CORE-126: scalafmt enforcement

.git-blame-ignore-revs

@@ -0,0 +1,4 @@
+# .git-blame-ignore-revs
+
+# scalafmt mass change
+3686bb47a5b215733a46c3393a51e950fcaa635f

.github/workflows/format.yaml

@@ -0,0 +1,28 @@
+name: Check formatting for modified files with scalafmt
+
+on:
+  pull_request:
+    paths-ignore: ['**.md']
+
+jobs:
+  format:
+
+    runs-on: ubuntu-latest
+
+    steps:
+
+      - uses: actions/checkout@v4
+        with:
+          fetch-depth: 2
+          ref: ${{ github.event.pull_request.head.sha }}
+
+      - name: Set up JDK 17
+        uses: actions/setup-java@v4
+        with:
+          distribution: 'temurin'
+          java-version: 17
+          cache: sbt
+
+      - name: Check formatting for modified files
+        run: |
+          sbt scalafmtCheckAll

project/Settings.scala

@@ -5,6 +5,7 @@ import Version._
 import sbt.Keys._
 import sbt._
 import sbtassembly.AssemblyPlugin.autoImport._
+import org.scalafmt.sbt.ScalafmtPlugin.autoImport.scalafmtFilter
 
 object Settings {
 
@@ -41,9 +42,14 @@ object Settings {
     assembly / test := {}
   )
 
+  val scalafmtSettings = List(
+    Global / excludeLintKeys += scalafmtFilter,
+    Global / scalafmtFilter := "diff-ref=HEAD^"
+  )
+
   //common settings for all sbt subprojects
   val commonSettings =
-    commonBuildSettings ++ commonAssemblySettings ++ commonTestSettings ++ List(
+    commonBuildSettings ++ commonAssemblySettings ++ commonTestSettings ++ scalafmtSettings ++ List(
     organization  := "org.broadinstitute.dsde.firecloud",
     scalaVersion  := "2.13.15",
     resolvers := proxyResolvers ++: resolvers.value ++: commonResolvers,