feat(es/minifier): Make seq inliner inline into var without init (#10077)

Author: Austaras

crates/swc/tests/tsc-references/compoundExponentiationAssignmentLHSIsReference.2.minified.js

@@ -1,3 +1,3 @@
 //// [compoundExponentiationAssignmentLHSIsReference.ts]
-var value, x1, x3;
-x1 = Math.pow(x1, value), x3.a = Math.pow(x3.a, value), x3.a = Math.pow(x3.a, value), x1 = Math.pow(x1, value), x3.a = Math.pow(x3.a, value), x3.a = Math.pow(x3.a, value);
+var value, x3, x1 = Math.pow(x1, value);
+x3.a = Math.pow(x3.a, value), x3.a = Math.pow(x3.a, value), x1 = Math.pow(x1, value), x3.a = Math.pow(x3.a, value), x3.a = Math.pow(x3.a, value);

crates/swc/tests/tsc-references/invalidVoidAssignments.2.minified.js

@@ -1,4 +1,4 @@
 //// [invalidVoidAssignments.ts]
 import "@swc/helpers/_/_class_call_check";
-(M || (M = {})).x = 1, M = x;
-var E, x, M, E1 = ((E = E1 || {})[E.A = 0] = "A", E);
+(M || (M = {})).x = 1;
+var E, M = void 0, E1 = ((E = E1 || {})[E.A = 0] = "A", E);

crates/swc_ecma_minifier/src/compress/optimize/sequences.rs

@@ -1,7 +1,7 @@
 use std::{iter::once, mem::take};
 
 use rustc_hash::FxHashSet;
-use swc_common::{pass::Either, util::take::Take, Spanned, DUMMY_SP};
+use swc_common::{pass::Either, util::take::Take, EqIgnoreSpan, Spanned, DUMMY_SP};
 use swc_ecma_ast::*;
 use swc_ecma_usage_analyzer::{
     alias::{try_collect_infects_from, AccessKind, AliasConfig},
@@ -946,7 +946,39 @@ impl Optimizer<'_> {
                                     break;
                                 }
                             }
-                            None => continue,
+                            None => {
+                                if let Mergable::Expr(Expr::Assign(a_exp)) = a {
+                                    if let (Some(a_id), Some(b_id)) =
+                                        (a_exp.left.as_ident(), b.name.as_ident())
+                                    {
+                                        if a_id.id.eq_ignore_span(&b_id.id)
+                                            && a_exp.op == op!("=")
+                                            && self
+                                                .data
+                                                .vars
+                                                .get(&a_id.id.to_id())
+                                                .map(|u| {
+                                                    !u.inline_prevented && !u.declared_as_fn_expr
+                                                })
+                                                .unwrap_or(false)
+                                        {
+                                            changed = true;
+                                            report_change!("merge assign and var decl");
+                                            b.init = Some(a_exp.right.take());
+                                            merge_seq_cache.invalidate(a_idx);
+                                            merge_seq_cache.invalidate(b_idx);
+
+                                            if let Mergable::Expr(e) = a {
+                                                e.take();
+                                            }
+
+                                            break;
+                                        }
+                                    }
+                                }
+
+                                continue;
+                            }
                         },
                         Mergable::Expr(b) => {
                             if !merge_seq_cache.is_top_retain(self, a, a_idx)
@@ -2573,6 +2605,7 @@ impl Optimizer<'_> {
                 in_abort: false,
             };
             b.visit_with(&mut v);
+            println!("{:#?}", v.abort);
             if v.expr_usage != 1 || v.pat_usage != 0 || v.abort {
                 log_abort!(
                     "sequences: Aborting because of usage counts ({}{:?}, ref = {}, pat = {})",

