From 46c1ba92492e9257aba6418403161072d640cb29 Mon Sep 17 00:00:00 2001
From: Bob Nystrom <robert@stuffwithstuff.com>
Date: Mon, 20 Jan 2014 13:20:22 -0800
Subject: [PATCH] Fix #2. Finish implementing Range.

Covers error and edge cases and fully tested now.
---
 src/wren_core.c                               | 43 ++++++++++++++-----
 src/wren_value.c                              |  3 +-
 src/wren_value.h                              |  5 ++-
 .../range/exclusive_range_wrong_rhs_type.wren |  1 +
 test/range/floating_point.wren                | 31 +++++++++++++
 test/range/from.wren                          |  6 ---
 .../range/inclusive_range_wrong_rhs_type.wren |  1 +
 test/range/is_inclusive.wren                  |  5 +++
 test/range/iterate.wren                       | 29 ++++++++++++-
 test/range/iterate_from_float.wren            | 18 ++++++++
 test/range/max.wren                           |  8 ++--
 test/range/min.wren                           | 11 +++--
 test/range/to.wren                            | 18 ++++----
 test/range/to_string.wren                     |  7 +++
 14 files changed, 148 insertions(+), 38 deletions(-)
 create mode 100644 test/range/exclusive_range_wrong_rhs_type.wren
 create mode 100644 test/range/floating_point.wren
 create mode 100644 test/range/inclusive_range_wrong_rhs_type.wren
 create mode 100644 test/range/is_inclusive.wren
 create mode 100644 test/range/iterate_from_float.wren
 create mode 100644 test/range/to_string.wren

diff --git a/src/wren_core.c b/src/wren_core.c
index 173f8ba3..e263792e 100644
--- a/src/wren_core.c
+++ b/src/wren_core.c
@@ -491,22 +491,22 @@ DEF_NATIVE(num_bitwiseNot)
 
 DEF_NATIVE(num_dotDot)
 {
-  // TODO: Check arg type.
+  if (!validateNum(vm, args, 1, "Right hand side of range")) return PRIM_ERROR;
+
   double from = AS_NUM(args[0]);
   double to = AS_NUM(args[1]);
 
-  RETURN_VAL(wrenNewRange(vm, from, to));
+  RETURN_VAL(wrenNewRange(vm, from, to, true));
 }
 
 DEF_NATIVE(num_dotDotDot)
 {
-  // TODO: Check arg type.
+  if (!validateNum(vm, args, 1, "Right hand side of range")) return PRIM_ERROR;
+
   double from = AS_NUM(args[0]);
+  double to = AS_NUM(args[1]);
 
-  // TODO: Is this how we want half-open ranges to work?
-  double to = AS_NUM(args[1]) - 1;
-
-  RETURN_VAL(wrenNewRange(vm, from, to));
+  RETURN_VAL(wrenNewRange(vm, from, to, false));
 }
 
 DEF_NATIVE(object_eqeq)
@@ -560,10 +560,19 @@ DEF_NATIVE(range_max)
   RETURN_NUM(fmax(range->from, range->to));
 }
 
+DEF_NATIVE(range_isInclusive)
+{
+  ObjRange* range = AS_RANGE(args[0]);
+  RETURN_BOOL(range->isInclusive);
+}
+
 DEF_NATIVE(range_iterate)
 {
   ObjRange* range = AS_RANGE(args[0]);
 
+  // Special case: empty range.
+  if (range->from == range->to && !range->isInclusive) RETURN_FALSE;
+
   // Start the iteration.
   if (IS_NULL(args[1])) RETURN_NUM(range->from);
 
@@ -571,9 +580,21 @@ DEF_NATIVE(range_iterate)
 
   double iterator = AS_NUM(args[1]);
 
-  if (iterator >= range->to) RETURN_FALSE;
+  // Iterate towards [to] from [from].
+  if (range->from < range->to)
+  {
+    iterator++;
+    if (iterator > range->to) RETURN_FALSE;
+  }
+  else
+  {
+    iterator--;
+    if (iterator < range->to) RETURN_FALSE;
+  }
 
