util.format: ALL THE TESTS!!!

The more tests I made, the more Lua 5.1 quirks I discovered.

Tests generated using a tool plus some touch-up.

1 files changed, 49 insertions, 0 deletions

diff --git a/tools/generate_format_spec.lua b/tools/generate_format_spec.lua
new file mode 100644
index 00000000..66b68079
--- /dev/null
+++ b/tools/generate_format_spec.lua
@@ -0,0 +1,49 @@
+local format = require"util.format".format;
+local dump = require "util.serialization".new("oneline")
+local types = {
+	"nil";
+	"boolean";
+	"number";
+	"string";
+	"function";
+	-- "userdata";
+	"thread";
+	"table";
+};
+local example_values = {
+	["nil"] = { n = 1; nil };
+	["boolean"] = { true; false };
+	["number"] = { 97, -12345, 1.5; 73786976294838206464, math.huge, 2147483647 };
+	["string"] = { "hello", "foo \1\2\3 bar", "nödåtgärd", string.sub("nödåtgärd", 1, -4) };
+	["function"] = { function() end };
+	-- ["userdata"] = {};
+	["thread"] = { coroutine.create(function() end) };
+	["table"] = { {} };
+};
+local example_strings = setmetatable({
+	["nil"] = { "nil" };
+	["function"] = { "function() end" };
+	["number"] = { "97", "-12345", "1.5"; "73786976294838206464", "math.huge", "2147483647" };
+	["thread"] = { "coroutine.create(function() end)" };
+}, { __index = function() return {} end });
+for _, lua_type in ipairs(types) do
+	print(string.format("\t\tdescribe(\"%s\", function ()", lua_type));
+	local examples = example_values[lua_type];
+	for fmt in ("cdiouxXaAeEfgGqs"):gmatch(".") do
+		print(string.format("\t\t\tdescribe(\"to %%%s\", function ()", fmt));
+		print("\t\t\t\tit(\"works\", function ()");
+		for i=1, examples.n or #examples do
+			local example = examples[i];
+			if not tostring(example):match("%w+: 0[xX]%x+") then
+				print(string.format("\t\t\t\t\tassert.equal(%q, format(%q, %s))", format("%"..fmt, example), "%" .. fmt, example_strings[lua_type][i] or dump(example)));
+			else
+				print(string.format("\t\t\t\t\tassert.matches(\"[%s: 0[xX]%%x+]\", format(%q, %s))", lua_type, "%" .. fmt, example_strings[lua_type][i] or dump(example)));
+			end
+		end
+		print("\t\t\t\tend);");
+		print("\t\t\tend);");
+		print()
+	end
+	print("\t\tend);");
+	print()
+end