crates/swc_ecma_minifier/tests/benches-full/echarts.js

@@ -17551,8 +17551,7 @@
             each(sysDims, function(sysDimItemRaw) {
                 if (isString(sysDimItemRaw)) coordDim = sysDimItemRaw, sysDimItem = {};
                 else {
-                    coordDim = (sysDimItem = sysDimItemRaw).name;
-                    var coordDim, sysDimItemDimsDef, sysDimItemOtherDims, sysDimItem, ordinalMeta = sysDimItem.ordinalMeta;
+                    var sysDimItemDimsDef, sysDimItemOtherDims, sysDimItem, coordDim = (sysDimItem = sysDimItemRaw).name, ordinalMeta = sysDimItem.ordinalMeta;
                     sysDimItem.ordinalMeta = null, (sysDimItem = clone(sysDimItem)).ordinalMeta = ordinalMeta, sysDimItemDimsDef = sysDimItem.dimsDef, sysDimItemOtherDims = sysDimItem.otherDims, sysDimItem.name = sysDimItem.coordDim = sysDimItem.coordDimIndex = sysDimItem.dimsDef = sysDimItem.otherDims = null;
                 }
                 var dataDims = encodeDefMap.get(coordDim); // negative resultDimIdx means no need to mapping.
@@ -26551,8 +26550,8 @@
     }
     function getEdgeShape(layoutOpt, orient, curvature, sourceLayout, targetLayout) {
         if ('radial' === layoutOpt) {
-            x1 = sourceLayout.rawX, y1 = sourceLayout.rawY, x2 = targetLayout.rawX, y2 = targetLayout.rawY;
-            var cpx1, cpy1, cpx2, cpy2, x1, x2, y1, y2, radialCoor1 = radialCoordinate(x1, y1), radialCoor2 = radialCoordinate(x1, y1 + (y2 - y1) * curvature), radialCoor3 = radialCoordinate(x2, y2 + (y1 - y2) * curvature), radialCoor4 = radialCoordinate(x2, y2);
+            x1 = sourceLayout.rawX, y1 = sourceLayout.rawY, x2 = targetLayout.rawX;
+            var cpx1, cpy1, cpx2, cpy2, x1, x2, y1, y2 = targetLayout.rawY, radialCoor1 = radialCoordinate(x1, y1), radialCoor2 = radialCoordinate(x1, y1 + (y2 - y1) * curvature), radialCoor3 = radialCoordinate(x2, y2 + (y1 - y2) * curvature), radialCoor4 = radialCoordinate(x2, y2);
             return {
                 x1: radialCoor1.x || 0,
                 y1: radialCoor1.y || 0,

crates/swc_ecma_minifier/tests/benches-full/three.js

@@ -11818,9 +11818,7 @@ function(global, factory) {
         },
         // Given u ( 0 .. 1 ), get a t to find p. This gives you points which are equidistant
         getUtoTmapping: function(u, distance) {
-            var arcLengths = this.getLengths(), i = 0, il = arcLengths.length;
-            targetArcLength = distance || u * arcLengths[il - 1]; // binary search for the index with largest value smaller than target u distance
-            for(var targetArcLength, comparison, low = 0, high = il - 1; low <= high;)if ((comparison = arcLengths[i = Math.floor(low + (high - low) / 2)] - targetArcLength) < 0) low = i + 1;
+            for(var comparison, arcLengths = this.getLengths(), i = 0, il = arcLengths.length, targetArcLength = distance || u * arcLengths[il - 1], low = 0, high = il - 1; low <= high;)if ((comparison = arcLengths[i = Math.floor(low + (high - low) / 2)] - targetArcLength) < 0) low = i + 1;
             else if (comparison > 0) high = i - 1;
             else {
                 high = i;
@@ -13057,8 +13055,7 @@ function(global, factory) {
                     object = new Mesh(geometry = getGeometry(data.geometry), material = getMaterial(data.material));
                     break;
                 case 'InstancedMesh':
-                    geometry = getGeometry(data.geometry), material = getMaterial(data.material);
-                    var object, geometry, material, count = data.count, instanceMatrix = data.instanceMatrix;
+                    var object, geometry = getGeometry(data.geometry), material = getMaterial(data.material), count = data.count, instanceMatrix = data.instanceMatrix;
                     (object = new InstancedMesh(geometry, material, count)).instanceMatrix = new BufferAttribute(new Float32Array(instanceMatrix.array), 16);
                     break;
                 case 'LOD':

crates/swc_ecma_minifier/tests/fixture/next/33265/static/chunks/d6e1aeb5-38a8d7ae57119c23/output.js

