feat: mangle Infinity

CHANGELOG.md

@@ -1,5 +1,23 @@
 # Changelog
 
+## Unreleased
+
+* Minify Syntax `Infinity` to `1/0`
+
+ `--minify-syntax` will now minify the `Infinity` keyword to `1/0` which is less in bytes.
+
+ ```js
+ // Orginial code
+ const a = Infinity;
+
+ const b = 0 * Infinity;
+
+ // Output with "--mangle-syntax"
+ const a = 1/0;
+
+ const b = 0 * 1/0;
+ ```
+
 ## 0.12.9
 
 * Allow `this` with `--define` ([#1361](https:/evanw/esbuild/issues/1361))

internal/js_printer/js_printer.go

@@ -2129,18 +2129,23 @@ func (p *printer) printExpr(expr js_ast.Expr, level js_ast.L, flags printExprFla
  value := e.Value
  absValue := math.Abs(value)
 
+ infinity := "Infinity"
+ if p.options.MangleSyntax {
+ infinity = "1/0"
+ }
+
  if value != value {
  p.printSpaceBeforeIdentifier()
  p.print("NaN")
  } else if value == positiveInfinity {
  p.printSpaceBeforeIdentifier()
- p.print("Infinity")
+ p.print(infinity)
  } else if value == negativeInfinity {
  if level >= js_ast.LPrefix {
- p.print("(-Infinity)")
+ p.print("(-" + infinity + ")")
  } else {
  p.printSpaceBeforeOperator(js_ast.UnOpNeg)
- p.print("-Infinity")
+ p.print("-" + infinity)
  }
  } else {
  if !math.Signbit(value) {

internal/js_printer/js_printer_test.go

@@ -931,3 +931,14 @@ func TestAvoidSlashScript(t *testing.T) {
  expectPrintedMinify(t, "x = 1 < / script/.exec(y).length", "x=1</ script/.exec(y).length;")
  expectPrintedMinify(t, "x = 1 << / script/.exec(y).length", "x=1<</ script/.exec(y).length;")
 }
+
+func TestMangledENumber(t *testing.T) {
+ expectPrintedMangle(t, "x = Infinity", "x = 1/0;\n")
+ expectPrintedMangle(t, "x = -Infinity+2", "x = -1/0 + 2;\n")
+ expectPrintedMangle(t, "x = (-Infinity+2) / 3", "x = (-1/0 + 2) / 3;\n")
+ expectPrintedMangleMinify(t, "x = Infinity", "x=1/0;")
+ expectPrintedMangleMinify(t, "x = -Infinity+2", "x=-1/0+2;")
+ expectPrintedMangleMinify(t, "x = (-Infinity+2) / 3", "x=(-1/0+2)/3;")
+ expectPrintedMangleMinify(t, "1 + -Infinity", "1+-1/0;")
+ expectPrintedMangleMinify(t, "1 - -Infinity", "1- -1/0;")
+}