Allow defaults query in preset-env (#8897)

packages/babel-preset-env/src/targets-parser.js

@@ -68,6 +68,7 @@ const validateBrowsers = browsers => {
     typeof browsers === "undefined" || isBrowsersQueryValid(browsers),
     `Invalid Option: '${browsers}' is not a valid browserslist query`,
   );
+
   return browsers;
 };
 
@@ -194,12 +195,23 @@ const getTargets = (targets: Object = {}, options: Object = {}): Targets => {
 
   // Parse browsers target via browserslist
   const browsersquery = validateBrowsers(targets.browsers);
+
+  const hasTargets = Object.keys(targets).length > 0;
   const shouldParseBrowsers = !!targets.browsers;
   const shouldSearchForConfig =
-    !options.ignoreBrowserslistConfig && !Object.keys(targets).length;
+    !options.ignoreBrowserslistConfig && !hasTargets;
 
   if (shouldParseBrowsers || shouldSearchForConfig) {
-    browserslist.defaults = objectToBrowserslist(targets);
+    // If no targets are passed, we need to overwrite browserslist's defaults
+    // so that we enable all transforms (acting like the now deprecated
+    // preset-latest).
+    //
+    // Note, if browserslist resolves the config (ex. package.json), then usage
+    // of `defaults` in queries will be different since we don't want to break
+    // the behavior of "no targets is the same as preset-latest".
+    if (!hasTargets) {
+      browserslist.defaults = objectToBrowserslist(targets);
+    }
 
     const browsers = browserslist(browsersquery, {
       path: options.configPath,

packages/babel-preset-env/test/fixtures/preset-options/browserslist-default-via-config/browserslist

@@ -0,0 +1 @@
+defaults

packages/babel-preset-env/test/fixtures/preset-options/browserslist-default-via-config/input.mjs

@@ -0,0 +1 @@
+const test = () => "";

packages/babel-preset-env/test/fixtures/preset-options/browserslist-default-via-config/options.json

@@ -0,0 +1,11 @@
+{
+  "presets": [
+    [
+      "../../../../lib",
+      {
+        "configPath": "packages/babel-preset-env/test/fixtures/preset-options/browserslist-default-via-config",
+        "modules": false
+      }
+    ]
+  ]
+}

packages/babel-preset-env/test/fixtures/preset-options/browserslist-default-via-config/output.mjs

@@ -0,0 +1,3 @@
+var test = function test() {
+  return "";
+};

packages/babel-preset-env/test/fixtures/preset-options/browserslist-defaults-2/input.mjs

@@ -0,0 +1 @@
+const test = (a, [b], c) => "";

packages/babel-preset-env/test/fixtures/preset-options/browserslist-defaults-2/options.json

@@ -0,0 +1,13 @@
+{
+  "presets": [
+    [
+      "../../../../lib",
+      {
+        "targets": {
+          "node": "current",
+          "browsers": ["defaults", "not ie <= 10"]
+        }
+      }
+    ]
+  ]
+}

packages/babel-preset-env/test/fixtures/preset-options/browserslist-defaults-2/output.js

@@ -0,0 +1,16 @@
+"use strict";
+
+function _slicedToArray(arr, i) { return _arrayWithHoles(arr) || _iterableToArrayLimit(arr, i) || _nonIterableRest(); }
+
+function _nonIterableRest() { throw new TypeError("Invalid attempt to destructure non-iterable instance"); }
+
+function _iterableToArrayLimit(arr, i) { var _arr = []; var _n = true; var _d = false; var _e = undefined; try { for (var _i = arr[Symbol.iterator](), _s; !(_n = (_s = _i.next()).done); _n = true) { _arr.push(_s.value); if (i && _arr.length === i) break; } } catch (err) { _d = true; _e = err; } finally { try { if (!_n && _i["return"] != null) _i["return"](); } finally { if (_d) throw _e; } } return _arr; }
+
+function _arrayWithHoles(arr) { if (Array.isArray(arr)) return arr; }
+
+var test = function test(a, _ref, c) {
+  var _ref2 = _slicedToArray(_ref, 1),
+      b = _ref2[0];
+
+  return "";
+};

packages/babel-preset-env/test/fixtures/preset-options/browserslist-defaults/input.mjs

@@ -0,0 +1 @@
+const test = () => "";

packages/babel-preset-env/test/fixtures/preset-options/browserslist-defaults/options.json

@@ -0,0 +1,12 @@
+{
+  "presets": [
+    [
+      "../../../../lib",
+      {
+        "targets": {
+          "browsers": "defaults"
+        }
+      }
+    ]
+  ]
+}

packages/babel-preset-env/test/fixtures/preset-options/browserslist-defaults/output.js

@@ -0,0 +1,5 @@
+"use strict";
+
+var test = function test() {
+  return "";
+};

packages/babel-preset-env/test/targets-parser.spec.js

@@ -20,6 +20,15 @@ describe("getTargets", () => {
     });
   });
 
+  it("allows 'defaults' query", () => {
+    const browserslistDefaults = browserslist.defaults;
+
+    const expected = getTargets({ browsers: browserslistDefaults });
+    const actual = getTargets({ browsers: "defaults" });
+
+    expect(actual).toEqual(expected);
+  });
+
   it("does not clobber browserslists defaults", () => {
     const browserslistDefaults = browserslist.defaults;