feat: remove commented out bindings (fixes #107)

package.json

@@ -29,6 +29,7 @@
     "pg-copy-streams": "^5.1.1",
     "pg-copy-streams-binary": "^2.0.1",
     "pg-cursor": "^2.7.0",
+    "pg-minify": "^1.6.2",
     "postgres-array": "^3.0.1",
     "postgres-interval": "^3.0.0",
     "promise-deferred": "^2.0.3",

src/routines/executeQuery.ts

@@ -23,6 +23,7 @@ import {
 import {
   createQueryId,
   normaliseQueryValues,
+  removeCommentedOutBindings,
 } from '../utilities';
 import type {
   ClientConfigurationType,
@@ -191,6 +192,8 @@ export const executeQuery = async (
     }
   }
 
+  actualQuery = removeCommentedOutBindings(actualQuery);
+
   let result: GenericQueryResult | null;
 
   for (const interceptor of clientConfiguration.interceptors) {

src/utilities/index.ts

@@ -22,6 +22,9 @@ export {
 export {
   normaliseQueryValues,
 } from './normaliseQueryValues';
+export {
+  removeCommentedOutBindings,
+} from './removeCommentedOutBindings';
 export {
   stripArrayNotation,
 } from './stripArrayNotation';

src/utilities/removeCommentedOutBindings.ts

@@ -0,0 +1,58 @@
+// @flow
+
+import minify from 'pg-minify';
+import type {
+  QueryType,
+} from '../types';
+
+const matchAllBindings = (sql: string) => {
+  return Array
+    .from(
+      sql.matchAll(/(\$\d+)/g),
+    )
+    .map((match) => {
+      return Number(match[0].slice(1));
+    })
+    .sort((a, b) => {
+      return a - b;
+    });
+};
+
+export const removeCommentedOutBindings = (query: QueryType): QueryType => {
+  const minifiedSql = minify(query.sql);
+  const originalBindings = matchAllBindings(query.sql);
+  const actualBindings = matchAllBindings(minifiedSql);
+
+  let finalSql = minifiedSql;
+
+  const finalValues = [];
+
+  let lastFoundBinding = 0;
+
+  for (const originalBinding of originalBindings) {
+    if (actualBindings.includes(originalBinding)) {
+      lastFoundBinding = originalBinding;
+
+      finalValues.push(query.values[originalBinding - 1]);
+
+      continue;
+    }
+
+    const greatestBounding = lastFoundBinding;
+
+    finalSql = finalSql.replace(/(\$\d+)/g, (match) => {
+      const matchedBinding = Number(match.slice(1));
+
+      if (matchedBinding > greatestBounding) {
+        return '$' + String(matchedBinding - 1);
+      } else {
+        return match;
+      }
+    });
+  }
+
+  return {
+    sql: finalSql,
+    values: finalValues,
+  };
+};

test/slonik/utilities/removeCommentedOutBindings.ts

@@ -0,0 +1,91 @@
+import test from 'ava';
+import {
+  removeCommentedOutBindings,
+} from '../../../src/utilities/removeCommentedOutBindings';
+
+test('removes commented out bindings', (t) => {
+  t.deepEqual(
+    removeCommentedOutBindings({
+      sql: 'SELECT $1\n-- $2\n$3',
+      values: [
+        'foo',
+        'bar',
+        'baz',
+      ],
+    }),
+    {
+      sql: 'SELECT $1 $2',
+      values: [
+        'foo',
+        'baz',
+      ],
+    },
+  );
+});
+
+test('removes multiple commented out bindings', (t) => {
+  t.deepEqual(
+    removeCommentedOutBindings({
+      sql: 'SELECT $1\n-- $2\n$3\n-- $4\n$5',
+      values: [
+        'foo',
+        'bar',
+        'baz',
+        'qux',
+        'quux',
+      ],
+    }),
+    {
+      sql: 'SELECT $1 $2 $3',
+      values: [
+        'foo',
+        'baz',
+        'quux',
+      ],
+    },
+  );
+});
+
+test('removes multiple bindings in the same comment', (t) => {
+  t.deepEqual(
+    removeCommentedOutBindings({
+      sql: 'SELECT $1\n-- $2 $3 $4\n$5',
+      values: [
+        'foo',
+        'bar',
+        'baz',
+        'qux',
+        'quux',
+      ],
+    }),
+    {
+      sql: 'SELECT $1 $2',
+      values: [
+        'foo',
+        'quux',
+      ],
+    },
+  );
+});
+
+test('removes multiple bindings in the same comment (block comment)', (t) => {
+  t.deepEqual(
+    removeCommentedOutBindings({
+      sql: 'SELECT $1 /* $2 $3 $4 */ $5',
+      values: [
+        'foo',
+        'bar',
+        'baz',
+        'qux',
+        'quux',
+      ],
+    }),
+    {
+      sql: 'SELECT $1 $2',
+      values: [
+        'foo',
+        'quux',
+      ],
+    },
+  );
+});