@@ -2037,8 +2037,7 @@
                  *         `Component` will get created by this process.
                  */ _proto.addChild = function(child, options, index) {
                     if (void 0 === options && (options = {}), void 0 === index && (index = this.children_.length), "string" == typeof child) {
-                        componentName = toTitleCase$1(child);
-                        var component, componentName, componentClassName = options.componentClass || componentName; // Set name through options
+                        var component, componentName = toTitleCase$1(child), componentClassName = options.componentClass || componentName; // Set name through options
                         options.name = componentName; // Create a new object & element for this controls set
                         // If there's no .player_, this is a player
                         var ComponentClass = Component.getComponent(componentClassName);
@@ -3792,8 +3791,8 @@
                  *
                  * @abstract
                  */ function Track(options) {
-                    void 0 === options && (options = {}), _this = _EventTarget.call(this) || this;
-                    var _this, trackProps = {
+                    void 0 === options && (options = {});
+                    var _this = _EventTarget.call(this) || this, trackProps = {
                         id: options.id || "vjs_track_" + _guid++,
                         kind: options.kind || "",
                         language: options.language || ""
@@ -4220,8 +4219,8 @@
                  * @param {boolean} [options.default]
                  *        If this track should default to on or off.
                  */ function HTMLTrackElement(options) {
-                    void 0 === options && (options = {}), _this = _EventTarget.call(this) || this;
-                    var _this, readyState, track = new TextTrack(options);
+                    void 0 === options && (options = {});
+                    var readyState, _this = _EventTarget.call(this) || this, track = new TextTrack(options);
                     return _this.kind = track.kind, _this.src = track.src, _this.srclang = track.language, _this.label = track.label, _this.default = track.default, Object.defineProperties((0, _babel_runtime_helpers_assertThisInitialized__WEBPACK_IMPORTED_MODULE_17__ /* ["default"] */ .Z)(_this), {
                         /**
                              * @memberof HTMLTrackElement
@@ -5593,8 +5592,7 @@
                  * @param {Component~ReadyCallback} [ready]
                  *        The function to call when `TextTrackDisplay` is ready.
                  */ function TextTrackDisplay(player, options, ready) {
-                    _this = _Component.call(this, player, options, ready) || this;
-                    var _this, updateDisplayHandler = function(e) {
+                    var _this = _Component.call(this, player, options, ready) || this, updateDisplayHandler = function(e) {
                         return _this.updateDisplay(e);
                     };
                     return player.on("loadstart", function(e) {
@@ -6259,8 +6257,7 @@
                  * @param {Object} [options]
                  *        The key/value store of player options.
                  */ function DurationDisplay(player, options) {
-                    _this = _TimeDisplay.call(this, player, options) || this;
-                    var _this, updateContent = function(e) {
+                    var _this = _TimeDisplay.call(this, player, options) || this, updateContent = function(e) {
                         return _this.updateContent(e);
                     }; // we do not want to/need to throttle duration changes,
                     return(// as they should always display the changed duration as
@@ -8991,8 +8988,7 @@
                  * @param {Component~ReadyCallback} [ready]
                  *        The function to call when this component is ready.
                  */ function DescriptionsButton(player, options, ready) {
-                    _this = _TextTrackButton.call(this, player, options, ready) || this;
