Improve error messages for malformed array input strings.

Make the error messages issued by array_in() uniformly follow the style
	ERROR: malformed array literal: "actual input string"
	DETAIL: specific complaint here
and rewrite many of the specific complaints to be clearer.

The immediate motivation for doing this is a complaint from Josh Berkus
that json_to_record() produced an unintelligible error message when
dealing with an array item, because it tries to feed the JSON-format
array value to array_in().  Really it ought to be smart enough to
perform JSON-to-Postgres array conversion, but that's a future feature
not a bug fix.  In the meantime, this change is something we agreed
we could back-patch into 9.4, and it should help de-confuse things a bit.

diff --git a/src/backend/utils/adt/arrayfuncs.c b/src/backend/utils/adt/arrayfuncs.c
index 743351b95e0abc2a570be15982ef34e3f1730a35..933c6b035c60beb17a754e2edfcab25ffc2b7c9f 100644 (file)
--- a/src/backend/utils/adt/arrayfuncs.c
+++ b/src/backend/utils/adt/arrayfuncs.c
@@ -247,11 +247,13 @@ array_in(PG_FUNCTION_ARGS)
                     errmsg("number of array dimensions (%d) exceeds the maximum allowed (%d)",
                            ndim + 1, MAXDIM)));
 
-       for (q = p; isdigit((unsigned char) *q) || (*q == '-') || (*q == '+'); q++);
+       for (q = p; isdigit((unsigned char) *q) || (*q == '-') || (*q == '+'); q++)
+            /* skip */ ;
        if (q == p)             /* no digits? */
            ereport(ERROR,
                    (errcode(ERRCODE_INVALID_TEXT_REPRESENTATION),
-                    errmsg("missing dimension value")));
+                    errmsg("malformed array literal: \"%s\"", string),
+                    errdetail("\"[\" must introduce explicitly-specified array dimensions.")));
 
        if (*q == ':')
        {
@@ -259,11 +261,13 @@ array_in(PG_FUNCTION_ARGS)
            *q = '\0';
            lBound[ndim] = atoi(p);
            p = q + 1;
-           for (q = p; isdigit((unsigned char) *q) || (*q == '-') || (*q == '+'); q++);
+           for (q = p; isdigit((unsigned char) *q) || (*q == '-') || (*q == '+'); q++)
+                /* skip */ ;
            if (q == p)         /* no digits? */
                ereport(ERROR,
                        (errcode(ERRCODE_INVALID_TEXT_REPRESENTATION),
-                        errmsg("missing dimension value")));
+                        errmsg("malformed array literal: \"%s\"", string),
+                        errdetail("Missing array dimension value.")));
        }
        else
        {
@@ -273,7 +277,9 @@ array_in(PG_FUNCTION_ARGS)
        if (*q != ']')
            ereport(ERROR,
                    (errcode(ERRCODE_INVALID_TEXT_REPRESENTATION),
-                    errmsg("missing \"]\" in array dimensions")));
+                    errmsg("malformed array literal: \"%s\"", string),
+                    errdetail("Missing \"%s\" after array dimensions.",
+                              "]")));
 
        *q = '\0';
        ub = atoi(p);
@@ -293,7 +299,8 @@ array_in(PG_FUNCTION_ARGS)
        if (*p != '{')
            ereport(ERROR,
                    (errcode(ERRCODE_INVALID_TEXT_REPRESENTATION),
-                    errmsg("array value must start with \"{\" or dimension information")));
+                    errmsg("malformed array literal: \"%s\"", string),
+                    errdetail("Array value must start with \"{\" or dimension information.")));
        ndim = ArrayCount(p, dim, typdelim);
        for (i = 0; i < ndim; i++)
            lBound[i] = 1;
@@ -307,7 +314,9 @@ array_in(PG_FUNCTION_ARGS)
        if (strncmp(p, ASSGN, strlen(ASSGN)) != 0)
            ereport(ERROR,
                    (errcode(ERRCODE_INVALID_TEXT_REPRESENTATION),
-                    errmsg("missing assignment operator")));
+                    errmsg("malformed array literal: \"%s\"", string),
+                    errdetail("Missing \"%s\" after array dimensions.",
+                              ASSGN)));
        p += strlen(ASSGN);
        while (array_isspace(*p))
            p++;
@@ -319,18 +328,21 @@ array_in(PG_FUNCTION_ARGS)
        if (*p != '{')
            ereport(ERROR,
                    (errcode(ERRCODE_INVALID_TEXT_REPRESENTATION),
-                    errmsg("array value must start with \"{\" or dimension information")));
+                    errmsg("malformed array literal: \"%s\"", string),
+                    errdetail("Array contents must start with \"{\".")));
        ndim_braces = ArrayCount(p, dim_braces, typdelim);
        if (ndim_braces != ndim)
            ereport(ERROR,
                    (errcode(ERRCODE_INVALID_TEXT_REPRESENTATION),
-               errmsg("array dimensions incompatible with array literal")));
+                    errmsg("malformed array literal: \"%s\"", string),
+                    errdetail("Specified array dimensions do not match array contents.")));
        for (i = 0; i < ndim; ++i)
        {
            if (dim[i] != dim_braces[i])
                ereport(ERROR,
                        (errcode(ERRCODE_INVALID_TEXT_REPRESENTATION),
-               errmsg("array dimensions incompatible with array literal")));
+                        errmsg("malformed array literal: \"%s\"", string),
+                        errdetail("Specified array dimensions do not match array contents.")));
        }
    }
 
