Added new match routine that works like a switch

moonpie/utility/match.lua

@@ -0,0 +1,17 @@
+-- Copyright (c) 2022 Trevor Redfern
+--
+-- This software is released under the MIT License.
+-- https://opensource.org/licenses/MIT
+
+return function(value, matchTable)
+  if matchTable[value] then
+    if type(matchTable[value]) == "function" then
+      return matchTable[value]()
+    end
+
+    return matchTable[value]
+  end
+
+  -- Return default
+  return matchTable._
+end

moonpie/utility/match_spec.lua

@@ -0,0 +1,38 @@
+-- Copyright (c) 2022 Trevor Redfern
+--
+-- This software is released under the MIT License.
+-- https://opensource.org/licenses/MIT
+
+describe("moonpie.utility.match", function()
+  local match = require "moonpie.utility.match"
+
+  it("takes a value and returns the matching value from the table", function()
+    local value = "B"
+    local out = match(value, {
+      A = 1,
+      B = 2,
+      C = 3,
+    })
+
+    assert.equals(2, out)
+  end)
+
+  it("if the matching value is a function it returns the result from the function", function()
+    local value = "C"
+    local out = match(value, {
+      A = function() return 1 end,
+      B = function() return 2 end,
+      C = function() return 3 end,
+    })
+
+    assert.equals(3, out)
+  end)
+
+  it("can have a default result if nothing matches", function()
+    local out = match("D", {
+      A = 1, B = 2, C = 3, _ = 10
+    })
+
+    assert.equals(10, out)
+  end)
+end)