Lua API: Ensure unit test assertions specify a message string

wesnoth · Jul 28, 2021 · 18e4a64 · 18e4a64
1 parent dfb52a8
commit 18e4a64
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Showing 2 changed files with 40 additions and 15 deletions.
diff --git a/data/lua/core/unit_test.lua b/data/lua/core/unit_test.lua
@@ -43,6 +43,31 @@ if rawget(_G, 'unit_test') ~= nil then
 	function unit_test.log(prefix, message)
 		std_print(prefix .. ': ' .. message)
 	end
+
+	-- This is a way to ensure that all assertions contain a descriptive message
+	setmetatable(unit_test, {
+		__newindex = function(self, key, val)
+			std_print('adding unit_test.' .. key)
+			if string.sub(key, 1, 6) == 'assert' then
+				local info = debug.getinfo(val, 'u')
+				local recursion_guard = false
+				local underlying_fcn = val
+				local fcn = function(...)
+					if not recursion_guard then
+						-- Last argument is the message
+						local message = select(info.nparams, ...)
+						recursion_guard = true
+						std_print('verifying assert message', message)
+						unit_test.assert_not_equal(message, nil, string.format('unit_test.%s missing a message', key))
+						recursion_guard = false
+					end
+					underlying_fcn(...)
+				end
+				val = fcn
+			end
+			rawset(self, key, val)
+		end
+	})
 
 	--! Fail the test with a message unless the condition is true
 	function unit_test.assert(condition, message)

diff --git a/data/test/scenarios/as_text.cfg b/data/test/scenarios/as_text.cfg
@@ -26,26 +26,26 @@
 
         [lua]
             code = <<
-                unit_test.assert_equal(wesnoth.as_text("a"), '"a"')
-                unit_test.assert_equal(wesnoth.as_text(1), "1")
-                unit_test.assert_equal(wesnoth.as_text(true), "true")
-                unit_test.assert_equal(wesnoth.as_text({ "a", "b", "c" }), '{"1":"a","2":"b","3":"c"}')
+                unit_test.assert_equal(wesnoth.as_text("a"), '"a"', 'convert string to string')
+                unit_test.assert_equal(wesnoth.as_text(1), "1", 'convert number to string')
+                unit_test.assert_equal(wesnoth.as_text(true), "true", 'convert boolean to string')
+                unit_test.assert_equal(wesnoth.as_text({ "a", "b", "c" }), '{"1":"a","2":"b","3":"c"}', 'convert array to string')
 
                 -- associative table iteration order not defined and can vary between runs even when the data remains identical
                 local tab_txt = wesnoth.as_text({ a = 1, b = false, c = "d" })
-                unit_test.assert_contains(tab_txt, '"a":1')
-                unit_test.assert_contains(tab_txt, '"b":false')
-                unit_test.assert_contains(tab_txt, '"c":"d"')
+                unit_test.assert_contains(tab_txt, '"a":1', 'convert table to string: first key')
+                unit_test.assert_contains(tab_txt, '"b":false', 'convert table to string: second key')
+                unit_test.assert_contains(tab_txt, '"c":"d"', 'convert table to string: third key')
 
                 local wml_tab_txt = wesnoth.as_text(wml.variables["var"])
-                unit_test.assert_contains(wml_tab_txt, '{"1":{"1":"one","2":{"1":{"1":"first","2":{')
-                unit_test.assert_contains(wml_tab_txt, '"a":1')
-                unit_test.assert_contains(wml_tab_txt, '"b":5')
-                unit_test.assert_contains(wml_tab_txt, '"c":true')
-                unit_test.assert_contains(wml_tab_txt, ',"2":{"1":"two","2":{"1":{"1":"second","2":{')
-                unit_test.assert_contains(wml_tab_txt, '"x":9')
-                unit_test.assert_contains(wml_tab_txt, '"y":3')
-                unit_test.assert_contains(wml_tab_txt, '"z":false')
+                unit_test.assert_contains(wml_tab_txt, '{"1":{"1":"one","2":{"1":{"1":"first","2":{', 'convert wml table to string: first tag opener')
+                unit_test.assert_contains(wml_tab_txt, '"a":1', 'convert wml table to string: first tag first key')
+                unit_test.assert_contains(wml_tab_txt, '"b":5', 'convert wml table to string: first tag second key')
+                unit_test.assert_contains(wml_tab_txt, '"c":true', 'convert wml table to string: first tag third key')
+                unit_test.assert_contains(wml_tab_txt, ',"2":{"1":"two","2":{"1":{"1":"second","2":{', 'convert wml table to string: second tag opener')
+                unit_test.assert_contains(wml_tab_txt, '"x":9', 'convert wml table to string: second tag first key')
+                unit_test.assert_contains(wml_tab_txt, '"y":3', 'convert wml table to string: second tag second key')
+                unit_test.assert_contains(wml_tab_txt, '"z":false', 'convert wml table to string: second tag third key')
 
                 -- Pass the test. Doesn't do anything if any of the above assertions has failed.
                 unit_test.succeed()