lateral (clj)

(ns honey.sql.helpers-test
  (:refer-clojure :exclude [filter for group-by partition-by set update])
  (:require [clojure.test :refer [deftest is testing]]
            [honey.sql :as sql]
            [honey.sql.helpers :as h
             :refer [add-column add-index alter-table columns create-table create-table-as create-view
                     create-materialized-view drop-view drop-materialized-view
                     create-index
                     bulk-collect-into
                     cross-join do-update-set drop-column drop-index drop-table
                     filter from full-join
                     group-by having insert-into
                     join-by join lateral left-join limit offset on-conflict
                     on-duplicate-key-update
                     order-by over partition-by refresh-materialized-view
                     rename-column rename-table returning right-join
                     select select-distinct select-top select-distinct-top
                     values where window with with-columns
                     with-data within-group]]))

(deftest from-expression-tests
  (testing "FROM can be a function invocation"
    (is (= ["SELECT foo, bar FROM F(?) AS x" 1]
           (sql/format {:select [:foo :bar] :from [[[:f 1] :x]]}))))
  ;; these two examples are from https://www.postgresql.org/docs/9.3/queries-table-expressions.html#QUERIES-LATERAL
  (testing "FROM can be a LATERAL select"
    (is (= ["SELECT * FROM foo, LATERAL (SELECT * FROM bar WHERE bar.id = foo.bar_id) AS ss"]
           (sql/format {:select :*
                        :from [:foo
                               [[:lateral {:select :*
                                           :from :bar
                                           :where [:= :bar.id :foo.bar_id]}] :ss]]}))))
  (testing "FROM can be a LATERAL expression"
    (is (= [(str "SELECT p1.id, p2.id, v1, v2"
                 " FROM polygons AS p1, polygons AS p2,"
                 " LATERAL VERTICES(p1.poly) AS v1,"
                 " LATERAL VERTICES(p2.poly) AS v2"
                 " WHERE ((v1 <-> v2) < ?) AND (p1.id <> p2.id)") 10]
           (sql/format {:select [:p1.id :p2.id :v1 :v2]
                        :from [[:polygons :p1] [:polygons :p2]
                               [[:lateral [:vertices :p1.poly]] :v1]
                               [[:lateral [:vertices :p2.poly]] :v2]]
                        :where [:and [:< [:<-> :v1 :v2] 10] [:!= :p1.id :p2.id]]})))
    (is (= [(str "SELECT m.name"
                 " FROM manufacturers AS m"
                 " LEFT JOIN LATERAL GET_PRODUCT_NAMES(m.id) AS pname ON TRUE"
                 " WHERE pname IS NULL")]
           (sql/format {:select :m.name
                        :from [[:manufacturers :m]]
                        :left-join [[[:lateral [:get_product_names :m.id]] :pname] true]
                        :where [:= :pname nil]})))))