[twirllib] - implementing the missing parts

contrib/twirllib/src/TwirlModule.scala

@@ -35,11 +35,11 @@ trait TwirlModule extends mill.Module {
 
   def twirlAdditionalImports: Seq[String] = Nil
 
-  private def twirlConstructorAnnotations: Seq[String] = Nil
+  def twirlConstructorAnnotations: Seq[String] = Nil
 
-  private def twirlCodec: Codec = Codec(Properties.sourceEncoding)
+  def twirlCodec: Codec = Codec(Properties.sourceEncoding)
 
-  private def twirlInclusiveDot: Boolean = false
+  def twirlInclusiveDot: Boolean = false
 
   def compileTwirl: T[mill.scalalib.api.CompilationResult] = T.persistent {
     TwirlWorkerApi.twirlWorker

contrib/twirllib/src/TwirlWorker.scala

@@ -4,6 +4,7 @@ package twirllib
 import java.io.File
 import java.lang.reflect.Method
 import java.net.URLClassLoader
+import java.nio.charset.Charset
 
 import mill.api.PathRef
 import mill.scalalib.api.CompilationResult
@@ -22,24 +23,29 @@ class TwirlWorker {
 
         // Switched to using the java api because of the hack-ish thing going on later.
         //
-        // * we'll need to construct a collection of additional imports
-        // * it will need to consider the defaults
-        // * and add the user-provided additional imports
+        // * we'll need to construct a collection of additional imports (will need to also include the defaults and add the user-provided additional imports)
+        // * we'll need to construct a collection of constructor annotations// *
         // * the default collection in scala api is a Seq[String]
         // * but it is defined in a different classloader (namely in cl)
         // * so we can not construct our own Seq and pass it to the method - it will be from our classloader, and not compatible
-        // * the java api has a Collection as the type for this param, for which it is much more doable to append things to it using reflection
+        // * the java api uses java collections, manipulating which using reflection is much simpler
         //
-        // NOTE: I tried creating the cl classloader passing the current classloader as the parent:
+        // NOTE: When creating the cl classloader with passing the current classloader as the parent:
         //   val cl = new URLClassLoader(twirlClasspath.map(_.toIO.toURI.toURL).toArray, getClass.getClassLoader)
-        // in that case it was possible to cast the default to a Seq[String], construct our own Seq[String], and pass it to the method invoke- it was compatible.
-        // And the tests passed. But when run in a different mill project, I was getting exceptions like this:
+        // it is possible to cast the default to a Seq[String], construct our own Seq[String], and pass it to the method invoke -
+        // classe will be compatible (the tests passed).
+        // But when run in an actual mill project with this module enabled, there were exceptions like this:
         // scala.reflect.internal.MissingRequirementError: object scala in compiler mirror not found.
 
         val twirlCompilerClass = cl.loadClass("play.japi.twirl.compiler.TwirlCompiler")
 
-        // this one is only to get the codec: Codec parameter default value
-        val twirlScalaCompilerClass = cl.loadClass("play.twirl.compiler.TwirlCompiler")
+        val codecClass = cl.loadClass("scala.io.Codec")
+        val charsetClass = cl.loadClass("java.nio.charset.Charset")
+        val arrayListClass = cl.loadClass("java.util.ArrayList")
+        val hashSetClass = cl.loadClass("java.util.HashSet")
+
+        val codecApplyMethod = codecClass.getMethod("apply", charsetClass)
+        val charsetForNameMethod = charsetClass.getMethod("forName", classOf[java.lang.String])
 
         val compileMethod = twirlCompilerClass.getMethod("compile",
           classOf[java.io.File],
@@ -51,11 +57,9 @@ class TwirlWorker {
           cl.loadClass("scala.io.Codec"),
           classOf[Boolean])
 
-        val arrayListClass = cl.loadClass("java.util.ArrayList")
-        val hashSetClass = cl.loadClass("java.util.HashSet")
+        val defaultImportsMethod = twirlCompilerClass.getField("DEFAULT_IMPORTS")
 
-        val defaultAdditionalImportsMethod = twirlCompilerClass.getField("DEFAULT_IMPORTS")
-        val defaultCodecMethod = twirlScalaCompilerClass.getMethod("compile$default$7")
+        val hashSetConstructor = hashSetClass.getConstructor(cl.loadClass("java.util.Collection"))
 
