Add Xcode version check

konan/konan.properties

@@ -25,8 +25,8 @@ dependencyProfiles = default alt
 airplaneMode = false
 # if true, ignores Xcode version check.
 ignoreXcodeVersionCheck = false
-# Disabled until decided better mechanism.
-# useFixedXcodeVersion = 11.0
+
+minimalXcodeVersion=11.0
 
 downloadingAttempts = 10
 downloadingAttemptIntervalMs = 3000

shared/src/main/kotlin/org/jetbrains/kotlin/konan/target/Apple.kt

@@ -19,6 +19,7 @@ package org.jetbrains.kotlin.konan.target
 import org.jetbrains.kotlin.konan.properties.KonanPropertiesLoader
 import org.jetbrains.kotlin.konan.properties.Properties
 import org.jetbrains.kotlin.konan.util.InternalServer
+import kotlin.math.max
 
 class AppleConfigurablesImpl(
         target: KonanTarget,
@@ -63,19 +64,36 @@ class AppleConfigurablesImpl(
         XcodePartsProvider.InternalServer
     } else {
         val xcode = Xcode.current
-        properties.getProperty("useFixedXcodeVersion")?.let { requiredXcodeVersion ->
-            val currentXcodeVersion = xcode.version
 
-            if (properties.getProperty("ignoreXcodeVersionCheck") != "true" &&
-                    currentXcodeVersion != requiredXcodeVersion) {
-                error("expected Xcode version $requiredXcodeVersion, got $currentXcodeVersion, consider updating " +
-                        "Xcode or use \"ignoreXcodeVersionCheck\" variable in konan.properties")
+        if (properties.getProperty("ignoreXcodeVersionCheck") != "true") {
+            properties.getProperty("minimalXcodeVersion")?.let { minimalXcodeVersion ->
+                val currentXcodeVersion = xcode.version
+                checkXcodeVersion(minimalXcodeVersion, currentXcodeVersion)
             }
         }
 
         XcodePartsProvider.Local(xcode)
     }
 
+    private fun checkXcodeVersion(minimalVersion: String, currentVersion: String) {
+        // Xcode versions contain only numbers (even betas).
+        // But we still split by '-' and whitespaces to take into account versions like 11.2-beta.
+        val minimalVersionParts = minimalVersion.split("(\\s+|\\.|-)".toRegex()).map { it.toIntOrNull() ?: 0 }
+        val currentVersionParts = currentVersion.split("(\\s+|\\.|-)".toRegex()).map { it.toIntOrNull() ?: 0 }
+        val size = max(minimalVersionParts.size, currentVersionParts.size)
+
+        for (i in 0 until size) {
+            val currentPart = currentVersionParts.getOrElse(i) { 0 }
+            val minimalPart = minimalVersionParts.getOrElse(i) { 0 }
+
+            when {
+                currentPart > minimalPart -> return
+                currentPart < minimalPart ->
+                    error("Unsupported Xcode version $currentVersion, minimal supported version is $minimalVersion.")
+            }
+        }
+    }
+
     private sealed class XcodePartsProvider {
         class Local(val xcode: Xcode) : XcodePartsProvider()
         object InternalServer : XcodePartsProvider()