From b67fb19a5e81bd310b2f549ecbce6a8ead352db6 Mon Sep 17 00:00:00 2001
From: Marco Ferrer <35935108+marcoferrer@users.noreply.github.com>
Date: Wed, 9 Jan 2019 23:16:52 -0500
Subject: [PATCH] add support for protoc --xxx_opt flag

---
 .../protobuf/gradle/GenerateProtoTask.groovy  |  8 +++++-
 .../com/google/protobuf/gradle/Utils.groovy   | 28 ++++++++++++++++++-
 2 files changed, 34 insertions(+), 2 deletions(-)

diff --git a/src/main/groovy/com/google/protobuf/gradle/GenerateProtoTask.groovy b/src/main/groovy/com/google/protobuf/gradle/GenerateProtoTask.groovy
index 682a8b8f..07da2971 100644
--- a/src/main/groovy/com/google/protobuf/gradle/GenerateProtoTask.groovy
+++ b/src/main/groovy/com/google/protobuf/gradle/GenerateProtoTask.groovy
@@ -451,7 +451,13 @@ public class GenerateProtoTask extends DefaultTask {
         logger.warn "protoc plugin '${name}' not defined. Trying to use 'protoc-gen-${name}' from system path"
       }
       String pluginOutPrefix = makeOptionsPrefix(plugin.options)
-      baseCmd += "--${name}_out=${pluginOutPrefix}${getOutputDir(plugin)}"
+      // Check if protoc supports opt flag
+      if(Utils.compareProtocVersion(project, "3.2") >= 0 && pluginOutPrefix.length() > 1){
+        baseCmd += "--${name}_opt=${pluginOutPrefix.substring(0, pluginOutPrefix.length() - 1)}"
+        baseCmd += "--${name}_out=${getOutputDir(plugin)}"
+      } else {
+        baseCmd += "--${name}_out=${pluginOutPrefix}${getOutputDir(plugin)}"
+      }
     }
 
     if (generateDescriptorSet) {
diff --git a/src/main/groovy/com/google/protobuf/gradle/Utils.groovy b/src/main/groovy/com/google/protobuf/gradle/Utils.groovy
index d2d5d3d6..f93472a9 100644
--- a/src/main/groovy/com/google/protobuf/gradle/Utils.groovy
+++ b/src/main/groovy/com/google/protobuf/gradle/Utils.groovy
@@ -32,6 +32,7 @@ import com.google.common.base.Preconditions
 import org.apache.commons.lang.StringUtils
 import org.gradle.api.GradleException
 import org.gradle.api.Project
+import org.gradle.api.artifacts.Dependency
 import org.gradle.api.tasks.SourceSet
 import org.gradle.api.tasks.TaskInputs
 import org.gradle.plugins.ide.idea.GenerateIdeaModule
@@ -104,7 +105,32 @@ class Utils {
    * given target version.  Only major and minor versions are checked.  Patch version is ignored.
    */
   static int compareGradleVersion(Project project, String target) {
-    Matcher gv = parseVersionString(project.gradle.gradleVersion)
+    return compareVersions(project.gradle.gradleVersion, target)
+  }
+
+  /**
+   * Returns positive/0/negative if current Protoc version is higher than/equal to/lower than the
+   * given target version.  Only major and minor versions are checked.  Patch version is ignored.
+   */
+  static int compareProtocVersion(Project project, String target) {
+    String protocVersion = null
+    Dependency protocDep = project.configurations
+            .findByName("protobufToolsLocator_protoc").getAllDependencies()[0]
+    if(protocDep != null){
+        protocVersion = protocDep.version
+    }
+    if(protocVersion == null || protocVersion == ""){
+        return -1
+    }
+    return compareVersions(protocVersion, target)
+  }
+
+  /**
+   * Returns positive/0/negative if current version is higher than/equal to/lower than the
+   * given target version.  Only major and minor versions are checked.  Patch version is ignored.
+   */
+  private static int compareVersions(String current, String target) {
+    Matcher gv = parseVersionString(current)
     Matcher tv = parseVersionString(target)
     int majorVersionDiff = gv.group(1).toInteger() - tv.group(1).toInteger()
     if (majorVersionDiff != 0) {