feat: add version-compare library to compare build-tools versions properly. (#709)

Closes #708

framework/cordova.gradle

@@ -19,6 +19,7 @@
 
 import java.util.regex.Pattern
 import groovy.swing.SwingBuilder
+import com.g00fy2.versioncompare.Version
 
 String doEnsureValueExists(filePath, props, key) {
     if (props.get(key) == null) {
@@ -39,14 +40,15 @@ String doGetProjectTarget() {
     return doEnsureValueExists('project.properties', props, 'target')
 }
 
-String[] getAvailableBuildTools() {
+Version[] getAvailableBuildTools() {
     def buildToolsDir = new File(getAndroidSdkDir(), "build-tools")
     buildToolsDir.list()
-        .findAll { it ==~ /[0-9.]+/ }
+        .collect { new Version(it) } // Invalid inputs will be handled as 0.0.0
-        .sort { a, b -> compareVersions(b, a) }
+        .findAll { it.isHigherThan('0.0.0') }
+        .sort { a, b -> a.isHigherThan(b) ? -1 : 1 }
 }
 
-String doFindLatestInstalledBuildTools(String minBuildToolsVersion) {
+String doFindLatestInstalledBuildTools(String minBuildToolsVersionString) {
     def availableBuildToolsVersions
     try {
         availableBuildToolsVersions = getAvailableBuildTools()
@@ -56,41 +58,20 @@ String doFindLatestInstalledBuildTools(String minBuildToolsVersion) {
     }
     if (availableBuildToolsVersions.length > 0) {
         def highestBuildToolsVersion = availableBuildToolsVersions[0]
-        if (compareVersions(highestBuildToolsVersion, minBuildToolsVersion) < 0) {
+        if (highestBuildToolsVersion.isLowerThan(minBuildToolsVersionString)) {
             throw new RuntimeException(
                 "No usable Android build tools found. Highest installed version is " +
-                highestBuildToolsVersion + "; minimum version required is " +
+                highestBuildToolsVersion.getOriginalString() + "; minimum version required is " +
-                minBuildToolsVersion + ".")
+                minBuildToolsVersionString + ".")
         }
-        highestBuildToolsVersion
+        highestBuildToolsVersion.getOriginalString()
     } else {
         throw new RuntimeException(
             "No installed build tools found. Install the Android build tools version " +
-            minBuildToolsVersion + " or higher.")
+            minBuildToolsVersionString + " or higher.")
     }
 }
 
-// Return the first non-zero result of subtracting version list elements
-// pairwise. If they are all identical, return the difference in length of
-// the two lists.
-int compareVersionList(Collection aParts, Collection bParts) {
-    def pairs = ([aParts, bParts]).transpose()
-    pairs.findResult(aParts.size()-bParts.size()) {it[0] - it[1] != 0 ? it[0] - it[1] : null}
-}
-
-// Compare two version strings, such as "19.0.0" and "18.1.1.0". If all matched
-// elements are identical, the longer version is the largest by this method.
-// Examples:
-//   "19.0.0" > "19"
-//   "19.0.1" > "19.0.0"
-//   "19.1.0" > "19.0.1"
-//   "19" > "18.999.999"
-int compareVersions(String a, String b) {
-    def aParts = a.tokenize('.').collect {it.toInteger()}
-    def bParts = b.tokenize('.').collect {it.toInteger()}
-    compareVersionList(aParts, bParts)
-}
-
 String getAndroidSdkDir() {
     def rootDir = project.rootDir
     def androidSdkDir = null
@@ -203,3 +184,12 @@ ext {
     cdvHelpers.getConfigPreference = { name, defaultValue -> doGetConfigPreference(name, defaultValue) }
 }
 
+buildscript {
+    repositories {
+        jcenter()
+    }
+
+    dependencies {
+        classpath 'com.g00fy2:versioncompare:1.3.1@jar'
+    }
+}