aboutsummaryrefslogtreecommitdiff
diff options
context:
space:
mode:
authorAlex Lam S.L <alexlamsl@gmail.com>2020-01-28 07:33:11 +0800
committerGitHub <noreply@github.com>2020-01-28 07:33:11 +0800
commite9e76dcf040d5076b6046d7273c3509df106fb84 (patch)
treeafe9ded11df559969c75abcb106f6bc040f3a306
parent0dcedad2d5a6b670ecd5aef3cf18d5e511af6e91 (diff)
downloadtracifyjs-e9e76dcf040d5076b6046d7273c3509df106fb84.tar.gz
tracifyjs-e9e76dcf040d5076b6046d7273c3509df106fb84.zip
fix corner case in string concatenations (#3692)
- migrate de-facto compression to `conditionals` & `strings` fixes #3689
Diffstat
-rw-r--r--README.md2
-rw-r--r--lib/compress.js54
-rw-r--r--test/compress/arrays.js5
-rw-r--r--test/compress/concat-strings.js43
-rw-r--r--test/compress/dead-code.js1
-rw-r--r--test/compress/issue-269.js157
6 files changed, 164 insertions, 98 deletions
diff --git a/README.md b/README.md
index 1d5afa01..21dfabf9 100644
--- a/README.md
+++ b/README.md
@@ -736,6 +736,8 @@ If you're using the `X-SourceMap` header instead, you can just omit `sourceMap.u
annotation `/*@__PURE__*/` or `/*#__PURE__*/` immediately precedes the call. For
example: `/*@__PURE__*/foo();`
+- `strings` (default: `true`) -- compact string concatenations.
+
- `switches` (default: `true`) -- de-duplicate and remove unreachable `switch` branches
- `toplevel` (default: `false`) -- drop unreferenced functions (`"funcs"`) and/or
diff --git a/lib/compress.js b/lib/compress.js
index 4e967aef..e14d9d06 100644
--- a/lib/compress.js
+++ b/lib/compress.js
@@ -83,6 +83,7 @@ function Compressor(options, false_by_default) {
reduce_vars : !false_by_default,
sequences : !false_by_default,
side_effects : !false_by_default,
+ strings : !false_by_default,
switches : !false_by_default,
top_retain : null,
toplevel : !!(options && options["top_retain"]),
@@ -6188,6 +6189,18 @@ merge(Compressor.prototype, {
self.right = tmp;
}
}
+ function swap_chain() {
+ var rhs = self.right;
+ self.left = make_node(AST_Binary, self, {
+ operator: self.operator,
+ left: self.left,
+ right: rhs.left,
+ start: self.left.start,
+ end: rhs.left.end
+ });
+ self.right = rhs.right;
+ self.left = self.left.transform(compressor);
+ }
if (commutativeOperators[self.operator]
&& self.right.is_constant()
&& !self.left.is_constant()
@@ -6338,17 +6351,28 @@ merge(Compressor.prototype, {
case ">=": reverse("<="); break;
}
}
- if (self.operator == "+") {
+ // x && (y && z) => x && y && z
+ // x || (y || z) => x || y || z
+ if (compressor.option("conditionals")
+ && lazy_op[self.operator]
+ && self.right instanceof AST_Binary
+ && self.operator == self.right.operator) {
+ swap_chain();
+ }
+ if (compressor.option("strings") && self.operator == "+") {
+ // "foo" + 42 + "" => "foo" + 42
if (self.right instanceof AST_String
&& self.right.value == ""
&& self.left.is_string(compressor)) {
return self.left.optimize(compressor);
}
+ // "" + ("foo" + 42) => "foo" + 42
if (self.left instanceof AST_String
&& self.left.value == ""
&& self.right.is_string(compressor)) {
return self.right.optimize(compressor);
}
+ // "" + 42 + "foo" => 42 + "foo"
if (self.left instanceof AST_Binary
&& self.left.operator == "+"
&& self.left.left instanceof AST_String
@@ -6357,6 +6381,14 @@ merge(Compressor.prototype, {
