Added regression tests and bugfixes for stacks.scad

stacks.scad

@@ -99,26 +99,26 @@ function stack_top(stack,n=undef) =
 //   If `n` is given, returns a list of the `n` stack items at and above depth `depth`.
 // Arguments:
 //   stack = The stack to read from.
-//   depth = The depth of the stack item to read.  Default: 1
+//   depth = The depth of the stack item to read.  Default: 0
 //   n = The number of stack items to return.  Default: undef (Return only the stack item at `depth`)
 // Example:
 //   stack = [2,3,4,5,6,7,8,9];
 //   item = stack_peek(stack);  // Returns: 9
 //   item2 = stack_peek(stack, 3);  // Returns: 7
 //   list = stack_peek(stack, 6, 4);  // Returns: [4,5,6,7]
-function stack_peek(stack,depth=1,n=undef) =
+function stack_peek(stack,depth=0,n=undef) =
 	assert(is_list(stack))
 	assert(is_num(depth))
-	assert(depth>0)
+	assert(depth>=0)
 	let(stacksize = len(stack))
 	assert(stacksize>=depth, "stack underflow")
 	is_undef(n)? (
-		stack[stacksize-depth]
+		stack[stacksize-depth-1]
 	) : (
 		assert(is_num(n))
 		assert(n>=0)
-		assert(n<depth)
-		[for (i=[0:1:n-1]) stack[stacksize-depth+i]]
+		assert(n<=depth+1)
+		[for (i=[0:1:n-1]) stack[stacksize-1-depth+i]]
 	);
 
 

tests/test_stacks.scad

@@ -0,0 +1,69 @@
+include <BOSL2/std.scad>
+include <BOSL2/stacks.scad>
+
+
+module test_stack_init() {
+	assert(stack_init()==[]);
+}
+test_stack_init();
+
+
+module test_stack_empty() {
+	assert(stack_empty([]));
+	assert(!stack_empty([3]));
+	assert(!stack_empty([2,4,8]));
+}
+test_stack_empty();
+
+
+module test_stack_depth() {
+	assert(stack_depth([]) == 0);
+	assert(stack_depth([3]) == 1);
+	assert(stack_depth([2,4,8]) == 3);
+}
+test_stack_depth();
+
+
+module test_stack_top() {
+	assert(stack_top([]) == undef);
+	assert(stack_top([3,5,7,9]) == 9);
+	assert(stack_top([3,5,7,9], 3) == [5,7,9]);
+}
+test_stack_top();
+
+
+module test_stack_peek() {
+	s = [8,5,4,3,2,3,7];
+	assert(stack_peek(s,0) == 7);
+	assert(stack_peek(s,2) == 2);
+	assert(stack_peek(s,2,1) == [2]);
+	assert(stack_peek(s,2,3) == [2,3,7]);
+}
+test_stack_peek();
+
+
+module test_stack_push() {
+	s1 = stack_init();
+	s2 = stack_push(s1, "Foo");
+	assert(s2==["Foo"]);
+	s3 = stack_push(s2, "Bar");
+	assert(s3==["Foo","Bar"]);
+	s4 = stack_push(s3, "Baz");
+	assert(s4==["Foo","Bar","Baz"]);
+}
+test_stack_push();
+
+
+module test_stack_pop() {
+	q = ["Foo", "Bar", "Baz", "Qux"];
+	q1 = stack_pop(q);
+	assert(q1 == ["Foo", "Bar", "Baz"]);
+	q2 = stack_pop(q,2);
+	assert(q2 == ["Foo", "Bar"]);
+	q3 = stack_pop(q,3);
+	assert(q3 == ["Foo"]);
+}
+test_stack_pop();
+
+
+// vim: noexpandtab tabstop=4 shiftwidth=4 softtabstop=4 nowrap

version.scad

@@ -8,7 +8,7 @@
 //////////////////////////////////////////////////////////////////////
 
 
-BOSL_VERSION = [2,0,7];
+BOSL_VERSION = [2,0,8];
 
 
 // Section: BOSL Library Version Functions