From fdf2e8c5b079e3977b766c271d61a10cc3ab9947 Mon Sep 17 00:00:00 2001 From: "Alex Lam S.L" Date: Wed, 16 Sep 2020 23:35:22 +0100 Subject: [PATCH] enhance `collapse_vars` (#4117) --- lib/compress.js | 10 ++++++++-- test/compress/drop-unused.js | 3 +-- 2 files changed, 9 insertions(+), 4 deletions(-) diff --git a/lib/compress.js b/lib/compress.js index f19832e1..89d698da 100644 --- a/lib/compress.js +++ b/lib/compress.js @@ -1458,9 +1458,15 @@ merge(Compressor.prototype, { } function handle_custom_scan_order(node, tt) { + // Scan object only in a for-in statement + if (node instanceof AST_ForIn) { + node.object = node.object.transform(tt); + abort = true; + return node; + } // Skip (non-executed) functions if (node instanceof AST_Scope) return node; - // Scan case expressions first in a switch statement + // Scan first case expression only in a switch statement if (node instanceof AST_Switch) { node.expression = node.expression.transform(tt); for (var i = 0; !abort && i < node.body.length; i++) { @@ -1493,7 +1499,7 @@ merge(Compressor.prototype, { } if (node instanceof AST_Debugger) return true; if (node instanceof AST_Defun) return funarg && lhs.name === node.name.name; - if (node instanceof AST_IterationStatement) return !(node instanceof AST_For); + if (node instanceof AST_DWLoop) return true; if (node instanceof AST_LoopControl) return true; if (node instanceof AST_Try) return true; if (node instanceof AST_With) return true; diff --git a/test/compress/drop-unused.js b/test/compress/drop-unused.js index 96273a8d..3e2b54f2 100644 --- a/test/compress/drop-unused.js +++ b/test/compress/drop-unused.js @@ -2181,8 +2181,7 @@ issue_3515_1: { expect: { var c = 0; (function() { - this[c++] = 0; - for (var key20 in !0); + for (var key20 in !(this[c++] = 0)); })(); console.log(c); } -- 2.34.1