fix(es/transforms/optimization): Fix dead_branch_remover (#2373)

swc_ecma_transforms_optimization: - `dead_branch_remover`: Fix handling of `switch(boolean)`.
swc-project · Oct 8, 2021 · 1f99c3a · 1f99c3a
1 parent b0ee954
commit 1f99c3a
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Showing 4 changed files with 11 additions and 2 deletions.
diff --git a/Cargo.lock b/Cargo.lock
diff --git a/ecmascript/transforms/optimization/Cargo.toml b/ecmascript/transforms/optimization/Cargo.toml
@@ -6,7 +6,7 @@ edition = "2018"
 license = "Apache-2.0/MIT"
 name = "swc_ecma_transforms_optimization"
 repository = "https://github.com/swc-project/swc.git"
-version = "0.49.0"
+version = "0.49.1"
 # See more keys and their definitions at https://doc.rust-lang.org/cargo/reference/manifest.html
 
 [dependencies]

diff --git a/ecmascript/transforms/optimization/src/simplify/branch/mod.rs b/ecmascript/transforms/optimization/src/simplify/branch/mod.rs
@@ -602,6 +602,10 @@ impl VisitMut for Remover {
                                         &Expr::Lit(Lit::Num(Number { value: test, .. })),
                                         &Expr::Lit(Lit::Num(Number { value: d, .. })),
                                     ) => (test - d).abs() < 1e-10,
+                                    (
+                                        &Expr::Lit(Lit::Bool(Bool { value: test, .. })),
+                                        &Expr::Lit(Lit::Bool(Bool { value: d, .. })),
+                                    ) => test == d,
                                     (&Expr::Lit(Lit::Null(..)), &Expr::Lit(Lit::Null(..))) => true,
                                     (&Expr::Ident(ref test), &Expr::Ident(ref d)) => {
                                         test.sym == d.sym && test.span.ctxt() == d.span.ctxt()

diff --git a/ecmascript/transforms/optimization/src/simplify/branch/tests.rs b/ecmascript/transforms/optimization/src/simplify/branch/tests.rs
@@ -540,6 +540,11 @@ fn test_optimize_switch_4() {
         "switch (1) {\ncase 1:\n  foo();\n  break;\ncase 2:\n  bar();\n  break;\n}",
         "foo();",
     );
+    test(
+        "switch (true) {\ncase true:\n  foo();\n  break;\ncase false:\n  bar();\n break; 
+            default: foobar(); break; \n}",
+        "foo();",
+    );
     test(
         "switch (1) {\ncase 1.1:\n  foo();\n  break;\ncase 2:\n  bar();\n  break;\n}",
         "",