pgsql: pg_get_viewdef() and lateral references in COLUMNS of GRAPH_TABL

pg_get_viewdef() and lateral references in COLUMNS of GRAPH_TABLE

Expressions in GRAPH_TABLE COLUMNS list may have lateral references.
get_rule_expr() requires lateral namespaces to deparse such
references. get_from_clause_item() does not pass them when processing
the expressions in COLUMNS list causing ERROR "bogus varlevelsup: 0
offset 0". Fix get_from_clause_item() to pass input deparse_context
containing lateral namespaces to get_rule_expr() instead of the dummy
context.

Author: Satyanarayana Narlapuram <satyanarlapuram(at)gmail(dot)com>
Reviewed-by: Ashutosh Bapat <ashutosh(dot)bapat(dot)oss(at)gmail(dot)com>
Discussion: https://www.postgresql.org/message-id/flat/CAHg%2BQDcLVa2iBnggkHxY4itZbXtDMfsYHEjnCUYe9hNbnxDi-w%40mail.gmail.com

Branch
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master

Details
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https://git.postgresql.org/pg/commitdiff/9d2979dd6856e160f35544d79eb11f2c68c30985

Modified Files
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src/backend/utils/adt/ruleutils.c | 10 ++--------
src/test/regress/expected/graph_table.out | 26 ++++++++++++++++++--------
src/test/regress/sql/graph_table.sql | 12 ++++++++++--
3 files changed, 30 insertions(+), 18 deletions(-)