Merge PR 32: Keep parentheses around function argument select statements

Author: nene

package.json

@@ -2,7 +2,10 @@
   "name": "prettier-plugin-sql-cst",
   "version": "0.11.6",
   "description": "Prettier plugin for SQL",
-  "author": "Rene Saarsoo <nene@triin.net>",
+  "contributors": [
+    "Bowen Parnell <bparnell@4tel.com.au>",
+    "Rene Saarsoo <nene@triin.net>"
+  ],
   "license": "GPL-3.0-or-later",
   "main": "dist/index.js",
   "types": "dist/index.d.ts",

src/node_utils.ts

@@ -20,6 +20,8 @@ export const isStringLiteral = is("string_literal");
 export const isArraySubscript = is("array_subscript");
 export const isAsClause = is("as_clause");
 export const isParenExpr = is("paren_expr");
+export const isSelectStmt = is("select_stmt");
+export const isCompoundSelectStmt = is("compound_select_stmt");
 export const isListExpr = is("list_expr");
 export const isCreateFunctionStmt = is("create_function_stmt");
 export const isLanguageClause = is("language_clause");

src/syntax/expr.ts

@@ -19,6 +19,8 @@ import {
   isFuncArgs,
   isListExpr,
   isProgram,
+  isSelectStmt,
+  isCompoundSelectStmt,
 } from "../node_utils";
 import { isString, last } from "../utils";
 
@@ -48,7 +50,9 @@ export const exprMap: CstToDocMap<AllExprNodes> = {
     // Discard unnecessary parenthesis around function arguments
     if (
       isListExpr(path.getParentNode(0)) &&
-      isFuncArgs(path.getParentNode(1))
+      isFuncArgs(path.getParentNode(1)) &&
+      !isSelectStmt(node.expr) &&
+      !isCompoundSelectStmt(node.expr)
     ) {
       return print("expr");
     }

test/expr/expr.test.ts

@@ -110,6 +110,27 @@ describe("expr", () => {
     `);
   });
 
+  it(`preserves parenthesis around SELECT inside function arguments`, async () => {
+    await test(dedent`
+      SELECT coalesce((SELECT foo FROM bar), 'default') FROM tbl
+    `);
+  });
+
+  it(`preserves parenthesis around compound-SELECT inside function arguments`, async () => {
+    await test(dedent`
+      SELECT
+        coalesce(
+          '',
+          (
+            SELECT x FROM xs
+            UNION
+            SELECT y FROM ys
+          )
+        )
+      FROM tbl
+    `);
+  });
+
   describe("case", () => {
     it(`formats CASE expression always on multiple lines`, async () => {
       await test(dedent`