fix: preserve trailing comma in optional call args (#17781)

packages/babel-generator/src/generators/expressions.ts

@@ -71,6 +71,24 @@ export function ConditionalExpression(
   this.print(node.alternate);
 }
 
+function _printExpressionArguments(
+  this: Printer,
+  node: t.CallExpression | t.NewExpression | t.OptionalCallExpression,
+) {
+  this.token("(");
+  const oldNoLineTerminatorAfterNode = this.enterDelimited();
+  this.printList(
+    node.arguments,
+    this.shouldPrintTrailingComma(")"),
+    undefined,
+    undefined,
+    undefined,
+    true,
+  );
+  this._noLineTerminatorAfterNode = oldNoLineTerminatorAfterNode;
+  this.rightParens(node);
+}
+
 export function NewExpression(
   this: Printer,
   node: t.NewExpression,
@@ -99,18 +117,7 @@ export function NewExpression(
     return;
   }
 
-  this.token("(");
-  const oldNoLineTerminatorAfterNode = this.enterDelimited();
-  this.printList(
-    node.arguments,
-    this.shouldPrintTrailingComma(")"),
-    undefined,
-    undefined,
-    undefined,
-    true,
-  );
-  this._noLineTerminatorAfterNode = oldNoLineTerminatorAfterNode;
-  this.rightParens(node);
+  _printExpressionArguments.call(this, node);
 }
 
 export function SequenceExpression(this: Printer, node: t.SequenceExpression) {
@@ -186,18 +193,7 @@ export function OptionalCallExpression(
 
   this.print(node.typeArguments);
 
-  this.token("(");
-  const oldNoLineTerminatorAfterNode = this.enterDelimited();
-  this.printList(
-    node.arguments,
-    undefined,
-    undefined,
-    undefined,
-    undefined,
-    true,
-  );
-  this._noLineTerminatorAfterNode = oldNoLineTerminatorAfterNode;
-  this.rightParens(node);
+  _printExpressionArguments.call(this, node);
 }
 
 export function CallExpression(this: Printer, node: t.CallExpression) {
@@ -205,18 +201,7 @@ export function CallExpression(this: Printer, node: t.CallExpression) {
 
   this.print(node.typeArguments);
 
-  this.token("(");
-  const oldNoLineTerminatorAfterNode = this.enterDelimited();
-  this.printList(
-    node.arguments,
-    this.shouldPrintTrailingComma(")"),
-    undefined,
-    undefined,
-    undefined,
-    true,
-  );
-  this._noLineTerminatorAfterNode = oldNoLineTerminatorAfterNode;
-  this.rightParens(node);
+  _printExpressionArguments.call(this, node);
 }
 
 export function Import(this: Printer) {

packages/babel-generator/src/printer.ts

@@ -398,13 +398,15 @@ class Printer {
   /**
    * Writes a simple token.
    *
-   * @param {string} str The string to append.
-   * @param {boolean} [maybeNewline=false] Wether `str` might potentially
+   * @param str The string to append.
+   * @param [maybeNewline=false] Whether `str` might potentially
    *    contain a line terminator or not.
-   * @param {number} [occurrenceCount=0] The occurrence count of this token in
+   * @param [occurrenceCount=0] The occurrence count of this token in
    *    the current node. This is used when printing in `preserveFormat` mode,
    *    to know which token we should map to (for example, to disambiguate the
    *    commas in an array literal).
+   * @param [mayNeedSpace=false] Check whether a whitespace might be
+   *    needed after this token, and if so, add a whitespace after it.
    */
   token(
     str: string,

packages/babel-generator/test/fixtures/types/CallExpression/input.js

@@ -3,3 +3,7 @@ foo("foo");
 foo("foo", "bar");
 foo(bar());
 foo(bar("test"));
+foo(
+  "foo",
+  "bar",
+);

packages/babel-generator/test/fixtures/types/CallExpression/output.js

@@ -2,4 +2,5 @@ foo();
 foo("foo");
 foo("foo", "bar");
 foo(bar());
-foo(bar("test"));
+foo(bar("test"));
+foo("foo", "bar");

packages/babel-generator/test/fixtures/types/NewExpression/input.js

@@ -1,3 +1,7 @@
 new Foo;
 new Foo();
 new Foo(bar);
+new Foo(
+  bar,
+  baz,
+)

packages/babel-generator/test/fixtures/types/NewExpression/output.js

@@ -1,3 +1,4 @@
 new Foo();
 new Foo();
-new Foo(bar);
+new Foo(bar);
+new Foo(bar, baz);

packages/babel-generator/test/fixtures/types/Optional-CallExpression/input.js

@@ -41,3 +41,9 @@ a.foo?.(bar())?.baz;
 a.foo?.(bar("test"))?.baz;
 a.foo(bar?.())?.baz;
 a.foo(bar?.("test"))?.baz;
+a?.foo(
+  "foo",
+  "bar",
+)(
+  "baz",
+)

packages/babel-generator/test/fixtures/types/Optional-CallExpression/output.js

@@ -40,4 +40,5 @@ a.foo?.("foo", "bar")?.baz;
 a.foo?.(bar())?.baz;
 a.foo?.(bar("test"))?.baz;
 a.foo(bar?.())?.baz;
-a.foo(bar?.("test"))?.baz;
+a.foo(bar?.("test"))?.baz;
+a?.foo("foo", "bar")("baz");