From 6d3e05469211e0896efebf593cfd3af9003fa364 Mon Sep 17 00:00:00 2001
From: Julius Volz <julius@soundcloud.com>
Date: Thu, 10 Sep 2015 01:37:05 +0200
Subject: [PATCH] Fix bool modifier in recording rules and printing.

Fixes https://github.com/prometheus/prometheus/issues/1065
---
 promql/printer.go      | 7 ++++++-
 promql/printer_test.go | 3 +++
 2 files changed, 9 insertions(+), 1 deletion(-)

diff --git a/promql/printer.go b/promql/printer.go
index 99025ccd9..44b05f149 100644
--- a/promql/printer.go
+++ b/promql/printer.go
@@ -146,6 +146,11 @@ func (node *AggregateExpr) String() string {
 }
 
 func (node *BinaryExpr) String() string {
+	returnBool := ""
+	if node.ReturnBool {
+		returnBool = " BOOL"
+	}
+
 	matching := ""
 	vm := node.VectorMatching
 	if vm != nil && len(vm.On) > 0 {
@@ -157,7 +162,7 @@ func (node *BinaryExpr) String() string {
 			matching += fmt.Sprintf(" GROUP_RIGHT(%s)", vm.Include)
 		}
 	}
-	return fmt.Sprintf("%s %s%s %s", node.LHS, node.Op, matching, node.RHS)
+	return fmt.Sprintf("%s %s%s%s %s", node.LHS, node.Op, returnBool, matching, node.RHS)
 }
 
 func (node *Call) String() string {
diff --git a/promql/printer_test.go b/promql/printer_test.go
index 9a86c96db..8b3f4154e 100644
--- a/promql/printer_test.go
+++ b/promql/printer_test.go
@@ -30,6 +30,9 @@ func TestExprString(t *testing.T) {
 		{
 			in: `sum(task:errors:rate10s{job="s"}) BY (code) KEEP_COMMON`,
 		},
+		{
+			in: `up > BOOL 0`,
+		},
 	}
 
 	for _, test := range inputs {