Fixes SI-5857.

Override `min` and `max` in `Range` and `NumericRange`
to check if a default `Ordering` for the numeric type
in question is used.
If so, bypass traversal and compute the minimum or
maximum element.

1 files changed, 45 insertions, 0 deletions

diff --git a/test/files/run/t5857.scala b/test/files/run/t5857.scala
new file mode 100644
index 0000000000..bf67bedf54
--- /dev/null
+++ b/test/files/run/t5857.scala
@@ -0,0 +1,45 @@
+
+
+
+object Test {
+  
+  def time[U](b: =>U): Long = {
+    val start = System.currentTimeMillis
+    b
+    val end = System.currentTimeMillis
+    
+    end - start
+  }
+  
+  def main(args: Array[String]) {
+    val sz = 1000000000
+    
+    val range = 1 to sz
+    check { assert(range.min == 1, range.min) }
+    check { assert(range.max == sz, range.max) }
+    
+    val descending = sz to 1 by -1
+    check { assert(descending.min == 1) }
+    check { assert(descending.max == sz) }
+    
+    val numeric = 1.0 to sz.toDouble by 1
+    check { assert(numeric.min == 1.0) }
+    check { assert(numeric.max == sz.toDouble) }
+    
+    val numdesc = sz.toDouble to 1.0 by -1
+    check { assert(numdesc.min == 1.0) }
+    check { assert(numdesc.max == sz.toDouble) }
+  }
+  
+  def check[U](b: =>U) {
+    val exectime = time {
+      b
+    }
+    
+    // whatever it is, it should be less than, say, 250ms
+    // if `max` involves traversal, it takes over 5 seconds on a 3.2GHz i7 CPU
+    //println(exectime)
+    assert(exectime < 250, exectime)
+  }
+  
+}