-                    var _this, tracks = player.textTracks(), changeHandler = bind((0, _babel_runtime_helpers_assertThisInitialized__WEBPACK_IMPORTED_MODULE_17__ /* ["default"] */ .Z)(_this), _this.handleTracksChange);
+                    var _this = _TextTrackButton.call(this, player, options, ready) || this, tracks = player.textTracks(), changeHandler = bind((0, _babel_runtime_helpers_assertThisInitialized__WEBPACK_IMPORTED_MODULE_17__ /* ["default"] */ .Z)(_this), _this.handleTracksChange);
                     return tracks.addEventListener("change", changeHandler), _this.on("dispose", function() {
                         tracks.removeEventListener("change", changeHandler);
                     }), _this;
@@ -10612,8 +10608,7 @@
                  * @param {Component~ReadyCallback} ready
                  *        Callback function to call when the `HTML5` Tech is ready.
                  */ function Html5(options, ready) {
-                    _this = _Tech.call(this, options, ready) || this;
-                    var _this, source = options.source, crossoriginTracks = !1;
+                    var _this = _Tech.call(this, options, ready) || this, source = options.source, crossoriginTracks = !1;
                     if (source && (_this.el_.currentSrc !== source.src || options.tag && 3 === options.tag.initNetworkState_) ? _this.setSource(source) : _this.handleLateInit_(_this.el_), options.enableSourceset && _this.setupSourcesetHandling_(), _this.isScrubbing_ = !1, _this.el_.hasChildNodes()) {
                         for(var nodes = _this.el_.childNodes, nodesLength = nodes.length, removeNodes = []; nodesLength--;){
                             var node = nodes[nodesLength];
@@ -25349,8 +25344,7 @@
                 return log("not " + sharedLogLine + " as no switching criteria met"), !1;
             }, MasterPlaylistController = /*#__PURE__*/ function(_videojs$EventTarget) {
                 function MasterPlaylistController(options) {
-                    _this = _videojs$EventTarget.call(this) || this;
-                    var _this, src = options.src, handleManifestRedirects = options.handleManifestRedirects, withCredentials = options.withCredentials, tech = options.tech, bandwidth = options.bandwidth, externVhs = options.externVhs, useCueTags = options.useCueTags, blacklistDuration = options.blacklistDuration, enableLowInitialPlaylist = options.enableLowInitialPlaylist, sourceType = options.sourceType, cacheEncryptionKeys = options.cacheEncryptionKeys, experimentalBufferBasedABR = options.experimentalBufferBasedABR, experimentalLeastPixelDiffSelector = options.experimentalLeastPixelDiffSelector, captionServices = options.captionServices;
+                    var _this = _videojs$EventTarget.call(this) || this, src = options.src, handleManifestRedirects = options.handleManifestRedirects, withCredentials = options.withCredentials, tech = options.tech, bandwidth = options.bandwidth, externVhs = options.externVhs, useCueTags = options.useCueTags, blacklistDuration = options.blacklistDuration, enableLowInitialPlaylist = options.enableLowInitialPlaylist, sourceType = options.sourceType, cacheEncryptionKeys = options.cacheEncryptionKeys, experimentalBufferBasedABR = options.experimentalBufferBasedABR, experimentalLeastPixelDiffSelector = options.experimentalLeastPixelDiffSelector, captionServices = options.captionServices;
                     if (!src) throw Error("A non-empty playlist URL or JSON manifest string is required");
                     var maxPlaylistRetries = options.maxPlaylistRetries;
                     null == maxPlaylistRetries && (maxPlaylistRetries = 1 / 0), Vhs$1 = externVhs, _this.experimentalBufferBasedABR = !!experimentalBufferBasedABR, _this.experimentalLeastPixelDiffSelector = !!experimentalLeastPixelDiffSelector, _this.withCredentials = withCredentials, _this.tech_ = tech, _this.vhs_ = tech.vhs, _this.sourceType_ = sourceType, _this.useCueTags_ = useCueTags, _this.blacklistDuration = blacklistDuration, _this.maxPlaylistRetries = maxPlaylistRetries, _this.enableLowInitialPlaylist = enableLowInitialPlaylist, _this.useCueTags_ && (_this.cueTagsTrack_ = _this.tech_.addTextTrack("metadata", "ad-cues"), _this.cueTagsTrack_.inBandMetadataTrackDispatchType = ""), _this.requestOptions_ = {

