part of #570 -- colon path selection

Signed-off-by: Sean Corfield <sean@corfield.org>

CHANGELOG.md

@@ -1,6 +1,7 @@
 # Changes
 
 * 2.7.next in progress
+  * Address #570 by adding `:.:.` as special syntax for Snowflake's JSON path syntax.
   * Drop support for Clojure 1.9 [#561](https://github.com/seancorfield/honeysql/issues/561).
 
 * 2.6.1281 -- 2025-03-06

doc/special-syntax.md

@@ -211,15 +211,23 @@ Accepts a single expression and prefixes it with `DISTINCT `:
 ;;=> ["SELECT COUNT(DISTINCT status) AS n FROM table"]
 ```
 
-## dot .
+## dot . .:.
 
-Accepts an expression and a field (or column) selection:
+Accepts an expression and one or more fields (or columns). Plain dot produces
+plain dotted selection:
 
 ```clojure
 (sql/format {:select [ [[:. :t :c]] [[:. :s :t :c]] ]})
 ;;=> ["SELECT t.c, s.t.c"]
 ```
 
+Dot colon dot produces Snowflake-style dotted selection:
+
+```clojure
+(sql/format {:select [ [[:.:. :t :c]] [[:.:. :s :t :c]] ]})
+;;=> ["SELECT t:c, s:t.c"]
+```
+
 Can be used with `:nest` for field selection from composites:
 
 ```clojure

src/honey/sql.cljc

@@ -1946,6 +1946,12 @@
   (let [[sql & params] (format-expr x)]
     (into [(str sql " " (sql-kw k))] params)))
 
+(defn dot-navigation [sep [expr col & subcols]]
+  (let [[sql & params] (format-expr expr)]
+    (into [(str sql sep (format-entity col)
+                (when (seq subcols)
+                  (str "." (join "." (map format-entity subcols)))))]
+          params)))
 (def ^:private special-syntax
   (atom
    {;; these "functions" are mostly used in column
@@ -1966,12 +1972,9 @@
     :references  #'function-1
     :unique      #'function-1-opt
     ;; dynamic dotted name creation:
-    :.           (fn [_ [expr col subcol]]
+    :.           (fn [_ data] (dot-navigation "." data))
-                   (let [[sql & params] (format-expr expr)]
+    ;; snowflake variant #570:
-                     (into [(str sql "." (format-entity col)
+    :.:.         (fn [_ data] (dot-navigation ":" data))
-                                 (when subcol
-                                   (str "." (format-entity subcol))))]
-                           params)))
     ;; used in DDL to force rendering as a SQL entity instead
     ;; of a SQL keyword:
     :entity      (fn [_ [e]] [(format-entity e)])

test/honey/sql_test.cljc

@@ -1178,9 +1178,10 @@ ORDER BY id = ? DESC
 
 (deftest issue-474-dot-selection
   (testing "basic dot selection"
-    (is (= ["SELECT a.b, c.d, a.d.x"]
+    (is (= ["SELECT a.b, c.d, a.d.x, a.d.x.y"]
            (let [t :a c :d]
-             (sut/format {:select [[[:. t :b]] [[:. :c c]] [[:. t c :x]]]}))))
+             (sut/format {:select [[[:. t :b]] [[:. :c c]]
+                                   [[:. t c :x]] [[:. t c :x :y]]]}))))
     (is (= ["SELECT [a].[b], [c].[d], [a].[d].[x]"]
            (let [t :a c :d]
              (sut/format {:select [[[:. t :b]] [[:. :c c]] [[:. t c :x]]]}
@@ -1194,6 +1195,45 @@ ORDER BY id = ? DESC
            (sut/format '{select (((. (nest v) *))
                                  ((. (nest w) x))
                                  ((. (nest (y z)) *)))}
+                       {:dialect :mysql})))
+    (is (= ["SELECT (v).*, (w).x, (Y(z)).*"]
+           (sut/format '{select (((get-in v *))
+                                 ((get-in w x))
+                                 ((get-in (y z) *)))})))
+    (is (= ["SELECT (`v`).*, (`w`).`x`, (Y(`z`)).*"]
+           (sut/format '{select (((get-in v *))
+                                 ((get-in w x))
+                                 ((get-in (y z) *)))}
+                       {:dialect :mysql})))))
+
+(deftest issue-570-snowflake-dot-selection
+  (testing "basic colon selection"
+    (is (= ["SELECT a:b, c:d, a:d.x, a:d.x.y"]
+           (let [t :a c :d]
+             (sut/format {:select [[[:.:. t :b]] [[:.:. :c c]]
+                                   [[:.:. t c :x]] [[:.:. t c :x :y]]]}))))
+    (is (= ["SELECT [a]:[b], [c]:[d], [a]:[d].[x]"]
+           (let [t :a c :d]
+             (sut/format {:select [[[:.:. t :b]] [[:.:. :c c]] [[:.:. t c :x]]]}
+                         {:dialect :sqlserver})))))
+  (testing "basic field selection from composite"
+    (is (= ["SELECT (v):*, (w):x, (Y(z)):*"]
+           (sut/format '{select (((.:. (nest v) *))
+                                 ((.:. (nest w) x))
+                                 ((.:. (nest (y z)) *)))})))
+    (is (= ["SELECT (`v`):*, (`w`):`x`, (Y(`z`)):*"]
+           (sut/format '{select (((.:. (nest v) *))
+                                 ((.:. (nest w) x))
+                                 ((.:. (nest (y z)) *)))}
+                       {:dialect :mysql})))
+    (is (= ["SELECT (v):*, (w):x, (Y(z)):*"]
+           (sut/format '{select (((get-in v *))
+                                 ((get-in w x))
+                                 ((get-in (y z) *)))})))
+    (is (= ["SELECT (`v`):*, (`w`):`x`, (Y(`z`)):*"]
+           (sut/format '{select (((get-in v *))
+                                 ((get-in w x))
+                                 ((get-in (y z) *)))}
                        {:dialect :mysql})))))
 
 (deftest issue-476-raw
@@ -1451,4 +1491,9 @@ ORDER BY id = ? DESC
     :select          [:*]
     :from            [:a-b.b-c.c-d]}
    (sut/format {:dialect :nrql}))
+  (sut/format {:select :a:b.c}) ; quotes a:b
+  (sut/format [:. :a :b :c]) ; a.b.c
+  (sut/format [:. :a :b :c :d]) ; drops d  ; a.b.c
+  (sut/format [:.:. :a :b :c]) ; .(a, b, c)
+  (sut/format '(.:. a b c)) ; .(a, b, c)
   )