Parse PostgreSQL array literals differently from BigQuery array literals

- ARRAY[1,2] in postgres will now result in array_literal_expr
- ARRAY[1,2] in bigquery will result in typed_expr (as before)

Fixes #127

Author: nene

src/cst/Expr.ts

@@ -64,6 +64,7 @@ export type Expr =
   | Variable
   | Parameter
   | TypedExpr
+  | ArrayLiteralExpr
   | ArrayExpr
   | StructExpr;
 
@@ -509,14 +510,20 @@ export interface Parameter extends BaseNode {
   text: string;
 }
 
-// BigQuery, PostgreSQL
-// TODO: It feels awkward that PostgreSQL array literals have the ARRAY type attached to them
+// BigQuery
 export interface TypedExpr extends BaseNode {
   type: "typed_expr";
   dataType: DataType;
   expr: ArrayExpr | StructExpr;
 }
 
+// PostgreSQL
+export interface ArrayLiteralExpr extends BaseNode {
+  type: "array_literal_expr";
+  arrayKw: Keyword<"ARRAY">;
+  expr: ArrayExpr;
+}
+
 // BigQuery, PostgreSQL
 export interface ArrayExpr extends BaseNode {
   type: "array_expr";

src/parser.pegjs

@@ -7770,7 +7770,7 @@ primary
   / primary_paren_expr
   / paren$compound_select_stmt
   / &bigquery x:(typed_array_expr / array_expr / typed_struct_expr) { return x; }
-  / &postgres x:typed_array_expr { return x; }
+  / &postgres x:array_literal_expr { return x; }
   / cast_expr
   / &postgres x:(row_constructor / array_constructor) { return x; }
   / &sqlite e:raise_expr { return e; }
@@ -8669,6 +8669,15 @@ system_variable
  *                                                                                      *
  * ------------------------------------------------------------------------------------ *
  */
+array_literal_expr
+  = kw:(ARRAY __) expr:array_expr {
+    return loc({
+      type: "array_literal_expr",
+      arrayKw: read(kw),
+      expr,
+    });
+  }
+
 typed_array_expr
   = type:(bigquery_array_type __) expr:array_expr {
     return loc({

src/showNode/expr.ts

@@ -44,6 +44,7 @@ export const exprMap: FullTransformMap<string, AllExprNodes> = {
   interval_unit_range: (node) => show([node.fromUnit, node.toKw, node.toUnit]),
   interval_unit: (node) => show([node.unitKw]),
   typed_expr: (node) => show([node.dataType, node.expr]),
+  array_literal_expr: (node) => show([node.arrayKw, node.expr]),
   array_expr: (node) => show(["[", node.expr, "]"]),
   struct_expr: (node) => show(["(", node.expr, ")"]),
   quantifier_expr: (node) => show([node.quantifierKw, node.expr]),

test/expr/array.test.ts

@@ -86,6 +86,37 @@ describe("array", () => {
     it("supports ARRAY() constructor", () => {
       testExprWc(`ARRAY(SELECT row from tbl)`);
     });
+
+    it("parses array literal", () => {
+      expect(parseExpr(`ARRAY[1, 2]`)).toMatchInlineSnapshot(`
+        {
+          "arrayKw": {
+            "name": "ARRAY",
+            "text": "ARRAY",
+            "type": "keyword",
+          },
+          "expr": {
+            "expr": {
+              "items": [
+                {
+                  "text": "1",
+                  "type": "number_literal",
+                  "value": 1,
+                },
+                {
+                  "text": "2",
+                  "type": "number_literal",
+                  "value": 2,
+                },
+              ],
+              "type": "list_expr",
+            },
+            "type": "array_expr",
+          },
+          "type": "array_literal_expr",
+        }
+      `);
+    });
   });
 
   dialect(["mysql", "mariadb"], () => {