Make array_to_tsvector() sort and de-duplicate the given strings.

This is required for the result to be a legal tsvector value.
Noted while fooling with Andreas Seltenreich's ts_delete() crash.

Discussion: <87invhoj6e.fsf@credativ.de>

diff --git a/doc/src/sgml/func.sgml b/doc/src/sgml/func.sgml
index 971e642276c4ac4835e0b2d9cbf8a700d292d7fa..783033403a436eb70fd7016aac71cf33055bb625 100644 (file)
--- a/doc/src/sgml/func.sgml
+++ b/doc/src/sgml/func.sgml
@@ -9294,7 +9294,7 @@ CREATE TYPE rainbow AS ENUM ('red', 'orange', 'yellow', 'green', 'blue', 'purple
         <entry><type>tsvector</type></entry>
         <entry>convert array of lexemes to <type>tsvector</type></entry>
         <entry><literal>array_to_tsvector('{fat,cat,rat}'::text[])</literal></entry>
-        <entry><literal>'fat' 'cat' 'rat'</literal></entry>
+        <entry><literal>'cat' 'fat' 'rat'</literal></entry>
        </row>
        <row>
         <entry>

diff --git a/src/backend/utils/adt/tsvector_op.c b/src/backend/utils/adt/tsvector_op.c
index 29cc687643c1746d5a8b270ee1cbaa3ca548ae67..ad5a254c57e385c86d8d8cda223f971c253399f0 100644 (file)
--- a/src/backend/utils/adt/tsvector_op.c
+++ b/src/backend/utils/adt/tsvector_op.c
@@ -416,17 +416,34 @@ tsvector_bsearch(const TSVector tsv, char *lexeme, int lexeme_len)
        return -1;
 }
 
+/*
+ * qsort comparator functions
+ */
+
 static int
-compareint(const void *va, const void *vb)
+compare_int(const void *va, const void *vb)
 {
-       int32           a = *((const int32 *) va);
-       int32           b = *((const int32 *) vb);
+       int                     a = *((const int *) va);
+       int                     b = *((const int *) vb);
 
        if (a == b)
                return 0;
        return (a > b) ? 1 : -1;
 }
 
+static int
+compare_text_lexemes(const void *va, const void *vb)
+{
+       Datum           a = *((const Datum *) va);
+       Datum           b = *((const Datum *) vb);
+       char       *alex = VARDATA_ANY(a);
+       int                     alex_len = VARSIZE_ANY_EXHDR(a);
+       char       *blex = VARDATA_ANY(b);
+       int                     blex_len = VARSIZE_ANY_EXHDR(b);
+
+       return tsCompareString(alex, alex_len, blex, blex_len, false);
+}
+
 /*
  * Internal routine to delete lexemes from TSVector by array of offsets.
  *
@@ -459,7 +476,7 @@ tsvector_delete_by_indices(TSVector tsv, int *indices_to_delete,
        {
                int                     kp;
 
-               qsort(indices_to_delete, indices_count, sizeof(int), compareint);
+               qsort(indices_to_delete, indices_count, sizeof(int), compare_int);
                kp = 0;
                for (k = 1; k < indices_count; k++)
                {
@@ -743,32 +760,50 @@ array_to_tsvector(PG_FUNCTION_ARGS)
        bool       *nulls;
        int                     nitems,
                                i,
+                               j,
                                tslen,
                                datalen = 0;
        char       *cur;
 
        deconstruct_array(v, TEXTOID, -1, false, 'i', &dlexemes, &nulls, &nitems);
 
+       /* Reject nulls (maybe we should just ignore them, instead?) */
        for (i = 0; i < nitems; i++)
        {
                if (nulls[i])
                        ereport(ERROR,
                                        (errcode(ERRCODE_NULL_VALUE_NOT_ALLOWED),
                                         errmsg("lexeme array may not contain nulls")));
+       }
 
-               datalen += VARSIZE_ANY_EXHDR(dlexemes[i]);
+       /* Sort and de-dup, because this is required for a valid tsvector. */
+       if (nitems > 1)
+       {
+               qsort(dlexemes, nitems, sizeof(Datum), compare_text_lexemes);
+               j = 0;
+               for (i = 1; i < nitems; i++)
+               {
+                       if (compare_text_lexemes(&dlexemes[j], &dlexemes[i]) < 0)
+                               dlexemes[++j] = dlexemes[i];
+               }
+               nitems = ++j;
        }
 
+       /* Calculate space needed for surviving lexemes. */
+       for (i = 0; i < nitems; i++)
+               datalen += VARSIZE_ANY_EXHDR(dlexemes[i]);
        tslen = CALCDATASIZE(nitems, datalen);
+
+       /* Allocate and fill tsvector. */
        tsout = (TSVector) palloc0(tslen);
        SET_VARSIZE(tsout, tslen);
        tsout->size = nitems;
+
        arrout = ARRPTR(tsout);
        cur = STRPTR(tsout);
-
        for (i = 0; i < nitems; i++)
        {
-               char       *lex = VARDATA(dlexemes[i]);
+               char       *lex = VARDATA_ANY(dlexemes[i]);
                int                     lex_len = VARSIZE_ANY_EXHDR(dlexemes[i]);
 
                memcpy(cur, lex, lex_len);

diff --git a/src/test/regress/expected/tstypes.out b/src/test/regress/expected/tstypes.out
index 73f43c5ff027364d1b8ed7ad093245f2ba32147c..8d9290cbac122d00222c97304f2f6de3c42438b7 100644 (file)
--- a/src/test/regress/expected/tstypes.out
+++ b/src/test/regress/expected/tstypes.out
@@ -1165,6 +1165,13 @@ SELECT array_to_tsvector(ARRAY['base','hidden','rebel','spaceship','strike']);
 
 SELECT array_to_tsvector(ARRAY['base','hidden','rebel','spaceship', NULL]);
 ERROR:  lexeme array may not contain nulls
+-- array_to_tsvector must sort and de-dup
+SELECT array_to_tsvector(ARRAY['foo','bar','baz','bar']);
+ array_to_tsvector 
+-------------------
+ 'bar' 'baz' 'foo'
+(1 row)
+
 SELECT setweight('w:12B w:13* w:12,5,6 a:1,3* a:3 w asd:1dc asd zxc:81,567,222A'::tsvector, 'c');
                         setweight                         
 ----------------------------------------------------------

diff --git a/src/test/regress/sql/tstypes.sql b/src/test/regress/sql/tstypes.sql
index f0c06ba5f5a6e1c37ca51521bb5ad7690579da11..9ea93a2993845a71ee452e8a0e18674f7ea78b15 100644 (file)
--- a/src/test/regress/sql/tstypes.sql
+++ b/src/test/regress/sql/tstypes.sql
@@ -226,6 +226,8 @@ SELECT tsvector_to_array('base hidden rebel spaceship strike'::tsvector);
 
 SELECT array_to_tsvector(ARRAY['base','hidden','rebel','spaceship','strike']);
 SELECT array_to_tsvector(ARRAY['base','hidden','rebel','spaceship', NULL]);
+-- array_to_tsvector must sort and de-dup
+SELECT array_to_tsvector(ARRAY['foo','bar','baz','bar']);
 
 SELECT setweight('w:12B w:13* w:12,5,6 a:1,3* a:3 w asd:1dc asd zxc:81,567,222A'::tsvector, 'c');
 SELECT setweight('a:1,3A asd:1C w:5,6,12B,13A zxc:81,222A,567'::tsvector, 'c');