Fallback output

cli/src/main/scala/coursier/cli/TermDisplay.scala

@@ -10,15 +10,58 @@ import coursier.Files.Logger
 import scala.annotation.tailrec
 import scala.collection.mutable.ArrayBuffer
 
-class TermDisplay(out: Writer) extends Logger {
+class TermDisplay(
+  out: Writer,
+  var fallbackMode: Boolean = false
+) extends Logger {
 
   private val ansi = new Ansi(out)
   private var width = 80
   private val refreshInterval = 1000 / 60
+  private val fallbackRefreshInterval = 1000
+
   private val lock = new AnyRef
   private val t = new Thread("TermDisplay") {
     override def run() = lock.synchronized {
+
       val baseExtraWidth = width / 5
+
+      def reflowed(url: String, info: Info) = {
+        val pctOpt = info.pct.map(100.0 * _)
+        val extra =
+          if (info.length.isEmpty && info.downloaded == 0L)
+            ""
+          else
+            s"(${pctOpt.map(pct => f"$pct%.2f %%, ").mkString}${info.downloaded}${info.length.map(" / " + _).mkString})"
+
+        val total = url.length + 1 + extra.length
+        val (url0, extra0) =
+          if (total >= width) { // or > ? If equal, does it go down 2 lines?
+          val overflow = total - width + 1
+
+            val extra0 =
+              if (extra.length > baseExtraWidth)
+                extra.take((baseExtraWidth max (extra.length - overflow)) - 1) + "…"
+              else
+                extra
+
+            val total0 = url.length + 1 + extra0.length
+            val overflow0 = total0 - width + 1
+
+            val url0 =
+              if (total0 >= width)
+                url.take(((width - baseExtraWidth - 1) max (url.length - overflow0)) - 1) + "…"
+              else
+                url
+
+            (url0, extra0)
+          } else
+            (url, extra)
+
+        (url0, extra0)
+      }
+
+
       @tailrec def helper(lineCount: Int): Unit =
         Option(q.poll(100L, TimeUnit.MILLISECONDS)) match {
           case None => helper(lineCount)
@@ -35,36 +78,8 @@ class TermDisplay(out: Writer) extends Logger {
 
             for ((url, info) <- downloads0) {
               assert(info != null, s"Incoherent state ($url)")
-              val pctOpt = info.pct.map(100.0 * _)
-              val extra =
-                if (info.length.isEmpty && info.downloaded == 0L)
-                  ""
-                else
-                  s"(${pctOpt.map(pct => f"$pct%.2f %%, ").mkString}${info.downloaded}${info.length.map(" / " + _).mkString})"
 
-              val total = url.length + 1 + extra.length
-              val (url0, extra0) =
-                if (total >= width) { // or > ? If equal, does it go down 2 lines?
-                  val overflow = total - width + 1
-
-                  val extra0 =
-                    if (extra.length > baseExtraWidth)
-                      extra.take((baseExtraWidth max (extra.length - overflow)) - 1) + "…"
-                    else
-                      extra
-
-                  val total0 = url.length + 1 + extra0.length
-                  val overflow0 = total0 - width + 1
-
-                  val url0 =
-                    if (total0 >= width)
-                      url.take(((width - baseExtraWidth - 1) max (url.length - overflow0)) - 1) + "…"
-                    else
-                      url
-
-                  (url0, extra0)
-                } else
-                  (url, extra)
+              val (url0, extra0) = reflowed(url, info)
 
               ansi.clearLine(2)
               out.write(s"$url0 $extra0\n")
@@ -88,15 +103,54 @@ class TermDisplay(out: Writer) extends Logger {
             helper(downloads0.length)
         }
 
-      helper(0)
+
+      @tailrec def fallbackHelper(previous: Set[String]): Unit =
+        Option(q.poll(100L, TimeUnit.MILLISECONDS)) match {
+          case None => fallbackHelper(previous)
+          case Some(Left(())) => // poison pill
+          case Some(Right(())) =>
+            val downloads0 = downloads.synchronized {
+              downloads
+                .toVector
+                .map { url => url -> infos.get(url) }
+                .sortBy { case (_, info) => - info.pct.sum }
+            }
+
+            var displayedSomething = false
+            for ((url, info) <- downloads0 if previous(url)) {
+              assert(info != null, s"Incoherent state ($url)")
+
+              val (url0, extra0) = reflowed(url, info)
+
+              displayedSomething = true
+              out.write(s"$url0 $extra0\n")
+            }
+
+            if (displayedSomething)
+              out.write("\n")
+
+            out.flush()
+            Thread.sleep(fallbackRefreshInterval)
+            fallbackHelper(previous ++ downloads0.map { case (url, _) => url })
+          }
+
+      if (fallbackMode)
+        fallbackHelper(Set.empty)
+      else
+        helper(0)
     }
   }
 
   t.setDaemon(true)
 
   def init(): Unit = {
-    width = TTY.consoleDim("cols")
-    ansi.clearLine(2)
+    try {
+      width = TTY.consoleDim("cols")
+      ansi.clearLine(2)
+    } catch { case _: Exception =>
+      fallbackMode = true
+    }
+
     t.start()
   }
 
@@ -123,6 +177,12 @@ class TermDisplay(out: Writer) extends Logger {
     val prev = infos.putIfAbsent(url, Info(0L, None))
     assert(prev == null)
 
+    if (fallbackMode) {
+      // FIXME What about concurrent accesses to out from the thread above?
+      out.write(s"Downloading $url\n")
+      out.flush()
+    }
+
     downloads.synchronized {
       downloads.append(url)
     }
@@ -150,6 +210,12 @@ class TermDisplay(out: Writer) extends Logger {
       downloads -= url
     }
 
+    if (fallbackMode) {
+      // FIXME What about concurrent accesses to out from the thread above?
+      out.write(s"Downloaded $url\n")
+      out.flush()
+    }
+
     val info = infos.remove(url)
     assert(info != null)
 

plugin/src/main/scala/coursier/CoursierPlugin.scala

@@ -36,18 +36,10 @@ object CoursierPlugin extends AutoPlugin {
   ) ++ sys.props
 
   private def createLogger() = Some {
-    if (sys.env.get("COURSIER_NO_TERM").nonEmpty)
-      new coursier.Files.Logger {
-        override def downloadingArtifact(url: String, file: File): Unit = {
-          println(s"$url\n -> $file")
-        }
-        override def downloadedArtifact(url: String, success: Boolean): Unit = {
-          println(s"$url: ${if (success) "Success" else "Failed"}")
-        }
-        def init() = {}
-      }
-    else
-      new TermDisplay(new OutputStreamWriter(System.err))
+    new TermDisplay(
+      new OutputStreamWriter(System.err),
+      fallbackMode = sys.env.get("COURSIER_NO_TERM").nonEmpty
+    )
   }