOf(forwardCompatibility, metadataVersionFromLanguageVersion)
+        val limitVersion = metadataVersionFromLanguageVersion.lastSupportedVersionWithThisLanguageVersion(isStrictSemantics)
         return isCompatibleInternal(limitVersion)
     }
 
@@ -34,24 +38,28 @@ class JvmMetadataVersion(versionArray: IntArray, val isStrictSemantics: Boolean)
         // The same for 0.*
         if (major == 0) return false
         // Otherwise we just compare with the given limitVersion
-        return this <= limitVersion
+        return !newerThan(limitVersion)
     }
 
-    fun next(): JvmMetadataVersion {
-        if (minor < 9 || major > 1) return JvmMetadataVersion(major, minor + 1, 0)
-        return JvmMetadataVersion(2, 0, 0)
-    }
+    fun next(): JvmMetadataVersion =
+        if (major == 1 && minor == 9) JvmMetadataVersion(2, 0, 0)
+        else JvmMetadataVersion(major, minor + 1, 0)
 
-    fun prev(): JvmMetadataVersion {
-        if (minor > 0) return JvmMetadataVersion(major, minor - 1, 0)
-        return JvmMetadataVersion(major - 1, 9, 0)
+    private fun newerThan(other: JvmMetadataVersion): Boolean {
+        return when {
+            major > other.major -> true
+            major < other.major -> false
+            minor > other.minor -> true
+            else -> false
+        }
     }
 
     companion object {
         @JvmField
         val INSTANCE = JvmMetadataVersion(1, 8, 0)
 
-        private val INSTANCE_NEXT = INSTANCE.next()
+        @JvmField
+        val INSTANCE_NEXT = INSTANCE.next()
 
         @JvmField
         val INVALID_VERSION = JvmMetadataVersion()

core/metadata/src/org/jetbrains/kotlin/metadata/deserialization/BinaryVersion.kt

@@ -14,7 +14,7 @@ package org.jetbrains.kotlin.metadata.deserialization
  * - Patch version can be increased freely and is only supposed to be used for debugging. Increase the patch version when you
  *   make a change to binaries which is both forward- and backward compatible.
  */
-abstract class BinaryVersion(private vararg val numbers: Int) : Comparable<BinaryVersion> {
+abstract class BinaryVersion(private vararg val numbers: Int) {
     val major: Int = numbers.getOrNull(0) ?: UNKNOWN
     val minor: Int = numbers.getOrNull(1) ?: UNKNOWN
     val patch: Int = numbers.getOrNull(2) ?: UNKNOWN
@@ -87,18 +87,6 @@ abstract class BinaryVersion(private vararg val numbers: Int) : Comparable<Binar
         return result
     }
 
-    override fun compareTo(other: BinaryVersion): Int {
-        return when {
-            major > other.major -> 1
-            major < other.major -> -1
-            minor > other.minor -> 1
-            minor < other.minor -> -1
-            patch > other.patch -> 1
-            patch < other.patch -> -1
-            else -> 0
-        }
-    }
-
     companion object {
         const val MAX_LENGTH = 1024
         private const val UNKNOWN = -1