fix(es/minifier): Do not drop numbers incorrectly (#10211)

**Description:** Previously, numbers could be dropped wrongly if they were not zero-valued. It's unrealistic in real-world world source code, but it's still a bug.

Author: kdy1

crates/swc_ecma_minifier/src/compress/pure/misc.rs

@@ -749,7 +749,7 @@ impl Pure<'_> {
  arg.as_deref_mut().unwrap(),
  DropOpts {
  drop_global_refs_if_unused: true,
- drop_zero: true,
+ drop_number: true,
  drop_str_lit: true,
  ..Default::default()
  },
@@ -919,7 +919,7 @@ impl Pure<'_> {
  DropOpts {
  drop_global_refs_if_unused: true,
  drop_str_lit: true,
- drop_zero: true,
+ drop_number: true,
  },
  );
 
@@ -1091,10 +1091,11 @@ impl Pure<'_> {
  _ => (),
  }
 
- if self.options.unused {
+ if self.options.unused && opts.drop_number {
  if let Expr::Lit(Lit::Num(n)) = e {
  // Skip 0
  if n.value != 0.0 && n.value.classify() == FpCategory::Normal {
+ report_change!("Dropping a number");
  self.changed = true;
  *e = Invalid { span: DUMMY_SP }.into();
  return;
@@ -1133,7 +1134,7 @@ impl Pure<'_> {
  DropOpts {
  drop_str_lit: true,
  drop_global_refs_if_unused: true,
- drop_zero: true,
+ drop_number: true,
  ..opts
  },
  );
@@ -1206,7 +1207,8 @@ impl Pure<'_> {
  if self.options.unused || self.options.side_effects {
  match e {
  Expr::Lit(Lit::Num(n)) => {
- if n.value == 0.0 && opts.drop_zero {
+ if n.value == 0.0 && opts.drop_number {
+ report_change!("Dropping a zero number");
  self.changed = true;
  *e = Invalid { span: DUMMY_SP }.into();
  return;
@@ -1259,7 +1261,7 @@ impl Pure<'_> {
  self.ignore_return_value(
  &mut bin.left,
  DropOpts {
- drop_zero: true,
+ drop_number: true,
  drop_global_refs_if_unused: true,
  drop_str_lit: true,
  ..opts
@@ -1268,7 +1270,7 @@ impl Pure<'_> {
  self.ignore_return_value(
  &mut bin.right,
  DropOpts {
- drop_zero: true,
+ drop_number: true,
  drop_global_refs_if_unused: true,
  drop_str_lit: true,
  ..opts
@@ -1487,7 +1489,7 @@ impl Pure<'_> {
  &mut e.expr,
  DropOpts {
  drop_global_refs_if_unused: true,
- drop_zero: true,
+ drop_number: true,
  drop_str_lit: true,
  ..opts
  },
@@ -1518,7 +1520,7 @@ impl Pure<'_> {
  &mut expr,
  DropOpts {
  drop_str_lit: true,
- drop_zero: true,
+ drop_number: true,
  drop_global_refs_if_unused: true,
  ..opts
  },
@@ -1715,7 +1717,7 @@ pub(super) struct DropOpts {
  /// If true and `unused` option is enabled, references to global variables
  /// will be dropped, even if `side_effects` is false.
  pub drop_global_refs_if_unused: bool,
- pub drop_zero: bool,
+ pub drop_number: bool,
  pub drop_str_lit: bool,
 }
 

crates/swc_ecma_minifier/src/compress/pure/mod.rs

@@ -306,7 +306,7 @@ impl VisitMut for Pure<'_> {
  arg,
  DropOpts {
  drop_global_refs_if_unused: true,
- drop_zero: true,
+ drop_number: true,
  drop_str_lit: true,
  },
  );
@@ -537,7 +537,7 @@ impl VisitMut for Pure<'_> {
  self.ignore_return_value(
  &mut s.expr,
  DropOpts {
- drop_zero: true,
+ drop_number: true,
  drop_global_refs_if_unused: true,
  drop_str_lit: false,
  },
@@ -684,7 +684,7 @@ impl VisitMut for Pure<'_> {
  self.ignore_return_value(
  e,
  DropOpts {
- drop_zero: true,
+ drop_number: true,
  drop_global_refs_if_unused: true,
  drop_str_lit: true,
  ..Default::default()
@@ -788,7 +788,7 @@ impl VisitMut for Pure<'_> {
  self.ignore_return_value(
  e,
  DropOpts {
- drop_zero: can_drop_zero,
+ drop_number: can_drop_zero,
  drop_global_refs_if_unused: false,
  drop_str_lit: true,
  },