         val instance = new TwirlWorkerApi {
           override def compileTwirl(source: File,
@@ -66,27 +70,42 @@ class TwirlWorker {
                                     constructorAnnotations: Seq[String],
                                     codec: Codec,
                                     inclusiveDot: Boolean) {
-            val defaultAdditionalImports = defaultAdditionalImportsMethod.get(null) // unmodifiable collection
-            // copying it into a modifiable hash set and adding all additional imports
-            val allAdditionalImports =
-              hashSetClass
-                .getConstructor(cl.loadClass("java.util.Collection"))
-                .newInstance(defaultAdditionalImports)
-                .asInstanceOf[Object]
-            val hashSetAddMethod =
-              allAdditionalImports
-                .getClass
-                .getMethod("add", classOf[Object])
-            additionalImports.foreach(hashSetAddMethod.invoke(allAdditionalImports, _))
-
+            // val defaultImports = play.japi.twirl.compiler.TwirlCompiler.DEFAULT_IMPORTS()
+            // val twirlAdditionalImports = new HashSet(defaultImports)
+            // additionalImports.foreach(twirlAdditionalImports.add)
+            val defaultImports = defaultImportsMethod.get(null) // unmodifiable collection
+            val twirlAdditionalImports = hashSetConstructor.newInstance(defaultImports).asInstanceOf[Object]
+            val hashSetAddMethod = twirlAdditionalImports.getClass.getMethod("add", classOf[Object])
+            additionalImports.foreach(hashSetAddMethod.invoke(twirlAdditionalImports, _))
+
+            // Codec.apply(Charset.forName(codec.charSet.name()))
+            val twirlCodec = codecApplyMethod.invoke(null, charsetForNameMethod.invoke(null, codec.charSet.name()))
+
+            // val twirlConstructorAnnotations = new ArrayList()
+            // constructorAnnotations.foreach(twirlConstructorAnnotations.add)
+            val twirlConstructorAnnotations = arrayListClass.newInstance().asInstanceOf[Object]
+            val arrayListAddMethod = twirlConstructorAnnotations.getClass.getMethod("add", classOf[Object])
+            constructorAnnotations.foreach(arrayListAddMethod.invoke(twirlConstructorAnnotations, _))
+
+            // JavaAPI
+            //   public static Optional<File> compile(
+            //   File source,
+            //   File sourceDirectory,
+            //   File generatedDirectory,
+            //   String formatterType,
+            //   Collection<String> additionalImports,
+            //   List<String> constructorAnnotations,
+            //   Codec codec,
+            //   boolean inclusiveDot
+            // )
             val o = compileMethod.invoke(null, source,
               sourceDirectory,
               generatedDirectory,
               formatterType,
-              allAdditionalImports,
-              arrayListClass.newInstance().asInstanceOf[Object], // empty list seems to be the default
-              defaultCodecMethod.invoke(null),
-              Boolean.box(false)
+              twirlAdditionalImports,
+              twirlConstructorAnnotations,
+              twirlCodec,
+              Boolean.box(inclusiveDot)
             )
           }
         }

contrib/twirllib/test/resources/hello-world-inclusive-dot/core/views/hello.scala.html

@@ -0,0 +1,8 @@
+@this(title: String)
+@wrapper {
+    <html>
+        <body>
+            <h1>@title</h1>
+        </body>
+    </html>
+}

contrib/twirllib/test/resources/hello-world-inclusive-dot/core/views/wrapper.scala.html

@@ -0,0 +1,5 @@
+@(content: Html)
+
+@defining("test") { className =>
+    <div class="@className">@content</div>
+}

contrib/twirllib/test/resources/hello-world/core/views/hello.scala.html

@@ -1,4 +1,4 @@
-@(title: String)
+@this(title: String)
 <html>
     <body>
         <h1>@title</h1>

contrib/twirllib/test/src/HelloWorldTests.scala

@@ -13,28 +13,40 @@ object HelloWorldTests extends TestSuite {
   }
 
   trait HelloWorldModule extends mill.twirllib.TwirlModule {
-    def twirlVersion = "1.0.0"
-    override def twirlAdditionalImports: Seq[String] = additionalImports
+
+    def twirlVersion = "1.3.15"
+
   }
 
   object HelloWorld extends HelloBase {
 
     object core extends HelloWorldModule {
-      override def twirlVersion = "1.3.15"
+      override def twirlAdditionalImports: Seq[String] = testAdditionalImports
+      override def twirlConstructorAnnotations: Seq[String] = testConstructorAnnotations
     }
+
   }
 
-  val resourcePath: os.Path = os.pwd / 'contrib / 'twirllib / 'test / 'resources / "hello-world"
+  object HelloWorldWithInclusiveDot extends HelloBase {
+
+    object core extends HelloWorldModule {
+      override def twirlInclusiveDot: Boolean = true
+    }
+
+  }
 
   def workspaceTest[T](
       m: TestUtil.BaseModule,
-      resourcePath: os.Path = resourcePath
+      resourcePathSuffix: String
   )(t: TestEvaluator => T)(implicit tp: TestPath): T = {
     val eval = new TestEvaluator(m)
     os.remove.all(m.millSourcePath)
     os.remove.all(eval.outPath)
     os.makeDir.all(m.millSourcePath / os.up)
-    os.copy(resourcePath, m.millSourcePath)
+    os.copy(
+      os.pwd / 'contrib / 'twirllib / 'test / 'resources / resourcePathSuffix,
+      m.millSourcePath
+    )
     t(eval)
   }
 