-  RETURN_NUM(AS_NUM(args[1]) + 1);
+  if (!range->isInclusive && iterator == range->to) RETURN_FALSE;
+
+  RETURN_NUM(iterator);
 }
 
 DEF_NATIVE(range_iteratorValue)
@@ -586,7 +607,8 @@ DEF_NATIVE(range_toString)
 {
   char buffer[51];
   ObjRange* range = AS_RANGE(args[0]);
-  sprintf(buffer, "%.14g..%.14g", range->from, range->to);
+  sprintf(buffer, "%.14g%s%.14g", range->from,
+          range->isInclusive ? ".." : "...", range->to);
   RETURN_VAL(wrenNewString(vm, buffer, strlen(buffer)));
 }
 
@@ -811,6 +833,7 @@ void wrenInitializeCore(WrenVM* vm)
   NATIVE(vm->rangeClass, "to", range_to);
   NATIVE(vm->rangeClass, "min", range_min);
   NATIVE(vm->rangeClass, "max", range_max);
+  NATIVE(vm->rangeClass, "isInclusive", range_isInclusive);
   NATIVE(vm->rangeClass, "iterate ", range_iterate);
   NATIVE(vm->rangeClass, "iteratorValue ", range_iteratorValue);
   NATIVE(vm->rangeClass, "toString", range_toString);
diff --git a/src/wren_value.c b/src/wren_value.c
index 7c7ef545..74f29244 100644
--- a/src/wren_value.c
+++ b/src/wren_value.c
@@ -301,12 +301,13 @@ Value wrenListRemoveAt(WrenVM* vm, ObjList* list, int index)
   return removed;
 }
 
-Value wrenNewRange(WrenVM* vm, double from, double to)
+Value wrenNewRange(WrenVM* vm, double from, double to, bool isInclusive)
 {
   ObjRange* range = allocate(vm, sizeof(ObjRange) + 16);
   initObj(vm, &range->obj, OBJ_RANGE);
   range->from = from;
   range->to = to;
+  range->isInclusive = isInclusive;
 
   return OBJ_VAL(range);
 }
diff --git a/src/wren_value.h b/src/wren_value.h
index a9341010..4f8193c3 100644
--- a/src/wren_value.h
+++ b/src/wren_value.h
@@ -317,6 +317,9 @@ typedef struct
 
   // The end of the range. May be greater or less than [from].
   double to;
+
+  // True if [to] is included in the range.
+  bool isInclusive;
 } ObjRange;
 
 
@@ -560,7 +563,7 @@ void wrenListInsert(WrenVM* vm, ObjList* list, Value value, int index);
 Value wrenListRemoveAt(WrenVM* vm, ObjList* list, int index);
 
 // Creates a new range from [from] to [to].
-Value wrenNewRange(WrenVM* vm, double from, double to);
+Value wrenNewRange(WrenVM* vm, double from, double to, bool isInclusive);
 
