diff options
| -rw-r--r-- | lib/compress.js | 9 | ||||
| -rw-r--r-- | test/compress/comparisons.js | 30 |
2 files changed, 38 insertions, 1 deletions
diff --git a/lib/compress.js b/lib/compress.js index 4f942429..1b5d1a3a 100644 --- a/lib/compress.js +++ b/lib/compress.js @@ -6819,7 +6819,7 @@ merge(Compressor.prototype, { if ((self.left.is_string(compressor) && self.right.is_string(compressor)) || (self.left.is_number(compressor) && self.right.is_number(compressor)) || (self.left.is_boolean(compressor) && self.right.is_boolean(compressor)) || - self.left.equivalent_to(self.right)) { + can_self_compare(self.left) && self.left.equivalent_to(self.right)) { self.operator = self.operator.slice(0, 2); } // XXX: intentionally falling down to the next case @@ -7342,6 +7342,13 @@ merge(Compressor.prototype, { } return try_evaluate(compressor, self); + function can_self_compare(node) { + if (node instanceof AST_Dot) return can_self_compare(node.expression); + if (node instanceof AST_Sub) return can_self_compare(node.expression) && can_self_compare(node.property); + if (node instanceof AST_Symbol) return true; + return !node.has_side_effects(compressor); + } + function align(ref, op) { switch (ref) { case "-": diff --git a/test/compress/comparisons.js b/test/compress/comparisons.js index a4e0acc9..f93ccbe1 100644 --- a/test/compress/comparisons.js +++ b/test/compress/comparisons.js @@ -93,6 +93,36 @@ self_comparison_2: { expect_stdout: "false true" } +self_comparison_3: { + options = { + comparisons: true, + } + input: { + var a; + function f() { + var b = a; + a = null; + return b; + } + for (var i = 0; i < 2; i++) + console.log(f() === f()); + } + expect: { + var a; + function f() { + var b = a; + a = null; + return b; + } + for (var i = 0; i < 2; i++) + console.log(f() === f()); + } + expect_stdout: [ + "false", + "true", + ] +} + issue_2857_1: { options = { comparisons: true, |