improving twirl (#473)

* improving twirl support: default imports, better `compileTwirl().classes` value

* twirl module doc edits

2 files changed, 45 insertions, 12 deletions

diff --git a/contrib/twirllib/test/resources/hello-world/core/views/wrapper.scala.html b/contrib/twirllib/test/resources/hello-world/core/views/wrapper.scala.html
new file mode 100644
index 00000000..af1f5d8e
--- /dev/null
+++ b/contrib/twirllib/test/resources/hello-world/core/views/wrapper.scala.html
@@ -0,0 +1,5 @@
+@(content: Html)
+
+@defining("test") { className =>
+    <div class="@className">@content</div>
+}
\ No newline at end of file
diff --git a/contrib/twirllib/test/src/mill/twirllib/HelloWorldTests.scala b/contrib/twirllib/test/src/mill/twirllib/HelloWorldTests.scala
index 8ef6ee3e..804fd5a1 100644
--- a/contrib/twirllib/test/src/mill/twirllib/HelloWorldTests.scala
+++ b/contrib/twirllib/test/src/mill/twirllib/HelloWorldTests.scala
@@ -5,14 +5,18 @@ import mill.util.{TestEvaluator, TestUtil}
 import utest.framework.TestPath
 import utest.{TestSuite, Tests, assert, _}
 
+import scala.io.Codec
+
 object HelloWorldTests extends TestSuite {
 
   trait HelloBase extends TestUtil.BaseModule {
-    override def millSourcePath: Path = TestUtil.getSrcPathBase() / millOuterCtx.enclosing.split('.')
+    override def millSourcePath: Path =
+      TestUtil.getSrcPathBase() / millOuterCtx.enclosing.split('.')
   }
 
   trait HelloWorldModule extends mill.twirllib.TwirlModule {
     def twirlVersion = "1.0.0"
+    override def twirlAdditionalImports: Seq[String] = additionalImports
   }
 
   object HelloWorld extends HelloBase {
@@ -22,11 +26,13 @@ object HelloWorldTests extends TestSuite {
     }
   }
 
-  val resourcePath: Path = pwd / 'contrib / 'twirllib / 'test / 'resources / "hello-world"
+  val resourcePath
+    : Path = pwd / 'contrib / 'twirllib / 'test / 'resources / "hello-world"
 
-  def workspaceTest[T](m: TestUtil.BaseModule, resourcePath: Path = resourcePath)
-                      (t: TestEvaluator => T)
-                      (implicit tp: TestPath): T = {
+  def workspaceTest[T](
+      m: TestUtil.BaseModule,
+      resourcePath: Path = resourcePath
+  )(t: TestEvaluator => T)(implicit tp: TestPath): T = {
     val eval = new TestEvaluator(m)
     rm(m.millSourcePath)
     rm(eval.outPath)
@@ -36,14 +42,30 @@ object HelloWorldTests extends TestSuite {
   }
 
   def compileClassfiles: Seq[RelPath] = Seq[RelPath](
-    "hello.template.scala"
+    "hello.template.scala",
+    "wrapper.template.scala"
+  )
+
+  def expectedDefaultImports: Seq[String] = Seq(
+    "import _root_.play.twirl.api.TwirlFeatureImports._",
+    "import _root_.play.twirl.api.TwirlHelperImports._",
+    "import _root_.play.twirl.api.Html",
+    "import _root_.play.twirl.api.JavaScript",
+    "import _root_.play.twirl.api.Txt",
+    "import _root_.play.twirl.api.Xml"
+  )
+
+  def additionalImports: Seq[String] = Seq(
+    "mill.twirl.test.AdditionalImport1._",
+    "mill.twirl.test.AdditionalImport2._"
   )
 
   def tests: Tests = Tests {
     'twirlVersion - {
 
       'fromBuild - workspaceTest(HelloWorld) { eval =>
-        val Right((result, evalCount)) = eval.apply(HelloWorld.core.twirlVersion)
+        val Right((result, evalCount)) =
+          eval.apply(HelloWorld.core.twirlVersion)
 
         assert(
           result == "1.3.15",
@@ -54,20 +76,26 @@ object HelloWorldTests extends TestSuite {
     'compileTwirl - workspaceTest(HelloWorld) { eval =>
       val Right((result, evalCount)) = eval.apply(HelloWorld.core.compileTwirl)
 
-      val outputFiles = ls.rec(result.classes.path)
+      val outputFiles = ls.rec(result.classes.path).filter(_.name.endsWith(".scala"))
       val expectedClassfiles = compileClassfiles.map(
         eval.outPath / 'core / 'compileTwirl / 'dest / 'html / _
       )
+
       assert(
-        result.classes.path == eval.outPath / 'core / 'compileTwirl / 'dest / 'html,
+        result.classes.path == eval.outPath / 'core / 'compileTwirl / 'dest,
         outputFiles.nonEmpty,
         outputFiles.forall(expectedClassfiles.contains),
-        outputFiles.size == 1,
-        evalCount > 0
+        outputFiles.size == 2,
+        evalCount > 0,
+        outputFiles.forall { p =>
+          val lines = p.getLines(Codec.UTF8).map(_.trim)
+          (expectedDefaultImports ++ additionalImports.map(s => s"import $s")).forall(lines.contains)
+        }
       )
 
       // don't recompile if nothing changed
-      val Right((_, unchangedEvalCount)) = eval.apply(HelloWorld.core.compileTwirl)
+      val Right((_, unchangedEvalCount)) =
+        eval.apply(HelloWorld.core.compileTwirl)
 
       assert(unchangedEvalCount == 0)
     }