diff options
| -rw-r--r-- | lib/scope.js | 32 | ||||
| -rw-r--r-- | test/compress/dead-code.js | 49 |
2 files changed, 73 insertions, 8 deletions
diff --git a/lib/scope.js b/lib/scope.js index 22fb150d..144ae48e 100644 --- a/lib/scope.js +++ b/lib/scope.js @@ -358,13 +358,31 @@ AST_Symbol.DEFMETHOD("global", function(){ }); AST_Symbol.DEFMETHOD("has_const_pragma", function() { - var token = this.scope.body[0] && this.scope.body[0].start; - var comments = token && token.comments_before; - if (comments && comments.length > 0) { - var last = comments[comments.length - 1]; - return /@const/.test(last.value); - } - return false; + var symbol = this; + var symbol_has_pragma = false; + var pragma_found = false; + var found_symbol = false; + // Walk the current scope, looking for a comment with the @const pragma. + // If it exists, mark a bool that will remain true only for the next iteration. + // If the next iteration is this symbol, then we return true. + // Otherwise we stop descending and get out of here. + var tw = new TreeWalker(function(node, descend){ + // This is our symbol. Was the pragma before this? + if (node.name === symbol) { + found_symbol = true; + symbol_has_pragma = pragma_found; + } + + // Look for the /** @const */ pragma + var comments_before = node.start && node.start.comments_before; + var lastComment = comments_before && comments_before[comments_before.length - 1]; + pragma_found = lastComment && /@const/.test(lastComment.value); + + // no need to descend after finding our node + return found_symbol; + }); + this.scope.walk(tw); + return symbol_has_pragma; }) AST_Toplevel.DEFMETHOD("_default_mangler_options", function(options){ diff --git a/test/compress/dead-code.js b/test/compress/dead-code.js index f79b04de..8aad336c 100644 --- a/test/compress/dead-code.js +++ b/test/compress/dead-code.js @@ -97,6 +97,7 @@ dead_code_const_declaration: { evaluate : true
};
input: {
+ var unused;
const CONST_FOO = false;
if (CONST_FOO) {
console.log("unreachable");
@@ -105,6 +106,7 @@ dead_code_const_declaration: { }
}
expect: {
+ var unused;
const CONST_FOO = !1;
var moo;
function bar() {}
@@ -120,7 +122,8 @@ dead_code_const_annotation: { evaluate : true
};
input: {
- /** @const*/ var CONST_FOO_ANN = false;
+ var unused;
+ /** @const */ var CONST_FOO_ANN = false;
if (CONST_FOO_ANN) {
console.log("unreachable");
var moo;
@@ -128,8 +131,52 @@ dead_code_const_annotation: { }
}
expect: {
+ var unused;
var CONST_FOO_ANN = !1;
var moo;
function bar() {}
}
}
+
+dead_code_const_annotation_complex_scope: {
+ options = {
+ dead_code : true,
+ loops : true,
+ booleans : true,
+ conditionals : true,
+ evaluate : true
+ };
+ input: {
+ var unused_var;
+ /** @const */ var test = 'test';
+ /** @const */ var CONST_FOO_ANN = false;
+ var unused_var_2;
+ if (CONST_FOO_ANN) {
+ console.log("unreachable");
+ var moo;
+ function bar() {}
+ }
+ if (test === 'test') {
+ var beef = 'good';
+ /** @const */ var meat = 'beef';
+ var pork = 'bad';
+ if (meat === 'pork') {
+ console.log('also unreachable');
+ } else if (pork === 'good') {
+ console.log('reached, not const');
+ }
+ }
+ }
+ expect: {
+ var unused_var;
+ var test = 'test';
+ var CONST_FOO_ANN = !1;
+ var unused_var_2;
+ var moo;
+ function bar() {}
+ var beef = 'good';
+ var meat = 'beef';
+ var pork = 'bad';
+ 'good' === pork && console.log('reached, not const');
+ }
+}
|