crates/swc_ecma_minifier/tests/fixture/next/33265/static/chunks/pages/index-cb36c1bf7f830e3c/output.js

@@ -948,9 +948,8 @@
                 function loadFunc() {
                     if (!aborted) {
                         clearTimeout(timeoutTimer);
-                        var status, response = failureResponse, err = null;
-                        return 0 !== (//IE8 CORS GET successful response doesn't have a status field, but body is fine
-                        status = options.useXDR && void 0 === xhr.status ? 200 : 1223 === xhr.status ? 204 : xhr.status) ? (response = {
+                        var status = options.useXDR && void 0 === xhr.status ? 200 : 1223 === xhr.status ? 204 : xhr.status, response = failureResponse, err = null;
+                        return 0 !== status ? (response = {
                             body: function() {
                                 // Chrome with requestType=blob throws errors arround when even testing access to responseText
                                 var body = void 0;
@@ -5791,7 +5790,7 @@
                         if ("INITIAL" === self1.state) {
                             // We can't start parsing until we have the first line.
                             if (!/\r\n|\n/.test(self1.buffer)) return this;
-                            var input, line, m = (line = collectNextLine()).match(/^WEBVTT([ \t].*)?$/);
+                            var input, line = collectNextLine(), m = line.match(/^WEBVTT([ \t].*)?$/);
                             if (!m || !m[0]) throw new ParsingError(ParsingError.Errors.BadSignature);
                             self1.state = "HEADER";
                         }

crates/swc_ecma_minifier/tests/fixture/next/react-ace/chunks/8a28b14e.d8fbda268ed281a1/output.js

@@ -5299,7 +5299,7 @@
                             }, this), folds;
                             range = location;
                         }
-                        for(var range, folds, outermostFolds = folds = this.getFoldsInRangeList(range); 1 == folds.length && 0 > Range.comparePoints(folds[0].start, range.start) && Range.comparePoints(folds[0].end, range.end) > 0;)this.expandFolds(folds), folds = this.getFoldsInRangeList(range);
+                        for(var range, folds = this.getFoldsInRangeList(range), outermostFolds = folds; 1 == folds.length && 0 > Range.comparePoints(folds[0].start, range.start) && Range.comparePoints(folds[0].end, range.end) > 0;)this.expandFolds(folds), folds = this.getFoldsInRangeList(range);
                         if (!1 != expandInner ? this.removeFolds(folds) : this.expandFolds(folds), outermostFolds.length) return outermostFolds;
                     }, this.isRowFolded = function(docRow, startFoldRow) {
                         return !!this.getFoldLine(docRow, startFoldRow);
@@ -10798,11 +10798,10 @@ margin: 0 10px;\
                         if (deltaY < 0 && this.session.getScrollTop() >= 1 - this.scrollMargin.top || deltaY > 0 && this.session.getScrollTop() + this.$size.scrollerHeight - this.layerConfig.maxHeight < -1 + this.scrollMargin.bottom || deltaX < 0 && this.session.getScrollLeft() >= 1 - this.scrollMargin.left || deltaX > 0 && this.session.getScrollLeft() + this.$size.scrollerWidth - this.layerConfig.width < -1 + this.scrollMargin.right) return !0;
                     }, this.pixelToScreenCoordinates = function(x, y) {
                         if (this.$hasCssTransforms) {
-                            canvasPos = {
+                            var canvasPos = {
                                 top: 0,
                                 left: 0
-                            };
-                            var canvasPos, p = this.$fontMetrics.transformCoordinates([
+                            }, p = this.$fontMetrics.transformCoordinates([
                                 x,
                                 y
                             ]);
@@ -10817,11 +10816,10 @@ margin: 0 10px;\
                         };
                     }, this.screenToTextCoordinates = function(x, y) {
                         if (this.$hasCssTransforms) {
-                            canvasPos = {
+                            var canvasPos = {
                                 top: 0,
                                 left: 0
-                            };
-                            var canvasPos, p = this.$fontMetrics.transformCoordinates([
+                            }, p = this.$fontMetrics.transformCoordinates([
                                 x,
                                 y
                             ]);