Expand parser and Unicode test coverage

test/testdata/invalid

@@ -77,6 +77,11 @@ unexpected token near end of file
 1
 unexpected newline near '"a'
 ========
+{"a":"a" 123}
+====
+1
+'}' expected near '123'
+========
 {[
 ====
 1
@@ -132,6 +137,16 @@ invalid token near '0'
 1
 invalid token near '-0'
 ========
+[troo
+====
+1
+invalid token near 'troo'
+========
+["\a <-- invalid escape"]
+====
+1
+invalid escape near '"\'
+========
 ["	 <-- tab character"]
 ====
 1
@@ -156,3 +171,8 @@ invalid Unicode '\uD888\u3210'
 ====
 1
 invalid Unicode '\uDFAA'
+========
+å
+====
+1
+'[' or '{' expected near 'å'

test/testdata/invalid-unicode

@@ -0,0 +1,89 @@
+<EFBFBD>
+====
+-1
+unable to decode byte 0xe5 at position 0
+========
+["<22> <-- invalid UTF-8"]
+====
+-1
+unable to decode byte 0xe5 at position 2
+========
+[<5B>]
+====
+-1
+unable to decode byte 0xe5 at position 1
+========
+[a<>]
+====
+-1
+unable to decode byte 0xe5 at position 2
+========
+["\u<>"]
+====
+-1
+unable to decode byte 0xe5 at position 4
+========
+["\<5C>"]
+====
+-1
+unable to decode byte 0xe5 at position 3
+========
+[0<>]
+====
+-1
+unable to decode byte 0xe5 at position 2
+========
+[123<32>]
+====
+-1
+unable to decode byte 0xe5 at position 4
+========
+[1e<31>]
+====
+-1
+unable to decode byte 0xe5 at position 3
+========
+[1e1<65>]
+====
+-1
+unable to decode byte 0xe5 at position 4
+========
+["<22>"]
+====
+-1
+unable to decode byte 0x81 at position 2
+========
+["<22>"]
+====
+-1
+unable to decode byte 0xc1 at position 2
+========
+["<22>"]
+====
+-1
+unable to decode byte 0xfd at position 2
+========
+["<22><><EFBFBD><EFBFBD>"]
+====
+-1
+unable to decode byte 0xf4 at position 2
+========
+["<22><><EFBFBD> <-- overlong encoding"]
+====
+-1
+unable to decode byte 0xe0 at position 2
+========
+["<22><><EFBFBD><EFBFBD> <-- overlong encoding"]
+====
+-1
+unable to decode byte 0xf0 at position 2
+========
+["<22><> <-- truncated UTF-8"]
+====
+-1
+unable to decode byte 0xe0 at position 2
+========
+["<22><><EFBFBD> <-- encoded surrogate half"]
+====
+-1
+unable to decode byte 0xed at position 2

test/testdata/valid

@@ -4,7 +4,7 @@
 ========
 ["abcdefghijklmnopqrstuvwxyz1234567890 "]
 ========
-["€þıœəßð some utf-8 ĸʒ×ŋµåäö"]
+["€þıœəßð some utf-8 ĸʒ×ŋµåäö𝄞"]
 ========
 ["\"\\\/\b\f\n\r\t"]
 ========