From 5ef7060098e231e1c31800f0ebcb19317bf0e077 Mon Sep 17 00:00:00 2001 From: "Alex Lam S.L" Date: Thu, 14 May 2020 18:09:54 +0100 Subject: fix corner case in `collapse_vars` (#3898) fixes #3897 --- lib/compress.js | 10 ++++++---- 1 file changed, 6 insertions(+), 4 deletions(-) (limited to 'lib/compress.js') diff --git a/lib/compress.js b/lib/compress.js index 93dbe063..36a04a70 100644 --- a/lib/compress.js +++ b/lib/compress.js @@ -1855,7 +1855,12 @@ merge(Compressor.prototype, { } function foldable(expr) { + var lhs_ids = Object.create(null); + var marker = new TreeWalker(function(node) { + if (node instanceof AST_SymbolRef) lhs_ids[node.definition().id] = true; + }); while (expr instanceof AST_Assign && expr.operator == "=") { + expr.left.walk(marker); expr = expr.right; } if (expr instanceof AST_SymbolRef) { @@ -1871,12 +1876,9 @@ merge(Compressor.prototype, { if (!(lhs instanceof AST_SymbolRef)) return false; if (!invariant(expr)) return false; var circular; - var def = lhs.definition(); expr.walk(new TreeWalker(function(node) { if (circular) return true; - if (node instanceof AST_SymbolRef && node.definition() === def) { - circular = true; - } + if (node instanceof AST_SymbolRef && lhs_ids[node.definition().id]) circular = true; })); return !circular && rhs_exact_match; -- cgit v1.2.3