Generalize $$-string tests

Author: nene

test/duckdb.test.ts

@@ -52,7 +52,7 @@ describe('DuckDBFormatter', () => {
   supportsOnConflict(format);
   supportsUpdate(format);
   supportsTruncateTable(format, { withTable: false, withoutTable: true });
-  supportsStrings(format, ["''-qq", "X''", "B''", "E''"]);
+  supportsStrings(format, ["''-qq", "X''", "B''", "E''", '$$']);
   supportsIdentifiers(format, [`""-qq`]);
   supportsBetween(format);
   // Missing: '::' type cast (tested separately)
@@ -137,26 +137,6 @@ describe('DuckDBFormatter', () => {
     `);
   });
 
-  // DuckDB-specific string types
-  it('supports basic dollar-quoted strings', () => {
-    expect(format('$$foo JOIN bar$$')).toBe('$$foo JOIN bar$$');
-    expect(format('$$foo $ JOIN bar$$')).toBe('$$foo $ JOIN bar$$');
-    expect(format('$$foo \n bar$$')).toBe('$$foo \n bar$$');
-    expect(format('SELECT $$where$$ FROM $$update$$')).toBe(dedent`
-      SELECT
-        $$where$$
-      FROM
-        $$update$$
-    `);
-  });
-
-  // TODO: this conflicts with named parameter syntax: $foo
-  it.skip('supports tagged dollar-quoted strings', () => {
-    expect(format('$xxx$foo $$ LEFT JOIN $yyy$ bar$xxx$')).toBe(
-      '$xxx$foo $$ LEFT JOIN $yyy$ bar$xxx$'
-    );
-  });
-
   it('formats type-cast operator without spaces', () => {
     expect(format('SELECT 2 :: numeric AS foo;')).toBe(dedent`
       SELECT

test/features/strings.ts

@@ -18,7 +18,8 @@ type StringType =
   | 'B""' // no escaping
   | "R''" // no escaping
   | 'R""' // no escaping
-  | "E''"; // with backslash escaping
+  | "E''" // with backslash escaping
+  | '$$'; // no escaping
 
 export default function supportsStrings(format: FormatFn, stringTypes: StringType[]) {
   if (stringTypes.includes('""-qq') || stringTypes.includes('""-bs')) {
@@ -257,4 +258,25 @@ export default function supportsStrings(format: FormatFn, stringTypes: StringTyp
       expect(format(`e'a ha'e'hm mm'`)).toBe(`e'a ha' e'hm mm'`);
     });
   }
+
+  if (stringTypes.includes('$$')) {
+    it('supports dollar-quoted strings', () => {
+      expect(format('$$foo JOIN bar$$')).toBe('$$foo JOIN bar$$');
+      expect(format('$$foo $ JOIN bar$$')).toBe('$$foo $ JOIN bar$$');
+      expect(format('$$foo \n bar$$')).toBe('$$foo \n bar$$');
+      expect(format('SELECT $$where$$ FROM $$update$$')).toBe(dedent`
+        SELECT
+          $$where$$
+        FROM
+          $$update$$
+      `);
+    });
+
+    // TODO: this conflicts with named parameter syntax: $foo
+    it.skip('supports tagged dollar-quoted strings', () => {
+      expect(format('$xxx$foo $$ LEFT JOIN $yyy$ bar$xxx$')).toBe(
+        '$xxx$foo $$ LEFT JOIN $yyy$ bar$xxx$'
+      );
+    });
+  }
 }

test/postgresql.test.ts

@@ -55,7 +55,7 @@ describe('PostgreSqlFormatter', () => {
   supportsOnConflict(format);
   supportsUpdate(format, { whereCurrentOf: true });
   supportsTruncateTable(format, { withoutTable: true });
-  supportsStrings(format, ["''-qq", "U&''", "X''", "B''", "E''"]);
+  supportsStrings(format, ["''-qq", "U&''", "X''", "B''", "E''", '$$']);
   supportsIdentifiers(format, [`""-qq`, 'U&""']);
   supportsBetween(format);
   supportsSchema(format);
@@ -172,22 +172,6 @@ describe('PostgreSqlFormatter', () => {
     `);
   });
 
-  // Postgres-specific string types
-  it('supports dollar-quoted strings', () => {
-    expect(format('$xxx$foo $$ LEFT JOIN $yyy$ bar$xxx$')).toBe(
-      '$xxx$foo $$ LEFT JOIN $yyy$ bar$xxx$'
-    );
-    expect(format('$$foo JOIN bar$$')).toBe('$$foo JOIN bar$$');
-    expect(format('$$foo $ JOIN bar$$')).toBe('$$foo $ JOIN bar$$');
-    expect(format('$$foo \n bar$$')).toBe('$$foo \n bar$$');
-    expect(format('SELECT $$where$$ FROM $$update$$')).toBe(dedent`
-      SELECT
-        $$where$$
-      FROM
-        $$update$$
-    `);
-  });
-
   it('formats type-cast operator without spaces', () => {
     expect(format('SELECT 2 :: numeric AS foo;')).toBe(dedent`
       SELECT