diff options
| -rw-r--r-- | lib/compress.js | 51 | ||||
| -rw-r--r-- | test/compress/issue-1750.js | 25 |
2 files changed, 50 insertions, 26 deletions
diff --git a/lib/compress.js b/lib/compress.js index 1d9cd401..fc11840d 100644 --- a/lib/compress.js +++ b/lib/compress.js @@ -2537,49 +2537,39 @@ merge(Compressor.prototype, { var body = []; var default_branch; var exact_match; - var fallthrough; for (var i = 0, len = self.body.length; i < len && !exact_match; i++) { branch = self.body[i]; if (branch instanceof AST_Default) { - if (!default_branch) default_branch = branch; - else if (!fallthrough) { - extract_declarations_from_unreachable_code(compressor, branch, decl); - continue; + if (!default_branch) { + default_branch = branch; + } else { + eliminate_branch(branch); } } else if (value !== self.expression) { var exp = branch.expression.evaluate(compressor); if (exp === value) { exact_match = branch; if (default_branch) { - body.splice(body.indexOf(default_branch), 1); - extract_declarations_from_unreachable_code(compressor, default_branch, decl); + var default_index = body.indexOf(default_branch); + body.splice(default_index, 1); + eliminate_branch(default_branch, body[default_index - 1]); default_branch = null; } - } else if (exp !== branch.expression && !fallthrough) { - extract_declarations_from_unreachable_code(compressor, branch, decl); + } else if (exp !== branch.expression) { + eliminate_branch(branch); continue; } } if (aborts(branch)) { - if (body.length > 0 && !fallthrough) { - var prev = body[body.length - 1]; - if (prev.body.length == branch.body.length - && make_node(AST_BlockStatement, prev, prev).equivalent_to(make_node(AST_BlockStatement, branch, branch))) - prev.body = []; - } - body.push(branch); - fallthrough = false; - } else { - body.push(branch); - fallthrough = true; + var prev = body[body.length - 1]; + if (aborts(prev) && prev.body.length == branch.body.length + && make_node(AST_BlockStatement, prev, prev).equivalent_to(make_node(AST_BlockStatement, branch, branch))) { + prev.body = []; + } } + body.push(branch); } - for (; i < len && fallthrough; i++) { - branch = self.body[i]; - exact_match.body = exact_match.body.concat(branch.body); - fallthrough = !aborts(exact_match); - } - while (i < len) extract_declarations_from_unreachable_code(compressor, self.body[i++], decl); + while (i < len) eliminate_branch(self.body[i++]); if (body.length > 0) { body[0].body = decl.concat(body[0].body); } @@ -2612,6 +2602,15 @@ merge(Compressor.prototype, { if (!has_break) return make_node(AST_BlockStatement, self, body[0]).optimize(compressor); } return self; + + function eliminate_branch(branch, prev) { + if (!prev) prev = body[body.length - 1]; + if (prev && !aborts(prev)) { + prev.body = prev.body.concat(branch.body); + } else { + extract_declarations_from_unreachable_code(compressor, branch, decl); + } + } }); OPT(AST_Try, function(self, compressor){ diff --git a/test/compress/issue-1750.js b/test/compress/issue-1750.js new file mode 100644 index 00000000..53a78e65 --- /dev/null +++ b/test/compress/issue-1750.js @@ -0,0 +1,25 @@ +case_1: { + options = { + dead_code: true, + evaluate: true, + } + input: { + var a = 0, b = 1; + switch (true) { + case a, true: + default: + b = 2; + case true: + } + console.log(a, b); + } + expect: { + var a = 0, b = 1; + switch (true) { + case a, true: + b = 2; + } + console.log(a, b); + } + expect_stdout: "0 2" +} |