Support parsing raw literals in UniValue

Fixes following test failures in https://github.com/nst/JSONTestSuite:

bitcoin SHOULD_HAVE_PASSED  y_structure_lonely_negative_real.json
bitcoin SHOULD_HAVE_PASSED  y_structure_lonely_string.json
bitcoin SHOULD_HAVE_PASSED  y_structure_lonely_false.json
bitcoin SHOULD_HAVE_PASSED  y_structure_lonely_null.json
bitcoin SHOULD_HAVE_PASSED  y_string_space.json
bitcoin SHOULD_HAVE_PASSED  y_structure_string_empty.json
bitcoin SHOULD_HAVE_PASSED  y_structure_lonely_int.json
bitcoin SHOULD_HAVE_PASSED  y_structure_lonely_true.json

Makefile.am

@@ -88,6 +88,11 @@ TEST_FILES = \
 	$(TEST_DATA_DIR)/pass2.json \
 	$(TEST_DATA_DIR)/pass3.json \
 	$(TEST_DATA_DIR)/round1.json \
-	$(TEST_DATA_DIR)/round2.json
+	$(TEST_DATA_DIR)/round2.json \
+	$(TEST_DATA_DIR)/round3.json \
+	$(TEST_DATA_DIR)/round4.json \
+	$(TEST_DATA_DIR)/round5.json \
+	$(TEST_DATA_DIR)/round6.json \
+	$(TEST_DATA_DIR)/round7.json
 
 EXTRA_DIST=$(TEST_FILES) $(GEN_SRCS)

lib/univalue_read.cpp

@@ -177,7 +177,7 @@ enum jtokentype getJsonToken(string& tokenVal, unsigned int& consumed,
         string valStr;
         JSONUTF8StringFilter writer(valStr);
 
-        while (*raw) {
+        while (true) {
             if ((unsigned char)*raw < 0x20)
                 return JTOK_ERR;
 
@@ -371,9 +371,6 @@ bool UniValue::read(const char *raw)
         case JTOK_KW_NULL:
         case JTOK_KW_TRUE:
         case JTOK_KW_FALSE: {
-            if (!stack.size())
-                return false;
-
             UniValue tmpVal;
             switch (tok) {
             case JTOK_KW_NULL:
@@ -388,6 +385,11 @@ bool UniValue::read(const char *raw)
             default: /* impossible */ break;
             }
 
+            if (!stack.size()) {
+                *this = tmpVal;
+                break;
+            }
+
             UniValue *top = stack.back();
             top->values.push_back(tmpVal);
 
@@ -396,10 +398,12 @@ bool UniValue::read(const char *raw)
             }
 
         case JTOK_NUMBER: {
-            if (!stack.size())
-                return false;
-
             UniValue tmpVal(VNUM, tokenVal);
+            if (!stack.size()) {
+                *this = tmpVal;
+                break;
+            }
+
             UniValue *top = stack.back();
             top->values.push_back(tmpVal);
 
@@ -408,17 +412,18 @@ bool UniValue::read(const char *raw)
             }
 
         case JTOK_STRING: {
-            if (!stack.size())
-                return false;
-
-            UniValue *top = stack.back();
-
             if (expect(OBJ_NAME)) {
+                UniValue *top = stack.back();
                 top->keys.push_back(tokenVal);
                 clearExpect(OBJ_NAME);
                 setExpect(COLON);
             } else {
                 UniValue tmpVal(VSTR, tokenVal);
+                if (!stack.size()) {
+                    *this = tmpVal;
+                    break;
+                }
+                UniValue *top = stack.back();
                 top->values.push_back(tmpVal);
             }
 

test/fail1.json

@@ -1 +1 @@
-"A JSON payload should be an object or array, not a string."
+"This is a string that never ends, yes it goes on and on, my friends.

test/round3.json

@@ -0,0 +1 @@
+"abcdefghijklmnopqrstuvwxyz"

test/round4.json

@@ -0,0 +1 @@
+7

test/round5.json

@@ -0,0 +1 @@
+true

test/round6.json

@@ -0,0 +1 @@
+false

test/round7.json

@@ -0,0 +1 @@
+null

test/unitester.cpp

@@ -125,6 +125,11 @@ static const char *filenames[] = {
         "pass3.json",
         "round1.json",              // round-trip test
         "round2.json",              // unicode
+        "round3.json",              // bare string
+        "round4.json",              // bare number
+        "round5.json",              // bare true
+        "round6.json",              // bare false
+        "round7.json",              // bare null
 };
 
 // Test \u handling