fix #1998: keyword property name mangling

Author: evanw

CHANGELOG.md

@@ -1,5 +1,26 @@
 # Changelog
 
+## Unreleased
+
+* Fix property mangling and keyword properties ([#1998](https://github.com/evanw/esbuild/issues/1998))
+
+    Previously enabling property mangling with `--mangle-props=` failed to add a space before property names after a keyword. This bug has been fixed:
+
+    ```js
+    // Original code
+    class Foo {
+      static foo = {
+        get bar() {}
+      }
+    }
+
+    // Old output (with --minify --mangle-props=.)
+    class Foo{statics={gett(){}}}
+
+    // New output (with --minify --mangle-props=.)
+    class Foo{static s={get t(){}}}
+    ```
+
 ## 0.14.19
 
 * Special-case `const` inlining at the top of a scope ([#1317](https://github.com/evanw/esbuild/issues/1317), [#1981](https://github.com/evanw/esbuild/issues/1981))

internal/bundler/bundler_default_test.go

@@ -5419,6 +5419,27 @@ func TestManglePropsMinify(t *testing.T) {
 	})
 }
 
+func TestManglePropsKeywordPropertyMinify(t *testing.T) {
+	loader_suite.expectBundled(t, bundled{
+		files: map[string]string{
+			"/entry.js": `
+				class Foo {
+					static bar = { get baz() { return 123 } }
+				}
+			`,
+		},
+		entryPaths: []string{"/entry.js"},
+		options: config.Options{
+			Mode:              config.ModePassThrough,
+			AbsOutputDir:      "/out",
+			MangleProps:       regexp.MustCompile("."),
+			MinifyIdentifiers: true,
+			MinifySyntax:      true,
+			MinifyWhitespace:  true,
+		},
+	})
+}
+
 func TestManglePropsOptionalChain(t *testing.T) {
 	loader_suite.expectBundled(t, bundled{
 		files: map[string]string{

internal/bundler/snapshots/snapshots_loader.txt

@@ -597,6 +597,11 @@ export default [
   })
 ];
 
+================================================================================
+TestManglePropsKeywordPropertyMinify
+---------- /out/entry.js ----------
+class Foo{static t={get s(){return 123}}}
+
 ================================================================================
 TestManglePropsLoweredClassFields
 ---------- /out.js ----------

internal/js_printer/js_printer.go

@@ -988,6 +988,7 @@ func (p *printer) printProperty(item js_ast.Property) {
 	case *js_ast.EMangledProp:
 		p.addSourceMapping(item.Key.Loc)
 		if name := p.renamer.NameForSymbol(key.Ref); p.canPrintIdentifier(name) {
+			p.printSpaceBeforeIdentifier()
 			p.printIdentifier(name)
 
 			// Use a shorthand property if the names are the same

scripts/end-to-end-tests.js

@@ -2906,6 +2906,18 @@
     }),
   )
 
+  // Test minification of mangled properties (class and object) with a keyword before them
+  tests.push(
+    test(['in.js', '--outfile=node.js', '--minify', '--mangle-props=.'], {
+      'in.js': `
+        class Foo {
+          static bar = { get baz() { return 123 } }
+        }
+        if (Foo.bar.baz !== 123) throw 'fail'
+      `,
+    }),
+  )
+
   // Test minification of hoisted top-level symbols declared in nested scopes.
   // Previously this code was incorrectly transformed into this, which crashes:
   //