Minor improvements when talking about the type of a value.

assert-gooder.lua

@@ -280,11 +280,42 @@ local COMPLEX_TYPES = {
     ['function']    = true,
 }
 
+local function fmt_table_with_type (val)
+    assert(type(val) == 'table')
+
+    local subtype = 'table'
+
+    -- Find "last key"
+    do
+        local last_key, num_visited = nil, 0
+        repeat last_key, num_visited = next(val, last_key), num_visited + 1
+        until last_key == nil or type(last_key) ~= 'number' or last_key <= 0 or last_key > #val
+
+        -- Conclude:
+        if last_key == nil then
+            subtype = (num_visited == 1) and 'empty table' or 'sequence'
+        end
+    end
+
+    local addr  =  tostring(val):match '^table: (.*)$'
+    local attr  =  debug.getmetatable(val) ~= nil and ' with metatable' or ''
+
+    return ('%s%s: %s'):format(subtype, attr, addr)
+end
+
 local function fmt_val_with_type (val)
+
     -- Primitive values ARE their type, and don't need the annotation.
     if PRIMITIVE_VALUES[type(val)] then  return tostring(val)  end
+
+    -- Tables can be of many different styles
+    if type(val) == 'table' then
+        return fmt_table_with_type(val)
+    end
+
     -- Complex types are already formatted with some type information.
     if COMPLEX_TYPES[type(val)] then  return tostring(val)  end
+
     -- Numbers and string should have their types with them.
     return type(val) .. ' ' .. fmt_val(val)
 end

test/test_assert-gooder.lua

@@ -284,7 +284,7 @@ SUITE:addTest('Identify integer', function ()
 		local a = 5.21
         assert(a % 1 == 0)
 	end)
-	assert_equal('./test/test_assert-gooder.lua:'..curline(-2)..': '..'assertion failed! bad local \'a\' (integer expected, but got floating-point number 5.21)', msg)
+	assert_equal('./test/test_assert-gooder.lua:'..curline(-2)..': '..'assertion failed! bad local \'a\' (integer expected, but got decimal number 5.21)', msg)
 end)
 
 SUITE:addTest('Identify even number', function ()