fix(es/minifier): Always consider reassigned when inlining (#8168)

**Related issue:** - Closes #8161.
swc-project · Oct 23, 2023 · c26a225 · c26a225 · github-actions · Oct 23, 2023
1 parent 76ba243
commit c26a225
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diff --git a/crates/swc_ecma_minifier/src/compress/optimize/inline.rs b/crates/swc_ecma_minifier/src/compress/optimize/inline.rs
@@ -175,7 +175,7 @@ impl Optimizer<'_> {
             if is_inline_enabled
                 && usage.declared_count == 1
                 && usage.assign_count == 1
-                && (!usage.has_property_mutation || !usage.reassigned)
+                && !usage.reassigned
                 && match init {
                     Expr::Ident(Ident { sym, .. }) if &**sym == "eval" => false,
 

diff --git a/crates/swc_ecma_minifier/tests/fixture/issues/8161/input.js b/crates/swc_ecma_minifier/tests/fixture/issues/8161/input.js
@@ -0,0 +1,10 @@
+function run(flag, output = "a output") {
+    if (flag === "b") {
+        output = "b output";
+    }
+
+    console.log(output);
+}
+
+run("a");
+run("b");
diff --git a/crates/swc_ecma_minifier/tests/fixture/issues/8161/output.js b/crates/swc_ecma_minifier/tests/fixture/issues/8161/output.js
@@ -0,0 +1,4 @@
+function run(flag, output = "a output") {
+    "b" === flag && (output = "b output"), console.log(output);
+}
+run("a"), run("b");
Benchmark suite	Current: `c26a225`	Previous: `02d0613`	Ratio
`es/full/bugs-1`	`297591` ns/iter (`± 15876`)	`299007` ns/iter (`± 11909`)	`1.00`
`es/full/minify/libraries/antd`	`1418868535` ns/iter (`± 19210989`)	`1476291998` ns/iter (`± 18195232`)	`0.96`
`es/full/minify/libraries/d3`	`293681257` ns/iter (`± 947857`)	`302255474` ns/iter (`± 2958233`)	`0.97`
`es/full/minify/libraries/echarts`	`1125468958` ns/iter (`± 9821259`)	`1198367515` ns/iter (`± 24792959`)	`0.94`
`es/full/minify/libraries/jquery`	`89100441` ns/iter (`± 364942`)	`89791683` ns/iter (`± 336959`)	`0.99`
`es/full/minify/libraries/lodash`	`105560679` ns/iter (`± 366341`)	`104427358` ns/iter (`± 596845`)	`1.01`
`es/full/minify/libraries/moment`	`52471867` ns/iter (`± 79387`)	`52793536` ns/iter (`± 143385`)	`0.99`
`es/full/minify/libraries/react`	`18905262` ns/iter (`± 187544`)	`18784272` ns/iter (`± 166599`)	`1.01`
`es/full/minify/libraries/terser`	`233453084` ns/iter (`± 2025616`)	`232571476` ns/iter (`± 1922052`)	`1.00`
`es/full/minify/libraries/three`	`414839760` ns/iter (`± 2630087`)	`417149877` ns/iter (`± 2779734`)	`0.99`
`es/full/minify/libraries/typescript`	`2813695612` ns/iter (`± 10647686`)	`2863722850` ns/iter (`± 28173893`)	`0.98`
`es/full/minify/libraries/victory`	`609167287` ns/iter (`± 11730707`)	`608216738` ns/iter (`± 8250063`)	`1.00`
`es/full/minify/libraries/vue`	`127190271` ns/iter (`± 496240`)	`127630697` ns/iter (`± 471004`)	`1.00`
`es/full/codegen/es3`	`33369` ns/iter (`± 75`)	`33784` ns/iter (`± 96`)	`0.99`
`es/full/codegen/es5`	`33389` ns/iter (`± 281`)	`33980` ns/iter (`± 103`)	`0.98`
`es/full/codegen/es2015`	`33319` ns/iter (`± 90`)	`34079` ns/iter (`± 64`)	`0.98`
`es/full/codegen/es2016`	`33329` ns/iter (`± 102`)	`34052` ns/iter (`± 65`)	`0.98`
`es/full/codegen/es2017`	`33341` ns/iter (`± 113`)	`33976` ns/iter (`± 130`)	`0.98`
`es/full/codegen/es2018`	`33447` ns/iter (`± 128`)	`33869` ns/iter (`± 109`)	`0.99`
`es/full/codegen/es2019`	`33332` ns/iter (`± 53`)	`33849` ns/iter (`± 124`)	`0.98`
`es/full/codegen/es2020`	`33385` ns/iter (`± 89`)	`33801` ns/iter (`± 68`)	`0.99`
`es/full/all/es3`	`176851152` ns/iter (`± 1655263`)	`176853652` ns/iter (`± 792771`)	`1.00`
`es/full/all/es5`	`170574306` ns/iter (`± 1166089`)	`170318170` ns/iter (`± 4841250`)	`1.00`
`es/full/all/es2015`	`129207422` ns/iter (`± 1533857`)	`128311988` ns/iter (`± 654979`)	`1.01`
`es/full/all/es2016`	`128333484` ns/iter (`± 923435`)	`127836789` ns/iter (`± 885086`)	`1.00`
`es/full/all/es2017`	`127794822` ns/iter (`± 1129992`)	`127412193` ns/iter (`± 1287239`)	`1.00`
`es/full/all/es2018`	`125382985` ns/iter (`± 698973`)	`125094082` ns/iter (`± 1029271`)	`1.00`
`es/full/all/es2019`	`125013938` ns/iter (`± 1202019`)	`124469811` ns/iter (`± 562487`)	`1.00`
`es/full/all/es2020`	`121063117` ns/iter (`± 1272673`)	`120877524` ns/iter (`± 1838480`)	`1.00`
`es/full/parser`	`562074` ns/iter (`± 3452`)	`560613` ns/iter (`± 1262`)	`1.00`
`es/full/base/fixer`	`17785` ns/iter (`± 49`)	`17970` ns/iter (`± 153`)	`0.99`
`es/full/base/resolver_and_hygiene`	`82619` ns/iter (`± 623`)	`82474` ns/iter (`± 335`)	`1.00`