Raise IndexDefect when deleting element at out of bounds index (#17821)

Co-authored-by: Timothee Cour <timothee.cour2@gmail.com>
Co-authored-by: Heiko Nickerl <mail@hnicke.de>
Co-authored-by: Heiko Nickerl <heiko.nickerl@flipapp.de>

tests/gc/gcleak3.nim

@@ -17,14 +17,10 @@ for i in 0..1024:
   s.add(obj)
 
 proc limit*[t](a: var seq[t]) =
-  var loop = s.len() - 512
-  for i in 0..loop:
-    #echo i
-    #GC_fullCollect()
+  while s.len > 0:
     if getOccupiedMem() > 3000_000: quit("still a leak!")
-    s.delete(i)
+    s.delete(0)
 
 s.limit()
-
 echo "no leak: ", getOccupiedMem()
 

tests/stdlib/tsystem.nim

@@ -2,9 +2,10 @@ discard """
   targets: "c cpp js"
 """
 
+import stdtest/testutils
+
 # TODO: in future work move existing `system` tests here, where they belong
 
-import stdtest/testutils
 
 template main =
   block: # closure
@@ -42,5 +43,34 @@ template main =
         # doAssert rawEnv(inner3) != rawEnv(inner1) # because `a` vs `b` # this doesn't hold
     outer()
 
+  block: # system.delete
+    block:
+      var s = @[1]
+      s.delete(0)
+      doAssert s == @[]
+
+    block:
+      var s = @["foo", "bar"]
+      s.delete(1)
+      doAssert s == @["foo"]
+  
+    block:
+      var s: seq[string]
+      doAssertRaises(IndexDefect):
+        s.delete(0)
+
+    block:
+      doAssert not compiles(@["foo"].delete(-1))
+
+    block: # bug #6710
+      var s = @["foo"]
+      s.delete(0)
+      doAssert s == @[]
+  
+    block: # bug #16544: deleting out of bounds index should raise
+      var s = @["foo"]
+      doAssertRaises(IndexDefect):
+        s.delete(1)
+
 static: main()
 main()

tests/system/tsystem_misc.nim

@@ -59,11 +59,6 @@ doAssert high(float) > low(float)
 doAssert high(float32) > low(float32)
 doAssert high(float64) > low(float64)
 
-# bug #6710
-var s = @[1]
-s.delete(0)
-
-
 proc foo(a: openArray[int]) =
   for x in a: echo x