 // Creates a new string object and copies [text] into it.
 Value wrenNewString(WrenVM* vm, const char* text, size_t length);
diff --git a/test/range/exclusive_range_wrong_rhs_type.wren b/test/range/exclusive_range_wrong_rhs_type.wren
new file mode 100644
index 00000000..40a14247
--- /dev/null
+++ b/test/range/exclusive_range_wrong_rhs_type.wren
@@ -0,0 +1 @@
+1..."s" // expect runtime error: Right hand side of range must be a number.
diff --git a/test/range/floating_point.wren b/test/range/floating_point.wren
new file mode 100644
index 00000000..71df3157
--- /dev/null
+++ b/test/range/floating_point.wren
@@ -0,0 +1,31 @@
+// Ordered range.
+IO.print((2..5).from) // expect: 2
+IO.print((3..3).from) // expect: 3
+IO.print((0..3).from) // expect: 0
+IO.print((-5..3).from) // expect: -5
+IO.print((-5..-2).from) // expect: -5
+
+// Backwards range.
+IO.print((5..2).from) // expect: 5
+IO.print((3..0).from) // expect: 3
+IO.print((3..-5).from) // expect: 3
+IO.print((-2..-5).from) // expect: -2
+
+// Exclusive ordered range.
+IO.print((2...5).from) // expect: 2
+IO.print((3...3).from) // expect: 3
+IO.print((0...3).from) // expect: 0
+IO.print((-5...3).from) // expect: -5
+IO.print((-5...-2).from) // expect: -5
+
+// Exclusive backwards range.
+IO.print((5...2).from) // expect: 5
+IO.print((3...0).from) // expect: 3
+IO.print((3...-5).from) // expect: 3
+IO.print((-2...-5).from) // expect: -2
+
+// TODO: Test toString.
+// TODO: Non-number RHS.
+// TODO: Non-integer RHS.
+// TODO: Range iteration.
+// TODO: Empty or negative ranges.
diff --git a/test/range/from.wren b/test/range/from.wren
index 71df3157..114ea1fb 100644
--- a/test/range/from.wren
+++ b/test/range/from.wren
@@ -23,9 +23,3 @@ IO.print((5...2).from) // expect: 5
 IO.print((3...0).from) // expect: 3
 IO.print((3...-5).from) // expect: 3
 IO.print((-2...-5).from) // expect: -2
-
-// TODO: Test toString.
-// TODO: Non-number RHS.
-// TODO: Non-integer RHS.
-// TODO: Range iteration.
-// TODO: Empty or negative ranges.
diff --git a/test/range/inclusive_range_wrong_rhs_type.wren b/test/range/inclusive_range_wrong_rhs_type.wren
new file mode 100644
index 00000000..ff831f4f
--- /dev/null
+++ b/test/range/inclusive_range_wrong_rhs_type.wren
@@ -0,0 +1 @@
+1.."s" // expect runtime error: Right hand side of range must be a number.
diff --git a/test/range/is_inclusive.wren b/test/range/is_inclusive.wren
new file mode 100644
index 00000000..8f881aef
--- /dev/null
+++ b/test/range/is_inclusive.wren
@@ -0,0 +1,5 @@
+IO.print((0..0).isInclusive) // expect: true
+IO.print((0...0).isInclusive) // expect: false
+
+IO.print((-1..1).isInclusive) // expect: true
+IO.print((-1...1).isInclusive) // expect: false
diff --git a/test/range/iterate.wren b/test/range/iterate.wren
index ab4dd82a..db4e949d 100644
--- a/test/range/iterate.wren
+++ b/test/range/iterate.wren
@@ -1,3 +1,4 @@
+// Inclusive.
 var range = 1..3
 IO.print(range.iterate(null)) // expect: 1
 IO.print(range.iterate(1)) // expect: 2
@@ -5,4 +6,30 @@ IO.print(range.iterate(2)) // expect: 3
 IO.print(range.iterate(3)) // expect: false
 IO.print(range.iterate(4)) // expect: false
 
-// TODO: Negative and empty ranges.
+// Exclusive
+range = 1...3
+IO.print(range.iterate(null)) // expect: 1
+IO.print(range.iterate(1)) // expect: 2
+IO.print(range.iterate(2)) // expect: false
+
+// Negative inclusive range.
+range = 3..1
+IO.print(range.iterate(null)) // expect: 3
+IO.print(range.iterate(3)) // expect: 2
+IO.print(range.iterate(2)) // expect: 1
+IO.print(range.iterate(1)) // expect: false
+
+// Negative exclusive range.
+range = 3...1
+IO.print(range.iterate(null)) // expect: 3
+IO.print(range.iterate(3)) // expect: 2
+IO.print(range.iterate(2)) // expect: false
+
+// Empty inclusive range.
+range = 1..1
+IO.print(range.iterate(null)) // expect: 1
+IO.print(range.iterate(1)) // expect: false
+
+// Empty exclusive range.
+range = 1...1
+IO.print(range.iterate(null)) // expect: false
diff --git a/test/range/iterate_from_float.wren b/test/range/iterate_from_float.wren
new file mode 100644
index 00000000..23e7ca41
--- /dev/null
+++ b/test/range/iterate_from_float.wren
@@ -0,0 +1,18 @@
+// Starts at "from" and adds 1.0 each iteration.
+
+for (n in 1.3..4.5) IO.print(n)
+// expect: 1.3
+// expect: 2.3
+// expect: 3.3
+// expect: 4.3
+
+for (n in 1.3...4.5) IO.print(n)
+// expect: 1.3
+// expect: 2.3
+// expect: 3.3
+// expect: 4.3
+
+for (n in 1.3...4.3) IO.print(n)
+// expect: 1.3
+// expect: 2.3
+// expect: 3.3
diff --git a/test/range/max.wren b/test/range/max.wren
index 1cc27493..9c6672d2 100644
--- a/test/range/max.wren
+++ b/test/range/max.wren
@@ -12,11 +12,11 @@ IO.print((3..-5).max) // expect: 3
 IO.print((-2..-5).max) // expect: -2
 
