From 306a6dc81ff1da3191e8035517b4f08b9045ae20 Mon Sep 17 00:00:00 2001
From: Ryan Uber <ru@ryanuber.com>
Date: Mon, 21 Sep 2015 16:20:50 -0700
Subject: [PATCH] command: print a warning if we get 0 evaluated nodes

---
 command/monitor.go      |  5 +++++
 command/monitor_test.go | 11 +++++++++++
 2 files changed, 16 insertions(+)

diff --git a/command/monitor.go b/command/monitor.go
index b72979835..e0b020f20 100644
--- a/command/monitor.go
+++ b/command/monitor.go
@@ -272,6 +272,11 @@ func dumpAllocStatus(ui cli.Ui, alloc *api.Allocation) {
 		alloc.ID, alloc.ClientStatus,
 		alloc.Metrics.NodesFiltered, alloc.Metrics.NodesEvaluated))
 
+	// Print a helpful message if we have an eligibility problem
+	if alloc.Metrics.NodesEvaluated == 0 {
+		ui.Output("  * No nodes were eligible for evaluation")
+	}
+
 	// Print filter info
 	for class, num := range alloc.Metrics.ClassFiltered {
 		ui.Output(fmt.Sprintf("  * Class %q filtered %d nodes", class, num))
diff --git a/command/monitor_test.go b/command/monitor_test.go
index 646b188ae..dbb474561 100644
--- a/command/monitor_test.go
+++ b/command/monitor_test.go
@@ -326,4 +326,15 @@ func TestMonitor_DumpAllocStatus(t *testing.T) {
 	if !strings.Contains(out, `Dimension "cpu" exhausted on 1 nodes`) {
 		t.Fatalf("missing dimension exhaustion\n\n%s", out)
 	}
+	ui.OutputWriter.Reset()
+
+	// Dumping alloc status with no eligible nodes adds a warning
+	alloc.Metrics.NodesEvaluated = 0
+	dumpAllocStatus(ui, alloc)
+
+	// Check the output
+	out = ui.OutputWriter.String()
+	if !strings.Contains(out, "No nodes were eligible") {
+		t.Fatalf("missing eligibility warning\n\n%s", out)
+	}
 }