From faaff0d777d482f6378407289125c2bf32d7e1d9 Mon Sep 17 00:00:00 2001
From: Vincent Robinson <robinsonvincent89@gmail.com>
Date: Thu, 1 Apr 2021 15:18:58 -0700
Subject: [PATCH] Add `math.round` and fix `vector.round` (#10803)

---
 .luacheckrc                     | 82 +++++++++++++++++++++++++++++++++
 builtin/common/misc_helpers.lua |  9 ++++
 builtin/common/vector.lua       |  6 +--
 doc/lua_api.txt                 |  3 ++
 4 files changed, 97 insertions(+), 3 deletions(-)
 create mode 100644 .luacheckrc

diff --git a/.luacheckrc b/.luacheckrc
new file mode 100644
index 000000000..a922bdea9
--- /dev/null
+++ b/.luacheckrc
@@ -0,0 +1,82 @@
+unused_args = false
+allow_defined_top = true
+
+ignore = {
+	"131", -- Unused global variable
+	"431", -- Shadowing an upvalue
+	"432", -- Shadowing an upvalue argument
+}
+
+read_globals = {
+	"ItemStack",
+	"INIT",
+	"DIR_DELIM",
+	"dump", "dump2",
+	"fgettext", "fgettext_ne",
+	"vector",
+	"VoxelArea",
+	"profiler",
+	"Settings",
+
+	string = {fields = {"split", "trim"}},
+	table  = {fields = {"copy", "getn", "indexof", "insert_all"}},
+	math   = {fields = {"hypot", "round"}},
+}
+
+globals = {
+	"core",
+	"gamedata",
+	os = { fields = { "tempfolder" } },
+	"_",
+}
+
+files["builtin/client/register.lua"] = {
+	globals = {
+		debug = {fields={"getinfo"}},
+	}
+}
+
+files["builtin/common/misc_helpers.lua"] = {
+	globals = {
+		"dump", "dump2", "table", "math", "string",
+		"fgettext", "fgettext_ne", "basic_dump", "game", -- ???
+		"file_exists", "get_last_folder", "cleanup_path", -- ???
+	},
+}
+
+files["builtin/common/vector.lua"] = {
+	globals = { "vector" },
+}
+
+files["builtin/game/voxelarea.lua"] = {
+	globals = { "VoxelArea" },
+}
+
+files["builtin/game/init.lua"] = {
+	globals = { "profiler" },
+}
+
+files["builtin/common/filterlist.lua"] = {
+	globals = {
+		"filterlist",
+		"compare_worlds", "sort_worlds_alphabetic", "sort_mod_list", -- ???
+	},
+}
+
+files["builtin/mainmenu"] = {
+	globals = {
+		"gamedata",
+	},
+
+	read_globals = {
+		"PLATFORM",
+	},
+}
+
+files["builtin/common/tests"] = {
+	read_globals = {
+		"describe",
+		"it",
+		"assert",
+	},
+}
diff --git a/builtin/common/misc_helpers.lua b/builtin/common/misc_helpers.lua
index 232586327..b248a2294 100644
--- a/builtin/common/misc_helpers.lua
+++ b/builtin/common/misc_helpers.lua
@@ -295,6 +295,15 @@ function cleanup_path(temppath)
 	return temppath
 end
 
+
+function math.round(x)
+	if x >= 0 then
+		return math.floor(x + 0.5)
+	end
+	return math.ceil(x - 0.5)
+end
+
+
 function core.formspec_escape(text)
 	if text ~= nil then
 		text = string.gsub(text,"\\","\\\\")
diff --git a/builtin/common/vector.lua b/builtin/common/vector.lua
index d6437deda..b04c12610 100644
--- a/builtin/common/vector.lua
+++ b/builtin/common/vector.lua
@@ -41,9 +41,9 @@ end
 
 function vector.round(v)
 	return {
-		x = math.floor(v.x + 0.5),
-		y = math.floor(v.y + 0.5),
-		z = math.floor(v.z + 0.5)
+		x = math.round(v.x),
+		y = math.round(v.y),
+		z = math.round(v.z)
 	}
 end
 
diff --git a/doc/lua_api.txt b/doc/lua_api.txt
index 9479503d9..0d5fe5914 100644
--- a/doc/lua_api.txt
+++ b/doc/lua_api.txt
@@ -2392,6 +2392,7 @@ For the following functions, `v`, `v1`, `v2` are vectors,
     * Returns a vector, each dimension rounded down.
 * `vector.round(v)`:
     * Returns a vector, each dimension rounded to nearest integer.
+    * At a multiple of 0.5, rounds away from zero.
 * `vector.apply(v, func)`:
     * Returns a vector where the function `func` has been applied to each
       component.
@@ -2464,6 +2465,8 @@ Helper functions
     * If the absolute value of `x` is within the `tolerance` or `x` is NaN,
       `0` is returned.
 * `math.factorial(x)`: returns the factorial of `x`
+* `math.round(x)`: Returns `x` rounded to the nearest integer.
+    * At a multiple of 0.5, rounds away from zero.
 * `string.split(str, separator, include_empty, max_splits, sep_is_pattern)`
     * `separator`: string, default: `","`
     * `include_empty`: boolean, default: `false`