@@ -52,15 +64,20 @@ object HelloWorldTests extends TestSuite {
     "import _root_.play.twirl.api.Xml"
   )
 
-  def additionalImports: Seq[String] = Seq(
+  def testAdditionalImports: Seq[String] = Seq(
     "mill.twirl.test.AdditionalImport1._",
     "mill.twirl.test.AdditionalImport2._"
   )
 
+  def testConstructorAnnotations = Seq(
+  "@org.springframework.stereotype.Component()",
+  "@something.else.Thing()"
+  )
+
   def tests: Tests = Tests {
     'twirlVersion - {
 
-      'fromBuild - workspaceTest(HelloWorld) { eval =>
+      'fromBuild - workspaceTest(HelloWorld, "hello-world") { eval =>
         val Right((result, evalCount)) =
           eval.apply(HelloWorld.core.twirlVersion)
 
@@ -70,7 +87,7 @@ object HelloWorldTests extends TestSuite {
         )
       }
     }
-    'compileTwirl - workspaceTest(HelloWorld) { eval =>
+    'compileTwirl - workspaceTest(HelloWorld, "hello-world") { eval =>
       val Right((result, evalCount)) = eval.apply(HelloWorld.core.compileTwirl)
 
       val outputFiles = os.walk(result.classes.path).filter(_.last.endsWith(".scala"))
@@ -86,8 +103,43 @@ object HelloWorldTests extends TestSuite {
         evalCount > 0,
         outputFiles.forall { p =>
           val lines = os.read.lines(p).map(_.trim)
-          (expectedDefaultImports ++ additionalImports.map(s => s"import $s")).forall(lines.contains)
-        }
+          (expectedDefaultImports ++ testAdditionalImports.map(s => s"import $s")).forall(lines.contains)
+        },
+        outputFiles.filter(_.toString().contains("hello.template.scala")).forall { p =>
+          val lines = os.read.lines(p).map(_.trim)
+          val expectedClassDeclaration = s"class hello ${testConstructorAnnotations.mkString}"
+          lines.exists(_.startsWith(expectedClassDeclaration))
+        },
+
+      )
+
+      // don't recompile if nothing changed
+      val Right((_, unchangedEvalCount)) =
+        eval.apply(HelloWorld.core.compileTwirl)
+
+      assert(unchangedEvalCount == 0)
+    }
+    'compileTwirlInclusiveDot - workspaceTest(HelloWorldWithInclusiveDot, "hello-world-inclusive-dot") { eval =>
+      val Right((result, evalCount)) = eval.apply(HelloWorldWithInclusiveDot.core.compileTwirl)
+
+      val outputFiles = os.walk(result.classes.path).filter(_.last.endsWith(".scala"))
+      val expectedClassfiles = compileClassfiles.map( name =>
+        eval.outPath / 'core / 'compileTwirl / 'dest / 'html / name.toString().replace(".template.scala", "$$TwirlInclusiveDot.template.scala")
+      )
+
+      println(s"outputFiles: $outputFiles")
+
+      assert(
+        result.classes.path == eval.outPath / 'core / 'compileTwirl / 'dest,
+        outputFiles.nonEmpty,
+        outputFiles.forall(expectedClassfiles.contains),
+        outputFiles.size == 2,
+        evalCount > 0,
+        outputFiles.filter(_.toString().contains("hello.template.scala")).forall { p =>
+          val lines = os.read.lines(p).map(_.trim)
+          lines.exists(_.contains("$$TwirlInclusiveDot"))
+        },
+
       )
 
       // don't recompile if nothing changed

docs/pages/9 - Contrib Modules.md

@@ -168,8 +168,10 @@ object app extends ScalaModule with TwirlModule {
 #### Configuration options
 
 * `def twirlVersion: T[String]` (mandatory) - the version of the twirl compiler to use, like "1.3.15"
-* `def twirlAdditionalImports: Seq[String] = Nil` - the additional imports that will be added by twirl compiler to the top
-  of all templates
+* `def twirlAdditionalImports: Seq[String] = Nil` - the additional imports that will be added by twirl compiler to the top of all templates
+* `def twirlConstructorAnnotations: Seq[String] = Nil` - annotations added to the generated classes' constructors (note it only applies to templates with `@this(...)` constructors) 
+* `def twirlCodec = Codec(Properties.sourceEncoding)` - the codec used to generate the files (the default is the same sbt plugin uses) 
+* `def twirlInclusiveDot: Boolean = false`  
 
 #### Details