Berry extend range(lower, upper, incr) to arbitrary increment (#19120)

CHANGELOG.md

@@ -15,6 +15,7 @@ All notable changes to this project will be documented in this file.
 ### Changed
 - ESP32 shutter driver support up to 16 shutters (#18295)
 - Configuration backup and restore now backup and restore ``.xdrvsetXXX`` files too (#18295)
+- Berry extend `range(lower, upper, incr)` to arbitrary increment
 
 ### Fixed
 

lib/libesp32/berry/src/be_rangelib.c

@@ -11,31 +11,67 @@
 
 static int m_init(bvm *vm)
 {
+    int argc = be_top(vm);
     be_pushvalue(vm, 2);
     be_setmember(vm, 1, "__lower__");
     be_pop(vm, 1);
     be_pushvalue(vm, 3);
     be_setmember(vm, 1, "__upper__");
+    int incr = 1;   /* default increment is '1' */
+    if (argc >= 4) {
+        incr = be_toint(vm, 4);
+        if (incr == 0) { be_raise(vm, "value_error", "increment cannot be zero"); }
+    }
+    be_pushint(vm, incr);
+    be_setmember(vm, 1, "__incr__");
     be_return_nil(vm);
 }
 
 static int m_tostring(bvm *vm)
 {
-    be_pushstring(vm, "(");
+    be_getmember(vm, 1, "__incr__");
-    be_getmember(vm, 1, "__lower__");
+    int incr = be_toint(vm, -1);
-    be_tostring(vm, -1);
-    be_strconcat(vm, -2);
-    be_pop(vm, 1);
-    be_pushstring(vm, "..");
-    be_strconcat(vm, -2);
-    be_pop(vm, 1);
-    be_getmember(vm, 1, "__upper__");
-    be_tostring(vm, -1);
-    be_strconcat(vm, -2);
-    be_pop(vm, 1);
-    be_pushstring(vm, ")");
-    be_strconcat(vm, -2);
     be_pop(vm, 1);
+    if (incr == 1) {
+        be_pushstring(vm, "(");
+        be_getmember(vm, 1, "__lower__");
+        be_tostring(vm, -1);
+        be_strconcat(vm, -2);
+        be_pop(vm, 1);
+        be_pushstring(vm, "..");
+        be_strconcat(vm, -2);
+        be_pop(vm, 1);
+        be_getmember(vm, 1, "__upper__");
+        be_tostring(vm, -1);
+        be_strconcat(vm, -2);
+        be_pop(vm, 1);
+        be_pushstring(vm, ")");
+        be_strconcat(vm, -2);
+        be_pop(vm, 1);
+    } else {
+        be_pushstring(vm, "range(");
+        be_getmember(vm, 1, "__lower__");
+        be_tostring(vm, -1);
+        be_strconcat(vm, -2);
+        be_pop(vm, 1);
+        be_pushstring(vm, ", ");
+        be_strconcat(vm, -2);
+        be_pop(vm, 1);
+        be_getmember(vm, 1, "__upper__");
+        be_tostring(vm, -1);
+        be_strconcat(vm, -2);
+        be_pop(vm, 1);
+        be_pushstring(vm, ", ");
+        be_strconcat(vm, -2);
+        be_pop(vm, 1);
+        be_getmember(vm, 1, "__incr__");
+        be_tostring(vm, -1);
+        be_strconcat(vm, -2);
+        be_pop(vm, 1);
+        be_pushstring(vm, ")");
+        be_strconcat(vm, -2);
+        be_pop(vm, 1);
+    }
     be_return(vm);
 }
 
@@ -51,13 +87,27 @@ static int m_lower(bvm *vm)
     be_return(vm);
 }
 
+static int m_incr(bvm *vm)
+{
+    be_getmember(vm, 1, "__incr__");
+    be_return(vm);
+}
+
 static int m_setrange(bvm *vm)
 {
+    int argc = be_top(vm);
     be_pushvalue(vm, 2);
     be_setmember(vm, 1, "__lower__");
     be_pop(vm, 1);
     be_pushvalue(vm, 3);
     be_setmember(vm, 1, "__upper__");
+    int incr = 1;   /* default increment is '1' */
+    if (argc >= 4) {
+        incr = be_toint(vm, 4);
+        if (incr == 0) { be_raise(vm, "value_error", "increment cannot be zero"); }
+    }
+    be_pushint(vm, incr);
+    be_setmember(vm, 1, "__incr__");
     be_return_nil(vm);
 }
 