@@ -460,7 +472,8 @@ ArrayCount(const char *str, int *dim, char typdelim)
                    /* Signal a premature end of the string */
                    ereport(ERROR,
                            (errcode(ERRCODE_INVALID_TEXT_REPRESENTATION),
-                            errmsg("malformed array literal: \"%s\"", str)));
+                            errmsg("malformed array literal: \"%s\"", str),
+                            errdetail("Unexpected end of input.")));
                    break;
                case '\\':
 
@@ -475,7 +488,9 @@ ArrayCount(const char *str, int *dim, char typdelim)
                        parse_state != ARRAY_ELEM_DELIMITED)
                        ereport(ERROR,
                                (errcode(ERRCODE_INVALID_TEXT_REPRESENTATION),
-                           errmsg("malformed array literal: \"%s\"", str)));
+                             errmsg("malformed array literal: \"%s\"", str),
+                                errdetail("Unexpected \"%c\" character.",
+                                          '\\')));
                    if (parse_state != ARRAY_QUOTED_ELEM_STARTED)
                        parse_state = ARRAY_ELEM_STARTED;
                    /* skip the escaped character */
@@ -484,7 +499,8 @@ ArrayCount(const char *str, int *dim, char typdelim)
                    else
                        ereport(ERROR,
                                (errcode(ERRCODE_INVALID_TEXT_REPRESENTATION),
-                           errmsg("malformed array literal: \"%s\"", str)));
+                             errmsg("malformed array literal: \"%s\"", str),
+                                errdetail("Unexpected end of input.")));
                    break;
                case '\"':
 
@@ -498,7 +514,8 @@ ArrayCount(const char *str, int *dim, char typdelim)
                        parse_state != ARRAY_ELEM_DELIMITED)
                        ereport(ERROR,
                                (errcode(ERRCODE_INVALID_TEXT_REPRESENTATION),
-                           errmsg("malformed array literal: \"%s\"", str)));
+                             errmsg("malformed array literal: \"%s\"", str),
+                                errdetail("Unexpected array element.")));
                    in_quotes = !in_quotes;
                    if (in_quotes)
                        parse_state = ARRAY_QUOTED_ELEM_STARTED;
@@ -518,7 +535,9 @@ ArrayCount(const char *str, int *dim, char typdelim)
                            parse_state != ARRAY_LEVEL_DELIMITED)
                            ereport(ERROR,
                               (errcode(ERRCODE_INVALID_TEXT_REPRESENTATION),
-                           errmsg("malformed array literal: \"%s\"", str)));
+                             errmsg("malformed array literal: \"%s\"", str),
+                               errdetail("Unexpected \"%c\" character.",
+                                         '{')));
                        parse_state = ARRAY_LEVEL_STARTED;
                        if (nest_level >= MAXDIM)
                            ereport(ERROR,
@@ -546,21 +565,25 @@ ArrayCount(const char *str, int *dim, char typdelim)
                            !(nest_level == 1 && parse_state == ARRAY_LEVEL_STARTED))
                            ereport(ERROR,
                               (errcode(ERRCODE_INVALID_TEXT_REPRESENTATION),
-                           errmsg("malformed array literal: \"%s\"", str)));
+                             errmsg("malformed array literal: \"%s\"", str),
+                               errdetail("Unexpected \"%c\" character.",
+                                         '}')));
                        parse_state = ARRAY_LEVEL_COMPLETED;
                        if (nest_level == 0)
                            ereport(ERROR,
                               (errcode(ERRCODE_INVALID_TEXT_REPRESENTATION),
-                           errmsg("malformed array literal: \"%s\"", str)));
+                             errmsg("malformed array literal: \"%s\"", str),
+                            errdetail("Unmatched \"%c\" character.", '}')));
                        nest_level--;
 