 // Exclusive ordered range.
-IO.print((2...5).max) // expect: 4
+IO.print((2...5).max) // expect: 5
 IO.print((3...3).max) // expect: 3
-IO.print((0...3).max) // expect: 2
-IO.print((-5...3).max) // expect: 2
-IO.print((-5...-2).max) // expect: -3
+IO.print((0...3).max) // expect: 3
+IO.print((-5...3).max) // expect: 3
+IO.print((-5...-2).max) // expect: -2
 
 // Exclusive backwards range.
 IO.print((5...2).max) // expect: 5
diff --git a/test/range/min.wren b/test/range/min.wren
index baaba399..bcc019bf 100644
--- a/test/range/min.wren
+++ b/test/range/min.wren
@@ -13,14 +13,13 @@ IO.print((-2..-5).min) // expect: -5
 
 // Exclusive ordered range.
 IO.print((2...5).min) // expect: 2
-IO.print((3...3).min) // expect: 2
+IO.print((3...3).min) // expect: 3
 IO.print((0...3).min) // expect: 0
 IO.print((-5...3).min) // expect: -5
 IO.print((-5...-2).min) // expect: -5
 
 // Exclusive backwards range.
-// TODO: Is this what we want? "..." always means "subtract 1"?
-IO.print((5...2).min) // expect: 1
-IO.print((3...0).min) // expect: -1
-IO.print((3...-5).min) // expect: -6
-IO.print((-2...-5).min) // expect: -6
+IO.print((5...2).min) // expect: 2
+IO.print((3...0).min) // expect: 0
+IO.print((3...-5).min) // expect: -5
+IO.print((-2...-5).min) // expect: -5
diff --git a/test/range/to.wren b/test/range/to.wren
index cec8836a..ad3a5444 100644
--- a/test/range/to.wren
+++ b/test/range/to.wren
@@ -12,14 +12,14 @@ IO.print((3..-5).to) // expect: -5
 IO.print((-2..-5).to) // expect: -5
 
 // Exclusive ordered range.
-IO.print((2...5).to) // expect: 4
-IO.print((3...3).to) // expect: 2
-IO.print((0...3).to) // expect: 2
-IO.print((-5...3).to) // expect: 2
-IO.print((-5...-2).to) // expect: -3
+IO.print((2...5).to) // expect: 5
+IO.print((3...3).to) // expect: 3
+IO.print((0...3).to) // expect: 3
+IO.print((-5...3).to) // expect: 3
+IO.print((-5...-2).to) // expect: -2
 
 // Exclusive backwards range.
-IO.print((5...2).to) // expect: 1
-IO.print((3...0).to) // expect: -1
-IO.print((3...-5).to) // expect: -6
-IO.print((-2...-5).to) // expect: -6
+IO.print((5...2).to) // expect: 2
+IO.print((3...0).to) // expect: 0
+IO.print((3...-5).to) // expect: -5
+IO.print((-2...-5).to) // expect: -5
diff --git a/test/range/to_string.wren b/test/range/to_string.wren
new file mode 100644
index 00000000..795b0d3e
--- /dev/null
+++ b/test/range/to_string.wren
@@ -0,0 +1,7 @@
+IO.print(1..3) // expect: 1..3
+IO.print(12345.6789..12345.6789) // expect: 12345.6789..12345.6789
+IO.print(-100..-300) // expect: -100..-300
+
+IO.print(1...3) // expect: 1...3
+IO.print(12345.6789...12345.6789) // expect: 12345.6789...12345.6789
+IO.print(-100...-300) // expect: -100...-300