@@ -68,25 +118,30 @@ static int iter_closure(bvm *vm)
     bntvclos *func = var_toobj(vm->cf->func);
     bvalue *uv0 = be_ntvclos_upval(func, 0)->value;
     bvalue *uv1 = be_ntvclos_upval(func, 1)->value;
+    bvalue *uv2 = be_ntvclos_upval(func, 2)->value;
     bint lower = var_toint(uv0); /* upvalue[0] => lower */
     bint upper = var_toint(uv1); /* upvalue[1] => upper */
-    if (lower > upper) {
+    bint incr = var_toint(uv2); /* upvalue[2] => incr */
+    if ((incr > 0 && lower > upper) || (incr < 0 && lower < upper)) {
         be_stop_iteration(vm);
     }
-    var_toint(uv0) = lower + 1; /* set upvale[0] */
+    var_toint(uv0) = lower + incr; /* set upvale[0] */
     be_pushint(vm, lower); /* push the return value */
     be_return(vm);
 }
 
 static int m_iter(bvm *vm)
 {
-    be_pushntvclosure(vm, iter_closure, 2);
+    be_pushntvclosure(vm, iter_closure, 3);
     be_getmember(vm, 1, "__lower__");
     be_setupval(vm, -2, 0);
     be_pop(vm, 1);
     be_getmember(vm, 1, "__upper__");
     be_setupval(vm, -2, 1);
     be_pop(vm, 1);
+    be_getmember(vm, 1, "__incr__");
+    be_setupval(vm, -2, 2);
+    be_pop(vm, 1);
     be_return(vm);
 }
 
@@ -96,6 +151,7 @@ void be_load_rangelib(bvm *vm)
     static const bnfuncinfo members[] = {
         { "__lower__", NULL },
         { "__upper__", NULL },
+        { "__incr__", NULL },
         { "init", m_init },
         { "tostring", m_tostring },
         { "lower", m_lower },
@@ -111,10 +167,12 @@ void be_load_rangelib(bvm *vm)
 class be_class_range (scope: global, name: range) {
     __lower__, var
     __upper__, var
+    __incr__, var
     init, func(m_init)
     tostring, func(m_tostring)
     lower, func(m_lower)
     upper, func(m_upper)
+    incr, func(m_incr)
     setrange, func(m_setrange)
     iter, func(m_iter)
 }

lib/libesp32/berry/tests/range.be

@@ -0,0 +1,39 @@
+# test for ranges
+
+# expand a range object as list
+def expand(iter)
+    var ret = []
+    for i: iter
+        ret.push(i)
+    end
+    return ret
+end
+
+assert(expand(0..5) == [0, 1, 2, 3, 4, 5])
+assert(expand(0..0) == [0])
+assert(expand(5..0) == [])
+var r = 1..5
+assert(r.lower() == 1)
+assert(r.upper() == 5)
+assert(r.incr() == 1)
+
+assert(expand(range(0,5)) == [0, 1, 2, 3, 4, 5])
+assert(expand(range(0,5,2)) == [0, 2, 4])
+assert(expand(range(0,5,12)) == [0])
+assert(expand(range(0,5,-1)) == [])
+
+assert(expand(range(5,0,-1)) == [5, 4, 3, 2, 1, 0])
+assert(expand(range(5,0,-2)) == [5, 3, 1])
+assert(expand(range(5,5,-2)) == [5])
+assert(expand(range(0,5,-2)) == [])
+
+def assert_value_error(c)
+    try
+        compile(c)()
+        assert(false, 'unexpected execution flow')
+    except 'value_error' as e, m
+    end
+end
+
+# range with increment zero shoud raise an error
+assert_value_error("range(1,2,0)")