Automatically publish SNAPSHOTs on pushes to master (#1955)

Uses sbt-ci-release for automation

.travis.yml

@@ -3,6 +3,11 @@ sudo: false
 
 jdk: openjdk8
 
+branches:
+  only:
+    - master
+    - /^\d+\.\d+\.x$/
+
 cache:
   directories:
     $HOME/.cache/coursier
@@ -25,8 +30,10 @@ before_script:
   - if [ $OLDEST_SHARED == $OLDEST_COMMIT ]; then git fetch --unshallow; fi
 
 stages:
-  - prepare
-  - test
+  - name: prepare
+  - name: test
+  - name: release
+    if: ((branch = master) OR (branch =~ /^\d+\.\d+\.x$/)) AND (type = push) AND (NOT fork)
 
 # We do not use the built-in tests as generated by using multiple Scala
 # versions because the cache is not shared between stages with any
@@ -136,3 +143,7 @@ jobs:
       script:
         - benchmark/scripts/benchmark_cold_compile.py -N 2 --designs regress/ICache.fir --versions HEAD
         - benchmark/scripts/find_heap_bound.py -- -cp firrtl*jar firrtl.stage.FirrtlMain -i regress/ICache.fir -o out -X verilog
+    # run ci-release only if previous stages passed
+    - stage: release
+      name: "Publish SNAPSHOT release"
+      script: sbt ci-release

build.sbt

@@ -90,7 +90,7 @@ lazy val antlrSettings = Seq(
 )
 
 lazy val publishSettings = Seq(
-  publishMavenStyle := true,
+  // publishMavenStyle and publishTo handled by sbt-ci-release
   publishArtifact in Test := false,
   pomIncludeRepository := { x => false },
   // Don't add 'scm' elements if we have a git.remoteRepo definition,
@@ -114,15 +114,6 @@ lazy val publishSettings = Seq(
         <url>http://www.eecs.berkeley.edu/~jrb/</url>
       </developer>
     </developers>,
-  publishTo := {
-    val v = version.value
-    val nexus = "https://oss.sonatype.org/"
-    if (v.trim.endsWith("SNAPSHOT")) {
-      Some("snapshots" at nexus + "content/repositories/snapshots")
-    } else {
-      Some("releases" at nexus + "service/local/staging/deploy/maven2")
-    }
-  }
 )
 
 

project/plugins.sbt

@@ -24,4 +24,6 @@ addSbtPlugin("com.thoughtworks.sbt-api-mappings" % "sbt-api-mappings" % "3.0.0")
 
 addSbtPlugin("org.scalameta" % "sbt-scalafmt" % "2.4.0")
 
+addSbtPlugin("com.geirsson" % "sbt-ci-release" % "1.5.4")
+
 libraryDependencies += "com.github.os72" % "protoc-jar" % "3.11.4"