Minimum OS versions, fixed iOS & OS X builds

- Minimum OS versions for iOS, OS X and watchOS
- xcodeTargets => xcodeTargetsIos, xcodeTargetsOsx & xcodeTargetsWatchos
- Extensive refactoring of Podfile updating logic
- Extensive unit tests for all the forgoing changes
- Fixes j2objc-contrib#520

TODO: get watchOS build working

src/main/groovy/com/github/j2objccontrib/j2objcgradle/J2objcConfig.groovy

@@ -622,23 +622,26 @@ class J2objcConfig {
      * <p/>
      * See https://developer.apple.com/library/ios/documentation/DeveloperTools/Conceptual/cross_development/Configuring/configuring.html#//apple_ref/doc/uid/10000163i-CH1-SW2
      */
-    String minIosVersion = '6.0'
+    // Matches the oldest version supported in Xcode 7
+    String minVersionIos = '6.0'
 
     /**
      * The minimum OS X version to build against.  You cannot use APIs that are not supported
      * in this version.
      * <p/>
      * See https://developer.apple.com/library/ios/documentation/DeveloperTools/Conceptual/cross_development/Configuring/configuring.html#//apple_ref/doc/uid/10000163i-CH1-SW2
      */
-    String minOsxVersion = '10.4'
+    // Matches the oldest version supported in Xcode 7
+    String minVersionOsx = '10.4'
 
     /**
      * The minimum Watch OS version to build against.  You cannot use APIs that are not supported
      * in this version.
      * <p/>
      * See https://developer.apple.com/library/ios/documentation/DeveloperTools/Conceptual/cross_development/Configuring/configuring.html#//apple_ref/doc/uid/10000163i-CH1-SW2
      */
-    String minWatchosVersion = '1.0'
+    // Matches the oldest version supported in Xcode 7
+    String minVersionWatchos = '1.0'
 
     // XCODE
     /**
@@ -649,28 +652,54 @@ class J2objcConfig {
      *
      */
     String xcodeProjectDir = null
+
     /**
-     * Xcode app targets that should be linked to the generated library.
+     * iOS app and test Xcode targets to link to the generated libraries.
      *
      * This will automatically add linkage for any target in the specified list
-     * to the generated shared library. This should include any Test and Watch
-     * targets if needed.
+     * to the generated shared libraries. This should include test targets also.
+     */
+    List<String> xcodeTargetsIos = new ArrayList<>()
+    /**
+     * iOS app and test Xcode targets to link to the generated libraries.
      *
-     * If empty (default), it will link all targets defined within the Xcode project.
+     * @param xcodeTargetsIos targets to link to the generated libraries.
      */
-    List<String> xcodeTargets = new ArrayList<>()
+    void xcodeTargetsIos(String... xcodeTargetsIos) {
+        appendArgs(this.xcodeTargetsIos, 'xcodeTargetsIos', xcodeTargetsIos)
+    }
+
     /**
-     * Add targets within Xcode to link to the generated shared library.
+     * OS X app and test Xcode targets that should be linked to the generated libraries.
      *
-     * If this is never called, it will default to linking all targets
-     * to the generated shared library.
+     * This will automatically add linkage for any target in the specified list
+     * to the generated shared libraries. This should include test targets also.
+     */
+    List<String> xcodeTargetsOsx = new ArrayList<>()
+    /**
+     * OS X app and test Xcode targets to link to the generated libraries.
      *
-     * @param xcodeTargets links targets to generated library.
+     * @param xcodeTargetsOsx targets to link to the generated libraries.
      */
-    void xcodeTargets(String... xcodeTargets) {
-        appendArgs(this.xcodeTargets, 'xcodeTargets', xcodeTargets)
+    void xcodeTargetsOsx(String... xcodeTargetsOsx) {
+        appendArgs(this.xcodeTargetsOsx, 'xcodeTargetsOsx', xcodeTargetsOsx)
     }
 