self.left = self.left.right;
return self.optimize(compressor);
}
+ // "x" + (y + "z") => "x" + y + "z"
+ // x + ("y" + z) => x + "y" + z
+ if (self.right instanceof AST_Binary
+ && self.operator == self.right.operator
+ && (self.left.is_string(compressor) && self.right.is_string(compressor)
+ || self.right.left.is_string(compressor) && !self.right.right.has_side_effects(compressor))) {
+ swap_chain();
+ }
}
if (compressor.option("evaluate")) {
var associative = true;
@@ -6727,26 +6759,6 @@ merge(Compressor.prototype, {
return node.optimize(compressor);
}
}
- // x && (y && z) => x && y && z
- // x || (y || z) => x || y || z
- // x + ("y" + z) => x + "y" + z
- // "x" + (y + "z") => "x" + y + "z"
- if (self.right instanceof AST_Binary
- && self.right.operator == self.operator
- && (lazy_op[self.operator]
- || (self.operator == "+"
- && (self.right.left.is_string(compressor)
- || (self.left.is_string(compressor)
- && self.right.right.is_string(compressor))))))
- {
- self.left = make_node(AST_Binary, self.left, {
- operator : self.operator,
- left : self.left,
- right : self.right.left
- });
- self.right = self.right.right;
- return self.transform(compressor);
- }
return try_evaluate(compressor, self);
function align(ref, op) {
diff --git a/test/compress/arrays.js b/test/compress/arrays.js
index 497e96c4..9569c4fa 100644
--- a/test/compress/arrays.js
+++ b/test/compress/arrays.js
@@ -16,6 +16,7 @@ holes_and_undefined: {
constant_join: {
options = {
evaluate: true,
+ strings: true,
unsafe: true,
}
input: {
@@ -65,6 +66,7 @@ constant_join: {
constant_join_2: {
options = {
evaluate: true,
+ strings: true,
unsafe: true,
}
input: {
@@ -94,9 +96,11 @@ constant_join_2: {
constant_join_3: {
options = {
evaluate: true,
+ strings: true,
unsafe: true,
}
input: {
+ var foo, bar, baz;
var a = [ null ].join();
var b = [ , ].join();
var c = [ , 1, , 3 ].join();
@@ -111,6 +115,7 @@ constant_join_3: {
var l = [ foo, bar + "baz" ].join("");
}
expect: {
+ var foo, bar, baz;
var a = "";
var b = "";
var c = ",1,,3";
diff --git a/test/compress/concat-strings.js b/test/compress/concat-strings.js
index a9957d3d..5e8c512a 100644
--- a/test/compress/concat-strings.js
+++ b/test/compress/concat-strings.js
@@ -26,7 +26,9 @@ concat_1: {
}
concat_2: {
- options = {}
+ options = {
+ strings: true,
+ }
input: {
console.log(
1 + (2 + 3),
@@ -55,7 +57,9 @@ concat_2: {
}
concat_3: {
- options = {}
+ options = {
+ strings: true,
+ }
input: {
console.log(
1 + 2 + (3 + 4 + 5),
@@ -84,7 +88,9 @@ concat_3: {
}
concat_4: {
- options = {}
+ options = {
+ strings: true,
+ }
input: {
console.log(
1 + "2" + (3 + 4 + 5),
@@ -113,7 +119,9 @@ concat_4: {
}
concat_5: {
- options = {}
+ options = {
+ strings: true,
+ }
input: {
console.log(
"1" + 2 + (3 + 4 + 5),
@@ -142,7 +150,9 @@ concat_5: {
}
concat_6: {
- options = {}
+ options = {
+ strings: true,
+ }
input: {
console.log(
"1" + "2" + (3 + 4 + 5),
@@ -171,6 +181,9 @@ concat_6: {
}
concat_7: {
+ options = {
+ strings: true,
+ }
input: {
console.log(
"" + 1,
@@ -197,6 +210,9 @@ concat_7: {
}
concat_8: {
+ options = {
+ strings: true,
+ }
input: {
console.log(
1 + "",
@@ -221,3 +237,20 @@ concat_8: {
}
expect_stdout: true
}
+
+issue_3689: {
+ options = {
+ strings: true,
