[ParseSQL] Find-and-replace for snippets (#43011)

* Support F&R for snippets

[Fixes #42648]

src/metabase/native_query_analyzer/replacement.clj

@@ -29,6 +29,13 @@
   [raw-query]
   (first-unique raw-query #(str (gensym "metabase_sentinel_table_"))))
 
+(defn- gen-snippet-sentinel
+  [raw-query {:keys [content]}]
+  (let [delimited-snippet (fn [sentinel snippet-contents]
+                            (format "/* snippet_start_%s */ %s /* snippet_end_%s */"
+                                    sentinel snippet-contents sentinel))]
+    (first-unique raw-query #(delimited-snippet (gensym "mb_") content))))
+
 (defn- braceify
   [s]
   (format "{{%s}}" s))
@@ -53,7 +60,8 @@
 
       :else
       (let [v         (param->value (:k token))
-            card-ref? (params/ReferencedCardQuery? v)]
+            card-ref? (params/ReferencedCardQuery? v)
+            snippet?  (params/ReferencedQuerySnippet? v)]
         (cond
           card-ref?
           (let [sub (gen-table-sentinel raw-query)]
@@ -61,9 +69,16 @@
                    (str query-so-far sub)
                    (add-tag substitutions sub token)))
 
+          snippet?
+          (let [sub (gen-snippet-sentinel raw-query v)]
+            (recur rest
+                   (str query-so-far sub)
+                   (add-tag substitutions sub token)))
+
           ;; Plain variable
           (and (params/Param? token)
-               (not card-ref?))
+               (not card-ref?)
+               (not snippet?))
           (let [sub (gen-variable-sentinel raw-query)]
             (recur rest
                    (str query-so-far sub)

test/metabase/native_query_analyzer/parameter_substitution_test.clj

@@ -195,6 +195,18 @@
          (->sql (mt/native-query {:template-tags (tags "str_starts")
                                   :query         "SELECT * FROM people WHERE {{str_starts}}"})))))
 
+(deftest snippet-test
+  (testing "With a snippet"
+    (t2.with-temp/with-temp
+      [:model/NativeQuerySnippet {snippet-id :id} {:name    "a lovely snippet"
+                                                   :content "where total > 10"}]
+      (let [og-query "SELECT total FROM orders {{snippet: a lovely snippet}}"]
+        (is (= "SELECT total FROM orders where total > 10"
+               (->sql (mt/native-query {:query         og-query
+                                        :template-tags (assoc-in (lib-native/extract-template-tags og-query)
+                                                                 ["snippet: a lovely snippet" :snippet-id]
+                                                                 snippet-id)}))))))))
+
 (deftest card-ref-test
   (t2.with-temp/with-temp
     [:model/Card {card-id :id} {:type          :model

test/metabase/native_query_analyzer/replacement_test.clj

@@ -56,12 +56,25 @@
                                      "city"   "town"}  ; make sure FFs aren't replaced
                            :tables  {"people" "folk"}})))))
 
-(deftest ^:parallel referenced-card-test
+(deftest referenced-card-test
   (testing "With a reference to a card"
     (t2.with-temp/with-temp
       [:model/Card {card-id :id} {:type          :model
-                                  :dataset_query (mt/native-query {:query "SELECT TOTAL, TAX FROM ORDERS"})}]
-      (is (= (format "SELECT SUBTOTAL FROM {{#%s}} LIMIT 3" card-id)
-             (replace-names (q (format "SELECT TOTAL FROM {{#%s}} LIMIT 3" card-id))
-                            {:columns {"TOTAL" "SUBTOTAL"}
-                             :tables  {"ORDERS" "PURCHASES"}}))))))
+                                  :dataset_query (mt/native-query {:query "SELECT total, tax FROM orders"})}]
+      (is (= (format "SELECT subtotal FROM {{#%s}} LIMIT 3" card-id)
+             (replace-names (q (format "SELECT total FROM {{#%s}} LIMIT 3" card-id))
+                            {:columns {"total" "subtotal"}
+                             :tables  {"orders" "purchases"}}))))))
+
+(deftest snippet-test
+  (testing "With a snippet"
+    (t2.with-temp/with-temp
+      [:model/NativeQuerySnippet {snippet-id :id} {:name    "a lovely snippet"
+                                                   :content "where subtotal > 10"}]
+      (is (= "SELECT amount FROM purchases {{snippet: a lovely snippet}}"
+             (replace-names (assoc-in
+                             (q "SELECT total FROM orders {{snippet: a lovely snippet}}")
+                             [:native :template-tags "snippet: a lovely snippet" :snippet-id]
+                             snippet-id)
+                            {:columns {"total" "amount"}
+                             :tables  {"orders" "purchases"}}))))))