-- Strings.
SELECT '""'::json;				-- OK.
SELECT $$''$$::json;			-- ERROR, single quotes are not allowed
SELECT '"abc"'::json;			-- OK
SELECT '"abc'::json;			-- ERROR, quotes not closed
SELECT '"abc
def"'::json;					-- ERROR, unescaped newline in string constant
SELECT '"\n\"\\"'::json;		-- OK, legal escapes
SELECT '"\v"'::json;			-- ERROR, not a valid JSON escape
SELECT '"\u"'::json;			-- ERROR, incomplete escape
SELECT '"\u00"'::json;			-- ERROR, incomplete escape
SELECT '"\u000g"'::json;		-- ERROR, g is not a hex digit
SELECT '"\u0000"'::json;		-- OK, legal escape
SELECT '"\uaBcD"'::json;		-- OK, uppercase and lower case both OK

-- Numbers.
SELECT '1'::json;				-- OK
SELECT '0'::json;				-- OK
SELECT '01'::json;				-- ERROR, not valid according to JSON spec
SELECT '0.1'::json;				-- OK
SELECT '9223372036854775808'::json;	-- OK, even though it's too large for int8
SELECT '1e100'::json;			-- OK
SELECT '1.3e100'::json;			-- OK
SELECT '1f2'::json;				-- ERROR

-- Arrays.
SELECT '[]'::json;				-- OK
SELECT '[[[[[[[[[[[[[[[[[[[[[[[[[[[[[[[[[[[[[[[[[[[[[[[[[[[[[[[[[[[[[[[[[[[[[[[[[[[[[[[[[[[[[[[[[[[[[[[[[[[[]]]]]]]]]]]]]]]]]]]]]]]]]]]]]]]]]]]]]]]]]]]]]]]]]]]]]]]]]]]]]]]]]]]]]]]]]]]]]]]]]]]]]]]]]]]]]]]]]]]]'::json;  -- OK
SELECT '[1,2]'::json;			-- OK
SELECT '[1,2,]'::json;			-- ERROR, trailing comma
SELECT '[1,2'::json;			-- ERROR, no closing bracket
SELECT '[1,[2]'::json;			-- ERROR, no closing bracket

-- Objects.
SELECT '{}'::json;				-- OK
SELECT '{"abc"}'::json;			-- ERROR, no value
SELECT '{"abc":1}'::json;		-- OK
SELECT '{1:"abc"}'::json;		-- ERROR, keys must be strings
SELECT '{"abc",1}'::json;		-- ERROR, wrong separator
SELECT '{"abc"=1}'::json;		-- ERROR, totally wrong separator
SELECT '{"abc"::1}'::json;		-- ERROR, another wrong separator
SELECT '{"abc":1,"def":2,"ghi":[3,4],"hij":{"klm":5,"nop":[6]}}'::json; -- OK
SELECT '{"abc":1:2}'::json;		-- ERROR, colon in wrong spot
SELECT '{"abc":1,3}'::json;		-- ERROR, no value

-- Miscellaneous stuff.
SELECT 'true'::json;			-- OK
SELECT 'false'::json;			-- OK
SELECT 'null'::json;			-- OK
SELECT ' true '::json;			-- OK, even with extra whitespace
SELECT 'true false'::json;		-- ERROR, too many values
SELECT 'true, false'::json;		-- ERROR, too many values
SELECT 'truf'::json;			-- ERROR, not a keyword
SELECT 'trues'::json;			-- ERROR, not a keyword
SELECT ''::json;				-- ERROR, no value
SELECT '    '::json;			-- ERROR, no value