Improve formatting for do expression (#10693)

changelog_unreleased/javascript/10693.md

@@ -0,0 +1,24 @@
+#### Improve formatting for do expression (#10693 by @sosukesuzuki)
+
+<!-- prettier-ignore -->
+```js
+// Input
+expect(do {
+  var bar = "foo";
+  bar;
+}).toBe("foo");
+
+// Prettier stable
+expect(
+  do {
+    var bar = "foo";
+    bar;
+  }
+).toBe("foo");
+
+// Prettier main
+expect(do {
+  var bar = "foo";
+  bar;
+}).toBe("foo");
+```

src/language-js/print/call-arguments.js

@@ -247,7 +247,8 @@ function couldGroupArg(arg, arrowChainRecursion = false) {
         (!arrowChainRecursion &&
           (isCallExpression(arg.body) ||
             arg.body.type === "ConditionalExpression")) ||
-        isJsxNode(arg.body)))
+        isJsxNode(arg.body))) ||
+    arg.type === "DoExpression"
   );
 }
 

tests/js/do/__snapshots__/jsfmt.spec.js.snap

@@ -1,5 +1,113 @@
 // Jest Snapshot v1, https://goo.gl/fbAQLP
 
+exports[`call-arguments.js [espree] format 1`] = `
+"Unexpected token do (3:3)
+  1 | // from https://github.com/babel/babel/pull/13122/
+  2 | expect(
+> 3 |   do {
+    |   ^
+  4 |     var bar = \\"foo\\";
+  5 |     if (!bar) throw new Error(
+  6 |       \\"unreachable\\""
+`;
+
+exports[`call-arguments.js [meriyah] format 1`] = `
+"[3:4]: Unexpected token: 'do' (3:4)
+  1 | // from https://github.com/babel/babel/pull/13122/
+  2 | expect(
+> 3 |   do {
+    |    ^
+  4 |     var bar = \\"foo\\";
+  5 |     if (!bar) throw new Error(
+  6 |       \\"unreachable\\""
+`;
+
+exports[`call-arguments.js format 1`] = `
+====================================options=====================================
+parsers: ["babel"]
+printWidth: 80
+                                                                                | printWidth
+=====================================input======================================
+// from https://github.com/babel/babel/pull/13122/
+expect(
+  do {
+    var bar = "foo";
+    if (!bar) throw new Error(
+      "unreachable"
+    )
+    bar;
+  }
+).toBe("foo");
+expect(bar).toBe("foo");
+
+var x = do {
+  var bar = "foo";
+  if (!bar) throw new Error(
+    "unreachable"
+  )
+  bar;
+};
+
+expect(
+  do {
+    var bar = "foo";
+    bar;
+  }
+).toBe("foo");
+expect(bar).toBe("foo");
+
+var x = do {
+  var bar = "foo";
+  bar;
+};
+
+expect(
+  () => do {
+    () => {
+      var bar = "foo";
+    };
+    bar;
+  }
+).toThrow(ReferenceError);
+
+=====================================output=====================================
+// from https://github.com/babel/babel/pull/13122/
+expect(do {
+  var bar = "foo";
+  if (!bar) throw new Error("unreachable");
+  bar;
+}).toBe("foo");
+expect(bar).toBe("foo");
+
+var x = do {
+  var bar = "foo";
+  if (!bar) throw new Error("unreachable");
+  bar;
+};
+
+expect(do {
+  var bar = "foo";
+  bar;
+}).toBe("foo");
+expect(bar).toBe("foo");
+
+var x = do {
+  var bar = "foo";
+  bar;
+};
+
+expect(
+  () => do {
+    () => {
+      var bar = "foo";
+    };
+    bar;
+  }
+).toThrow(ReferenceError);
+
+================================================================================
+`;
+
 exports[`do.js [espree] format 1`] = `
 "Unexpected token do (3:5)
   1 | const envSpecific = {

tests/js/do/call-arguments.js

@@ -0,0 +1,41 @@
+// from https://github.com/babel/babel/pull/13122/
+expect(
+  do {
+    var bar = "foo";
+    if (!bar) throw new Error(
+      "unreachable"
+    )
+    bar;
+  }
+).toBe("foo");
+expect(bar).toBe("foo");
+
+var x = do {
+  var bar = "foo";
+  if (!bar) throw new Error(
+    "unreachable"
+  )
+  bar;
+};
+
+expect(
+  do {
+    var bar = "foo";
+    bar;
+  }
+).toBe("foo");
+expect(bar).toBe("foo");
+
+var x = do {
+  var bar = "foo";
+  bar;
+};
+
+expect(
+  () => do {
+    () => {
+      var bar = "foo";
+    };
+    bar;
+  }
+).toThrow(ReferenceError);