                        if (nelems_last[nest_level] != 0 &&
                            nelems[nest_level] != nelems_last[nest_level])
                            ereport(ERROR,
                               (errcode(ERRCODE_INVALID_TEXT_REPRESENTATION),
-                               errmsg("multidimensional arrays must have "
-                                      "array expressions with matching "
-                                      "dimensions")));
+                             errmsg("malformed array literal: \"%s\"", str),
+                               errdetail("Multidimensional arrays must have "
+                                         "sub-arrays with matching "
+                                         "dimensions.")));
                        nelems_last[nest_level] = nelems[nest_level];
                        nelems[nest_level] = 1;
                        if (nest_level == 0)
@@ -591,7 +614,9 @@ ArrayCount(const char *str, int *dim, char typdelim)
                                parse_state != ARRAY_LEVEL_COMPLETED)
                                ereport(ERROR,
                                (errcode(ERRCODE_INVALID_TEXT_REPRESENTATION),
-                                errmsg("malformed array literal: \"%s\"", str)));
+                                errmsg("malformed array literal: \"%s\"", str),
+                                errdetail("Unexpected \"%c\" character.",
+                                          typdelim)));
                            if (parse_state == ARRAY_LEVEL_COMPLETED)
                                parse_state = ARRAY_LEVEL_DELIMITED;
                            else
@@ -612,7 +637,8 @@ ArrayCount(const char *str, int *dim, char typdelim)
                                parse_state != ARRAY_ELEM_DELIMITED)
                                ereport(ERROR,
                                (errcode(ERRCODE_INVALID_TEXT_REPRESENTATION),
-                                errmsg("malformed array literal: \"%s\"", str)));
+                                errmsg("malformed array literal: \"%s\"", str),
+                                errdetail("Unexpected array element.")));
                            parse_state = ARRAY_ELEM_STARTED;
                        }
                    }
@@ -631,7 +657,8 @@ ArrayCount(const char *str, int *dim, char typdelim)
        if (!array_isspace(*ptr++))
            ereport(ERROR,
                    (errcode(ERRCODE_INVALID_TEXT_REPRESENTATION),
-                    errmsg("malformed array literal: \"%s\"", str)));
+                    errmsg("malformed array literal: \"%s\"", str),
+                    errdetail("Junk after closing right brace.")));
    }
 
    /* special case for an empty array */
@@ -718,7 +745,8 @@ ReadArrayStr(char *arrayStr,
     * character.
     *
     * The error checking in this routine is mostly pro-forma, since we expect
-    * that ArrayCount() already validated the string.
+    * that ArrayCount() already validated the string.  So we don't bother
+    * with errdetail messages.
     */
    srcptr = arrayStr;
    while (!eoArray)

diff --git a/src/pl/plperl/expected/plperl_array.out b/src/pl/plperl/expected/plperl_array.out
index d21c84bd98a3d4ddea10d3ae2e8173ebbd33a2cc..6347b5211d27f8cedbec5b8cfc59be6c30eedcca 100644 (file)
--- a/src/pl/plperl/expected/plperl_array.out
+++ b/src/pl/plperl/expected/plperl_array.out
@@ -65,9 +65,10 @@ ERROR:  number of array dimensions (7) exceeds the maximum allowed (6)
 LINE 1: select plperl_sum_array('{{{{{{{1,2},{3,4}},{{5,6},{7,8}}},{...
                                 ^
 select plperl_sum_array('{{{1,2,3}, {4,5,6,7}}, {{7,8,9}, {10, 11, 12}}}');
-ERROR:  multidimensional arrays must have array expressions with matching dimensions
+ERROR:  malformed array literal: "{{{1,2,3}, {4,5,6,7}}, {{7,8,9}, {10, 11, 12}}}"
 LINE 1: select plperl_sum_array('{{{1,2,3}, {4,5,6,7}}, {{7,8,9}, {1...
                                 ^
+DETAIL:  Multidimensional arrays must have sub-arrays with matching dimensions.
 CREATE OR REPLACE FUNCTION plperl_concat(TEXT[]) RETURNS TEXT AS $$
    my $array_arg = shift;
    my $result = "";

diff --git a/src/test/regress/expected/arrays.out b/src/test/regress/expected/arrays.out
index cb606afd9cfe47b14dba1ae5011d1f806686252e..d33c9b90fffb22d1703a4e263b15f2d3aebdf4bb 100644 (file)
--- a/src/test/regress/expected/arrays.out
+++ b/src/test/regress/expected/arrays.out
@@ -1065,26 +1065,32 @@ select '{{1,{2}},{2,3}}'::text[];
 ERROR:  malformed array literal: "{{1,{2}},{2,3}}"
 LINE 1: select '{{1,{2}},{2,3}}'::text[];
                ^
+DETAIL:  Unexpected "{" character.
 select '{{},{}}'::text[];
 ERROR:  malformed array literal: "{{},{}}"
 LINE 1: select '{{},{}}'::text[];
                ^
+DETAIL:  Unexpected "}" character.
 select E'{{1,2},\\{2,3}}'::text[];
 ERROR:  malformed array literal: "{{1,2},\{2,3}}"
 LINE 1: select E'{{1,2},\\{2,3}}'::text[];
                ^
+DETAIL:  Unexpected "\" character.
 select '{{"1 2" x},{3}}'::text[];
 ERROR:  malformed array literal: "{{"1 2" x},{3}}"
 LINE 1: select '{{"1 2" x},{3}}'::text[];
                ^
+DETAIL:  Unexpected array element.
 select '{}}'::text[];
 ERROR:  malformed array literal: "{}}"
 LINE 1: select '{}}'::text[];
                ^
+DETAIL:  Junk after closing right brace.
 select '{ }}'::text[];
 ERROR:  malformed array literal: "{ }}"
 LINE 1: select '{ }}'::text[];
                ^
+DETAIL:  Junk after closing right brace.
 select array[];
 ERROR:  cannot determine type of empty array
 LINE 1: select array[];