Fix ./mill init example download paths (#5516)

Also add a simple smoketest that captiures the logs make sure the
download path isn't malformed

Author: lihaoyi

dist/package.mill

@@ -235,13 +235,13 @@ object `package` extends MillJavaModule with DistModule {
     for (path <- examplePaths()) yield {
       val example = path.subRelativeTo(BuildCtx.workspaceRoot)
       val artifactName = example.segments.mkString("-")
-      (path, s"${build.dist.artifactFileNamePrefix()}-$artifactName")
+      s"${build.dist.artifactFileNamePrefix()}-$artifactName"
     }
   }
 
   def exampleZips: T[Seq[PathRef]] = Task {
     examplePathRefs().zip(exampleArtifactNames()).map {
-      case (pr, (examplePath, exampleStr)) =>
+      case (pr, exampleStr) =>
         os.copy(pr.path, Task.dest / exampleStr, createFolders = true)
         val ignoreErrorsOnCI = Task.dest / exampleStr / "ignoreErrorsOnCI"
         if (os.exists(ignoreErrorsOnCI)) os.remove(ignoreErrorsOnCI)

libs/init/test/src/mill/init/InitModuleTests.scala

@@ -19,69 +19,89 @@ object InitModuleTests extends TestSuite {
 
   override def tests: Tests = Tests {
 
-    test("init") {
-      test("no args") {
-        val outStream = new ByteArrayOutputStream()
-        UnitTester(
-          initmodule,
-          null,
-          outStream = new PrintStream(outStream, true),
-          errStream = new PrintStream(OutputStream.nullOutputStream(), true)
-        ).scoped { evaluator =>
-
-          val results = evaluator.evaluator.execute(Seq(initmodule.init(None))).executionResults
-
-          assert(results.transitiveFailing.size == 0)
-
-          val mill.api.ExecResult.Success(Val(value)) = results.results.head: @unchecked
-          val consoleShown = outStream.toString
-
-          val examplesList: Seq[String] = value.asInstanceOf[Seq[String]]
-          assert(
-            consoleShown.startsWith(initmodule.msg),
-            examplesList.forall(_.nonEmpty)
-          )
-        }
+    test("no args") {
+      val outStream = new ByteArrayOutputStream()
+      UnitTester(
+        initmodule,
+        null,
+        outStream = new PrintStream(outStream, true),
+        errStream = new PrintStream(OutputStream.nullOutputStream(), true)
+      ).scoped { evaluator =>
+
+        val results = evaluator.evaluator.execute(Seq(initmodule.init(None))).executionResults
+
+        assert(results.transitiveFailing.size == 0)
+
+        val mill.api.ExecResult.Success(Val(value)) = results.results.head: @unchecked
+        val consoleShown = outStream.toString
+
+        val examplesList: Seq[String] = value.asInstanceOf[Seq[String]]
+        assert(
+          consoleShown.startsWith(initmodule.msg),
+          examplesList.forall(_.nonEmpty)
+        )
       }
-      test("non existing example") {
-        val outStream = new ByteArrayOutputStream()
-        val errStream = new ByteArrayOutputStream()
-        UnitTester(
-          initmodule,
-          null,
-          outStream = new PrintStream(outStream, true),
-          errStream = new PrintStream(errStream, true)
-        ).scoped { evaluator =>
-
-          val nonExistingModuleId = "nonExistingExampleId"
-          val results = evaluator.evaluator.execute(Seq(
-            initmodule.init(Some(nonExistingModuleId))
-          )).executionResults
-          assert(results.transitiveFailing.size == 1)
-          val err = errStream.toString
-
-          def check(): Unit =
-            try assert(err.contains(initmodule.moduleNotExistMsg(nonExistingModuleId)))
-            catch {
-              case ex: utest.AssertionError =>
-                pprint.err.log(outStream)
-                pprint.err.log(errStream)
-                throw ex
-            }
-
-          try check()
+    }
+    test("non existing example") {
+      val outStream = new ByteArrayOutputStream()
+      val errStream = new ByteArrayOutputStream()
+      UnitTester(
+        initmodule,
+        null,
+        outStream = new PrintStream(outStream, true),
+        errStream = new PrintStream(errStream, true)
+      ).scoped { evaluator =>
+
+        val nonExistingModuleId = "nonExistingExampleId"
+        val results = evaluator.evaluator.execute(Seq(
+          initmodule.init(Some(nonExistingModuleId))
+        )).executionResults
+        assert(results.transitiveFailing.size == 1)
+        val err = errStream.toString
+
+        def check(): Unit =
+          try assert(err.contains(initmodule.moduleNotExistMsg(nonExistingModuleId)))
           catch {
-            case ex: utest.AssertionError if Properties.isWin =>
-              // On Windows, it seems there can be a delay until the messages land in errStream,
-              // it's worth retrying
-              ex.printStackTrace(System.err)
-              val waitFor = 2.seconds
-              System.err.println(s"Caught $ex, trying again in $waitFor")
-              Thread.sleep(waitFor.toMillis)
-              check()
+            case ex: utest.AssertionError =>
+              pprint.err.log(outStream)
+              pprint.err.log(errStream)
+              throw ex
           }
+
+        try check()
+        catch {
+          case ex: utest.AssertionError if Properties.isWin =>
+            // On Windows, it seems there can be a delay until the messages land in errStream,
+            // it's worth retrying
+            ex.printStackTrace(System.err)
+            val waitFor = 2.seconds
+            System.err.println(s"Caught $ex, trying again in $waitFor")
+            Thread.sleep(waitFor.toMillis)
+            check()
         }
       }
     }
+    test("example-zip") {
+      val outStream = new java.io.ByteArrayOutputStream()
+      UnitTester(
+        initmodule,
+        null,
+        outStream = new PrintStream(outStream, true),
+        errStream = new PrintStream(OutputStream.nullOutputStream(), true)
+      ).scoped { evaluator =>
+
+        val results = evaluator.evaluator.execute(
+          Seq(initmodule.init(Some("scalalib/basic/1-simple")))
+        ).executionResults
+
+        val expected =
+          "Downloading example from https://repo1.maven.org/maven2/com/lihaoyi/mill-dist/SNAPSHOT/mill-dist-SNAPSHOT-example-scalalib-basic-1-simple.zip."
+
+        // Make sure the download URL logged to the terminal looks reasonable
+        assert(outStream.toString().contains(expected))
+        // This should fail because there is no SNAPSHOT version published to maven central
+        assert(results.results.flatMap(_.asFailing).nonEmpty)
+      }
+    }
   }
 }