From 3d6ea4b39785b91fb07a1aa02c9bb78e43e600f1 Mon Sep 17 00:00:00 2001
From: Nat Quayle Nelson <natquaylenelson@gmail.com>
Date: Mon, 1 Nov 2021 10:51:00 -0400
Subject: [PATCH] (or) should return the last value even if falsy

---
 kiss/src/kiss/Macros.hx                | 27 ++++++++++++++++----------
 kiss/src/test/cases/BasicTestCase.hx   |  2 +-
 kiss/src/test/cases/BasicTestCase.kiss |  8 +++++++-
 3 files changed, 25 insertions(+), 12 deletions(-)

diff --git a/kiss/src/kiss/Macros.hx b/kiss/src/kiss/Macros.hx
index 89d004ea..21955cfe 100644
--- a/kiss/src/kiss/Macros.hx
+++ b/kiss/src/kiss/Macros.hx
@@ -233,23 +233,30 @@ class Macros {
             var b = wholeExp.expBuilder();
 
             var uniqueVarSymbol = b.symbol();
+            var lastValue = args.pop();
 
             b.begin([
                 b.call(b.symbol("localVar"), [
                     b.meta("mut", b.typed("Dynamic", uniqueVarSymbol)),
                     b.symbol("null")
                 ]),
-                b.call(b.symbol("cond"), [
-                    for (arg in args) {
+                b.call(
+                    b.symbol("cond"), [
+                        for (arg in args) {
+                            b.call(
+                                b.call(b.symbol("set"), [
+                                    uniqueVarSymbol,
+                                    arg
+                                ]), [
+                                    uniqueVarSymbol
+                                ]);
+                        }
+                    ].concat([
                         b.call(
-                            b.call(b.symbol("set"), [
-                                uniqueVarSymbol,
-                                arg
-                            ]), [
-                                uniqueVarSymbol
-                            ]);
-                    }
-                ])
+                            b.symbol("true"), [
+                                lastValue
+                            ])
+                    ]))
             ]);
         };
 
diff --git a/kiss/src/test/cases/BasicTestCase.hx b/kiss/src/test/cases/BasicTestCase.hx
index 8bd50c54..462defb9 100644
--- a/kiss/src/test/cases/BasicTestCase.hx
+++ b/kiss/src/test/cases/BasicTestCase.hx
@@ -167,7 +167,7 @@ class BasicTestCase extends Test {
     }
 
     function testOr() {
-        Assert.equals(5, BasicTestCase.myOr1);
+        _testOr();
     }
 
     function testAnd() {
diff --git a/kiss/src/test/cases/BasicTestCase.kiss b/kiss/src/test/cases/BasicTestCase.kiss
index 6eda4ccd..946e0572 100644
--- a/kiss/src/test/cases/BasicTestCase.kiss
+++ b/kiss/src/test/cases/BasicTestCase.kiss
@@ -172,7 +172,13 @@
 (var myCondFallthrough (cond
     (false "not this")))
 
-(var myOr1 (or null 5))
+(function _testOr []
+    (Assert.equals 5 (or null 5))
+    // If the last value is falsy it can still be returned without breaking
+    // the expected behavior of or -- which also allows for the (or <optional arg> <default value>)
+    // idiom for empty arrays and strings
+    (Assert.equals (.toString []) (.toString (or null [])))
+    (Assert.equals "" (or null [] "")))
 
 (var myAnd1 (and 5 6))
 (var myAnd2 (and false 5 6))