+ }
+ input: {
+ console.log(function(a) {
+ return a + ("" + (a[0] = 0));
+ }([]));
+ }
+ expect: {
+ console.log(function(a) {
+ return a + ("" + (a[0] = 0));
+ }([]));
+ }
+ expect_stdout: "00"
+}
diff --git a/test/compress/dead-code.js b/test/compress/dead-code.js
index 024d710b..344e1ff9 100644
--- a/test/compress/dead-code.js
+++ b/test/compress/dead-code.js
@@ -830,6 +830,7 @@ issue_3552: {
unreachable_assign: {
options = {
dead_code: true,
+ strings: true,
}
input: {
console.log(A = "P" + (A = "A" + (B = "S" + (A = B = "S"))), A, B);
diff --git a/test/compress/issue-269.js b/test/compress/issue-269.js
index 20b11b0a..2adc5017 100644
--- a/test/compress/issue-269.js
+++ b/test/compress/issue-269.js
@@ -1,98 +1,111 @@
issue_269_1: {
- options = {
+ options = {
unsafe: true,
}
- input: {
- f(
- String(x),
- Number(x),
- Boolean(x),
+ input: {
+ var x = {};
+ console.log(
+ String(x),
+ Number(x),
+ Boolean(x),
- String(),
- Number(),
- Boolean()
- );
- }
- expect: {
- f(
- x + '', +x, !!x,
- '', 0, false
- );
- }
+ String(),
+ Number(),
+ Boolean()
+ );
+ }
+ expect: {
+ var x = {};
+ console.log(
+ x + "", +x, !!x,
+ "", 0, false
+ );
+ }
+ expect_stdout: true
}
issue_269_dangers: {
- options = {
+ options = {
unsafe: true,
}
- input: {
- f(
- String(x, x),
- Number(x, x),
- Boolean(x, x)
- );
- }
- expect: {
- f(String(x, x), Number(x, x), Boolean(x, x));
- }
+ input: {
+ var x = {};
+ console.log(
+ String(x, x),
+ Number(x, x),
+ Boolean(x, x)
+ );
+ }
+ expect: {
+ var x = {};
+ console.log(String(x, x), Number(x, x), Boolean(x, x));
+ }
+ expect_stdout: true
}
issue_269_in_scope: {
- options = {
+ options = {
unsafe: true,
}
- input: {
- var String, Number, Boolean;
- f(
- String(x),
- Number(x, x),
- Boolean(x)
- );
- }
- expect: {
- var String, Number, Boolean;
- f(String(x), Number(x, x), Boolean(x));
- }
+ input: {
+ var String, Number, Boolean;
+ var x = {};
+ console.log(
+ String(x),
+ Number(x, x),
+ Boolean(x)
+ );
+ }
+ expect: {
+ var String, Number, Boolean;
+ var x = {};
+ console.log(String(x), Number(x, x), Boolean(x));
+ }
+ expect_stdout: true
}
strings_concat: {
- options = {
+ options = {
+ strings: true,
unsafe: true,
}
- input: {
- f(
- String(x + 'str'),
- String('str' + x)
- );
- }
- expect: {
- f(
- x + 'str',
- 'str' + x
- );
- }
+ input: {
+ var x = {};
+ console.log(
+ String(x + "str"),
+ String("str" + x)
+ );
+ }
+ expect: {
+ var x = {};
+ console.log(
+ x + "str",
+ "str" + x
+ );
+ }
+ expect_stdout: true
}
regexp: {
- options = {
+ options = {
evaluate: true,
unsafe: true,
}
- input: {
- RegExp("foo");
- RegExp("bar", "ig");
- RegExp(foo);
- RegExp("bar", ig);
- RegExp("should", "fail");
- }
- expect: {
- /foo/;
- /bar/ig;
- RegExp(foo);
- RegExp("bar", ig);
- RegExp("should", "fail");
- }
- expect_warnings: [
- 'WARN: Error converting RegExp("should","fail") [test/compress/issue-269.js:5,2]',
- ]
+ input: {
+ RegExp("foo");
+ RegExp("bar", "ig");
+ RegExp(foo);
+ RegExp("bar", ig);
+ RegExp("should", "fail");
+ }
+ expect: {
+ /foo/;
+ /bar/ig;
+ RegExp(foo);
+ RegExp("bar", ig);
+ RegExp("should", "fail");
+ }
+ expect_warnings: [
+ 'WARN: Error converting RegExp("should","fail") [test/compress/issue-269.js:5,8]',
+ ]
}
generated by cgit