From 70a1c4254230eb8f3c4d24ccbc253c0a28065d03 Mon Sep 17 00:00:00 2001
From: flywind <43030857+xflywind@users.noreply.github.com>
Date: Fri, 27 Nov 2020 03:30:19 +0800
Subject: [PATCH] add `**` to jsffi (#16141)

* fix rope index

* add testcase

* fix ropes format

* add `**` to jsffi

* add testcase

* changelog

Co-authored-by: Andreas Rumpf <rumpf_a@web.de>
---
 changelog.md        |  1 +
 lib/js/jsffi.nim    |  1 +
 tests/js/tjsffi.nim | 34 +++++++++++++++++++++++++++++++++-
 3 files changed, 35 insertions(+), 1 deletion(-)

diff --git a/changelog.md b/changelog.md
index bfbe59e1a..ba1bc9438 100644
--- a/changelog.md
+++ b/changelog.md
@@ -47,6 +47,7 @@
 - `repr` now doesn't insert trailing newline; previous behavior was very inconsistent,
   see #16034. Use `-d:nimLegacyReprWithNewline` for previous behavior.
 
+- Added `**` to jsffi.
 - `writeStackTrace` is available in JS backend now.
 
 ## Language changes
diff --git a/lib/js/jsffi.nim b/lib/js/jsffi.nim
index 0dce6f3b9..eedf45bb0 100644
--- a/lib/js/jsffi.nim
+++ b/lib/js/jsffi.nim
@@ -180,6 +180,7 @@ proc `>`  *(x, y: JsObject): JsObject {.importcpp: "(# > #)".}
 proc `<`  *(x, y: JsObject): JsObject {.importcpp: "(# < #)".}
 proc `>=` *(x, y: JsObject): JsObject {.importcpp: "(# >= #)".}
 proc `<=` *(x, y: JsObject): JsObject {.importcpp: "(# <= #)".}
+proc `**` *(x, y: JsObject): JsObject {.importcpp: "((#) ** #)".}
 proc `and`*(x, y: JsObject): JsObject {.importcpp: "(# && #)".}
 proc `or` *(x, y: JsObject): JsObject {.importcpp: "(# || #)".}
 proc `not`*(x:    JsObject): JsObject {.importcpp: "(!#)".}
diff --git a/tests/js/tjsffi.nim b/tests/js/tjsffi.nim
index af33cee8a..143ac4a25 100644
--- a/tests/js/tjsffi.nim
+++ b/tests/js/tjsffi.nim
@@ -323,7 +323,6 @@ block:
     console.log jsarguments[0]
 
 block:
-
   echo jsUndefined == jsNull
   echo jsUndefined == nil
   echo jsNull == nil
@@ -331,3 +330,36 @@ block:
   echo jsNull.isNil
   echo jsNull.isNull
   echo jsUndefined.isUndefined
+
+block: # test **
+  var a = toJs(0)
+  var b = toJs(0)
+  doAssert to(a ** b, int) == 1
+  a = toJs(1)
+  b = toJs(1)
+  doAssert to(a ** b, int) == 1
+  a = toJs(-1)
+  b = toJs(-1)
+  doAssert to(a ** b, int) == -1
+  a = toJs(6)
+  b = toJs(6)
+  doAssert to(a ** b, int) == 46656
+  a = toJs(5.5)
+  b = toJs(3)
+  doAssert to(a ** b, float) == 166.375
+  a = toJs(5)
+  b = toJs(3.0)
+  doAssert to(a ** b, float) == 125.0
+  a = toJs(7.0)
+  b = toJS(6.0)
+  doAssert to(a ** b, float) == 117649.0
+  a = toJs(8)
+  b = toJS(-2)
+  doAssert to(a ** b, float) == 0.015625
+
+  a = toJs(1)
+  b = toJs(1)
+  doAssert to(`**`(a + a, b), int) == 2
+
+  doAssert to(`**`(toJs(1) + toJs(1), toJs(2)), int) == 4
+