pgsql: Throw error in jsonb_path_match() when result is not single bool

Throw error in jsonb_path_match() when result is not single boolean

jsonb_path_match() checks if jsonb document matches jsonpath query. Therefore,
jsonpath query should return single boolean. Currently, if result of jsonpath
is not a single boolean, NULL is returned independently whether silent mode
is on or off. But that appears to be wrong when silent mode is off. This
commit makes jsonb_path_match() throw an error in this case.

Author: Nikita Glukhov

Branch
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master

Details
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https://git.postgresql.org/pg/commitdiff/b4cc19ab01ffe6a72a915b21aa41536de80923f5

Modified Files
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src/backend/utils/adt/jsonpath_exec.c | 26 +++++++++-----
src/test/regress/expected/jsonb_jsonpath.out | 51 ++++++++++++++++++++++++++++
src/test/regress/sql/jsonb_jsonpath.sql | 12 +++++++
3 files changed, 80 insertions(+), 9 deletions(-)