+    /**
+     * watchOS app and test Xcode targets that should be linked to the generated libraries.
+     *
+     * This will automatically add linkage for any target in the specified list
+     * to the generated shared libraries. This should include test targets also.
+     */
+    List<String> xcodeTargetsWatchos = new ArrayList<>()
+    /**
+     * watchOS app and test Xcode targets to link to the generated libraries.
+     *
+     * @param xcodeTargetsWatchos targets to link to the generated libraries.
+     */
+    void xcodeTargetsWatchos(String... xcodeTargetsWatchos) {
+        appendArgs(this.xcodeTargetsWatchos, 'xcodeTargetsWatchos', xcodeTargetsWatchos)
+    }
 
 
     protected boolean finalConfigured = false

src/main/groovy/com/github/j2objccontrib/j2objcgradle/NativeCompilation.groovy

@@ -87,12 +87,12 @@ class NativeCompilation {
                 switch (targetSpec) {
                     case TargetSpec.TARGET_IOS_DEVICE:
                         clangArgs += iphoneClangArgs
-                        clangArgs += ["-miphoneos-version-min=${config.minIosVersion}"]
+                        clangArgs += ["-miphoneos-version-min=${config.minVersionIos}"]
                         linkerArgs += ["-L$j2objcPath/lib"]
                         break
                     case TargetSpec.TARGET_IOS_SIMULATOR:
                         clangArgs += simulatorClangArgs
-                        clangArgs += ["-mios-simulator-version-min=${config.minIosVersion}"]
+                        clangArgs += ["-mios-simulator-version-min=${config.minVersionIos}"]
                         linkerArgs += ["-L$j2objcPath/lib"]
                         break
                     case TargetSpec.TARGET_OSX:

src/main/groovy/com/github/j2objccontrib/j2objcgradle/tasks/PodspecTask.groovy

@@ -68,11 +68,11 @@ class PodspecTask extends DefaultTask {
     String getPodNameRelease() { "j2objc-${project.name}-release" }
 
     @Input
-    String getMinIosVersion() { return J2objcConfig.from(project).getMinIosVersion() }
+    String getMinVersionIos() { return J2objcConfig.from(project).getMinVersionIos() }
     @Input
-    String getMinOsxVersion() { return J2objcConfig.from(project).getMinOsxVersion() }
+    String getMinVersionOsx() { return J2objcConfig.from(project).getMinVersionOsx() }
     @Input
-    String getMinWatchosVersion() { return J2objcConfig.from(project).getMinWatchosVersion() }
+    String getMinVersionWatchos() { return J2objcConfig.from(project).getMinVersionWatchos() }
 
 
     // CocoaPods podspec files that are referenced by the Podfile
@@ -97,19 +97,19 @@ class PodspecTask extends DefaultTask {
         String libDirOsxDebug = relativizeToBuildDir(new File(getDestLibDirFile(), 'x86_64Debug'), project)
         String libDirOsxRelease = relativizeToBuildDir(new File(getDestLibDirFile(), 'x86_64Release'), project)
 
-        validateNumericVersion(getMinIosVersion(), 'minIosVersion')
-        validateNumericVersion(getMinOsxVersion(), 'minOsxVersion')
-        validateNumericVersion(getMinWatchosVersion(), 'minWatchosVersion')
+        validateNumericVersion(getMinVersionIos(), 'minVersionIos')
+        validateNumericVersion(getMinVersionOsx(), 'minVersionOsx')
+        validateNumericVersion(getMinVersionWatchos(), 'minVersionWatchos')
 
         String podspecContentsDebug =
                 genPodspec(getPodNameDebug(), headerIncludePath, resourceIncludePath,
                         libDirIosDebug, libDirOsxDebug, libDirIosDebug,
-                        getMinIosVersion(), getMinOsxVersion(), getMinWatchosVersion(),
+                        getMinVersionIos(), getMinVersionOsx(), getMinVersionWatchos(),
                         getLibName(), getJ2objcHome())
         String podspecContentsRelease =
                 genPodspec(getPodNameRelease(), headerIncludePath, resourceIncludePath,
                         libDirIosRelease, libDirOsxRelease, libDirIosRelease,
-                        getMinIosVersion(), getMinOsxVersion(), getMinWatchosVersion(),
+                        getMinVersionIos(), getMinVersionOsx(), getMinVersionWatchos(),
                         getLibName(), getJ2objcHome())
 
         logger.debug("Writing debug podspec... ${getPodspecDebug()}")