Make hstore_to_jsonb_loose match hstore_to_json_loose on what's a number.

Commit e09996ff8dee3f70 removed some ad-hoc code in hstore_to_json_loose
that determined whether an hstore value string looked like a number,
in favor of calling the JSON parser's is-it-a-number code.  However,
it neglected the fact that the exact same code appeared in
hstore_to_jsonb_loose.

This is not a bug, exactly, because the requirements on the two functions
are not the same: hstore_to_json_loose must accept only syntactically legal
JSON numbers as numbers, or it will produce invalid JSON output, as per bug
#12070 which spawned the prior commit.  But hstore_to_jsonb_loose could
accept anything that numeric_in will eat, other than Inf and NaN.

Nonetheless it seems surprising and arbitrary that the two functions don't
use the same rules for what is a number versus what is a string; especially
since they did use the same rules before the aforesaid commit.  For one
thing, that means that doing hstore_to_json_loose and then casting to jsonb
can produce results different from doing just hstore_to_jsonb_loose.

Hence, change hstore_to_jsonb_loose's logic to match hstore_to_json_loose,
ie, hstore values are treated as numbers when they match the JSON syntax
for numbers.

No back-patch, since this is more in the nature of a definitional change
than a bug fix.

diff --git a/contrib/hstore/hstore_io.c b/contrib/hstore/hstore_io.c
index aa7b7e1b3ef1c7f5c1974ab572146458593ff976..0c1d99a0150f656088e725bc44e905c5d6fa27b0 100644 (file)
--- a/contrib/hstore/hstore_io.c
+++ b/contrib/hstore/hstore_io.c
@@ -1387,7 +1387,6 @@ hstore_to_jsonb_loose(PG_FUNCTION_ARGS)
        JsonbParseState *state = NULL;
        JsonbValue *res;
        StringInfoData tmp;
-       bool            is_number;
 
        initStringInfo(&tmp);
 
@@ -1423,50 +1422,10 @@ hstore_to_jsonb_loose(PG_FUNCTION_ARGS)
                }
                else
                {
-                       is_number = false;
                        resetStringInfo(&tmp);
-
                        appendBinaryStringInfo(&tmp, HSTORE_VAL(entries, base, i),
                                                                   HSTORE_VALLEN(entries, i));
-
-                       /*
-                        * don't treat something with a leading zero followed by another
-                        * digit as numeric - could be a zip code or similar
-                        */
-                       if (tmp.len > 0 &&
-                               !(tmp.data[0] == '0' &&
-                                 isdigit((unsigned char) tmp.data[1])) &&
-                               strspn(tmp.data, "+-0123456789Ee.") == tmp.len)
-                       {
-                               /*
-                                * might be a number. See if we can input it as a numeric
-                                * value. Ignore any actual parsed value.
-                                */
-                               char       *endptr = "junk";
-                               long            lval;
-
-                               lval = strtol(tmp.data, &endptr, 10);
-                               (void) lval;
-                               if (*endptr == '\0')
-                               {
-                                       /*
-                                        * strol man page says this means the whole string is
-                                        * valid
-                                        */
-                                       is_number = true;
-                               }
-                               else
-                               {
-                                       /* not an int - try a double */
-                                       double          dval;
-
-                                       dval = strtod(tmp.data, &endptr);
-                                       (void) dval;
-                                       if (*endptr == '\0')
-                                               is_number = true;
-                               }
-                       }
-                       if (is_number)
+                       if (IsValidJsonNumber(tmp.data, tmp.len))
                        {
                                val.type = jbvNumeric;
                                val.val.numeric = DatumGetNumeric(