Simple BuildInfo plugin (#325)

* Simple BuildInfo plugin
* BuildInfo readme
   include other known yet external plugins
* Add tests

1 files changed, 112 insertions, 0 deletions

diff --git a/contrib/buildinfo/test/src/mill/contrib/BuildInfoTests.scala b/contrib/buildinfo/test/src/mill/contrib/BuildInfoTests.scala
new file mode 100644
index 00000000..9e1549de
--- /dev/null
+++ b/contrib/buildinfo/test/src/mill/contrib/BuildInfoTests.scala
@@ -0,0 +1,112 @@
+package mill.contrib
+
+import ammonite.ops._
+import java.util.jar.JarFile
+import mill._
+import mill.define.Target
+import mill.eval.Result._
+import mill.eval.{Evaluator, Result}
+import mill.modules.Assembly
+import mill.scalalib.publish.VersionControl
+import mill.scalalib.publish._
+import mill.util.{TestEvaluator, TestUtil}
+import scala.collection.JavaConverters._
+import utest._
+import utest.framework.TestPath
+
+
+object BuildInfoTests extends TestSuite {
+
+  val scalaVersionString = "2.12.4"
+  trait BuildInfoModule extends TestUtil.BaseModule with scalalib.ScalaModule with BuildInfo {
+    def millSourcePath =  TestUtil.getSrcPathBase() / millOuterCtx.enclosing.split('.')
+    def scalaVersion = scalaVersionString
+  }
+
+  object EmptyBuildInfo extends BuildInfoModule
+
+  object BuildInfo extends BuildInfoModule {
+    def buildInfoMembers=T{
+      Map(
+        "scalaVersion" -> scalaVersion(),
+      )
+    }
+  }
+
+  object BuildInfoSettings extends BuildInfoModule {
+    def buildInfoPackageName = Some("foo")
+    def buildInfoObjectName = "bar"
+    def buildInfoMembers=T{
+      Map(
+        "scalaVersion" -> scalaVersion()
+      )
+    }
+  }
+
+  val resourcePath = pwd / 'contrib / 'buildinfo / 'test / 'resources / "buildinfo"
+
+  def workspaceTest[T, M <: TestUtil.BaseModule](m: M, resourcePath: Path = resourcePath)
+                                                (t: TestEvaluator[M] => T)
+                                                (implicit tp: TestPath): T = {
+    val eval = new TestEvaluator(m)
+    rm(m.millSourcePath)
+    rm(eval.outPath)
+    mkdir(m.millSourcePath / up)
+    cp(resourcePath, m.millSourcePath)
+    t(eval)
+  }
+
+  def tests: Tests = Tests {
+
+    'buildinfo - {
+      'createSourcefile - workspaceTest(BuildInfo){ eval =>
+        val expected = 
+          s"""|
+              |object BuildInfo {
+              |  def scalaVersion = "2.12.4"
+              |}""".stripMargin
+        val Right((result, evalCount)) = eval.apply(BuildInfo.buildInfo)
+        assert(
+          result.head.path == eval.outPath / 'buildInfo / 'dest / "BuildInfo.scala" &&
+            exists(result.head.path) &&
+            read! result.head.path == expected
+        )
+      }
+
+      'notCreateEmptySourcefile - workspaceTest(EmptyBuildInfo){ eval =>
+        val Right((result, evalCount)) = eval.apply(EmptyBuildInfo.buildInfo)
+        assert(
+          result.isEmpty &&
+            !exists(eval.outPath / 'buildInfo / 'dest / "BuildInfo.scala")
+        )
+      }
+
+      'supportCustomSettings - workspaceTest(BuildInfoSettings){ eval =>
+        val expected = 
+          s"""|package foo
+              |object bar {
+              |  def scalaVersion = "2.12.4"
+              |}""".stripMargin
+        val Right((result, evalCount)) = eval.apply(BuildInfoSettings.buildInfo)
+        assert(
+          result.head.path == eval.outPath / 'buildInfo / 'dest / "BuildInfo.scala" &&
+            exists(result.head.path) &&
+            read! result.head.path == expected
+        )
+      }
+
+      'compile - workspaceTest(BuildInfo){ eval =>
+        val Right((result, evalCount)) = eval.apply(BuildInfo.compile)
+        assert(true)
+      }
+
+      'run - workspaceTest(BuildInfo){ eval =>
+        val runResult = eval.outPath / "hello-mill"
+        val Right((result, evalCount)) = eval.apply(BuildInfo.run(runResult.toString))
+        assert(
+          exists(runResult),
+          read(runResult) == scalaVersionString)
+      }
+    }
+  }
+}