Merge PR #276: Support arrays in PostgreSQL

Author: nene

sql/arrays-and-maps.md

@@ -9,6 +9,11 @@ Array literals `[1, "two", 3]`. Supported by:
 - [BigQuery][bigquery-literals].
 - [N1QL][n1ql-literals].
 
+Array literals `ARRAY[1, 2, 3]`. Supported by:
+
+- [BigQuery][bigquery-literals].
+- [PostgreSQL][postgres-literals].
+
 Map literals in JSON style `{"foo": 1, "bar": "John"}`. Supported by:
 
 - [N1QL][n1ql-literals].
@@ -22,9 +27,17 @@ Supported by:
 - [Hive][]
 - [Spark][]
 - [N1QL][]
+- [PostgreSQL][]
+
+Array subscript operator `arr[OFFSET(5)]`. Supported by:
+
+- [BigQuery][]
 
+[bigquery]: https://cloud.google.com/bigquery/docs/reference/standard-sql/operators#array_subscript_operator
 [hive]: https://cwiki.apache.org/confluence/display/Hive/LanguageManual+UDF#LanguageManualUDF-OperatorsonComplexTypes
 [spark]: https://stackoverflow.com/questions/34916038/sparksql-sql-syntax-for-nth-item-in-array
 [n1ql-literals]: https://docs.couchbase.com/server/current/n1ql/n1ql-language-reference/datatypes.html#arrays
 [n1ql]: https://docs.couchbase.com/server/current/n1ql/n1ql-language-reference/nestedops.html#field-selection
+[postgresql]: https://www.postgresql.org/docs/current/arrays.html#ARRAYS-ACCESSING
 [bigquery-literals]: https://cloud.google.com/bigquery/docs/reference/standard-sql/lexical#array_literals
+[postgres-literals]: https://www.postgresql.org/docs/current/arrays.html

src/languages/postgresql.formatter.ts

@@ -1675,6 +1675,8 @@ export default class PostgreSqlFormatter extends Formatter {
       reservedJoins,
       reservedDependentClauses,
       reservedKeywords: dedupe([...Object.values(reservedFunctions).flat(), ...reservedKeywords]),
+      openParens: ['(', '['],
+      closeParens: [')', ']'],
       stringTypes: [{ quote: "''", prefixes: ['U&', 'E', 'X', 'B'] }, '$$'],
       identTypes: [{ quote: '""', prefixes: ['U&'] }],
       identChars: { rest: '$' },

test/postgresql.test.ts

@@ -17,6 +17,7 @@ import supportsDeleteFrom from './features/deleteFrom';
 import supportsComments from './features/comments';
 import supportsIdentifiers from './features/identifiers';
 import supportsParams from './options/param';
+import supportsArrayAndMapAccessors from './features/arrayAndMapAccessors';
 
 describe('PostgreSqlFormatter', () => {
   const language = 'postgresql';
@@ -26,6 +27,7 @@ describe('PostgreSqlFormatter', () => {
   supportsComments(format);
   supportsCreateTable(format);
   supportsConstraints(format);
+  supportsArrayAndMapAccessors(format);
   supportsAlterTable(format);
   supportsDeleteFrom(format);
   supportsStrings(format, ["''", "U&''", "X''"]);
@@ -79,4 +81,11 @@ describe('PostgreSqlFormatter', () => {
         $$update$$
     `);
   });
+
+  it('supports ARRAY literals', () => {
+    expect(format('SELECT ARRAY[1, 2, 3]')).toBe(dedent`
+      SELECT
+        ARRAY[1, 2, 3]
+    `);
+  });
 });