Minifying renamer for classes, methods and instance variables.

lib/compiler/implementation/js/printer.dart

 // Copyright (c) 2012, the Dart project authors.  Please see the AUTHORS file
 // for details. All rights reserved. Use of this source code is governed by a
 // BSD-style license that can be found in the LICENSE file.
 
 class Printer implements NodeVisitor {
   final bool shouldCompressOutput;
   leg.Compiler compiler;
   leg.CodeBuffer outBuffer;
   int indentLevel = 0;
   bool inForInit = false;
@@ skipping 930 matching lines @@
   static int nthLetter(int n) {
     return (n < 26) ? charCodes.$a + n : charCodes.$A + n - 26;
   }
 
   String declareName(String oldName) {
     const LETTERS = 52;
     const DIGITS = 10;
     if (maps.isEmpty) return oldName;
 
     String newName;
-    int n = nameNumber;
-    if (n < LETTERS) {
-      // Start naming variables a, b, c, ..., z, A, B, C, ..., Z.
-      newName = new String.fromCharCodes([nthLetter(n)]);
-    } else {
-      // Then name variables a0, a1, a2, ..., a9, b0, b1, ..., Z9, aa0, aa1, ...
-      // For all functions with fewer than 500 locals this is just as compact
-      // as using aa, ab, etc. but avoids clashes with keywords.
-      n -= LETTERS;
-      int digit = n % DIGITS;
-      n ~/= DIGITS;
-      int alphaChars = 1;
-      int nameSpaceSize = LETTERS;
-      // Find out whether we should use the 1-character namespace (size 52), the
-      // 2-character namespace (size 52*52), etc.
-      while (n >= nameSpaceSize) {
-        n -= nameSpaceSize;
-        alphaChars++;
-        nameSpaceSize *= LETTERS;
+    do {
+      int n = nameNumber;
+      if (n < LETTERS) {
+        // Start naming variables a, b, c, ..., z, A, B, C, ..., Z.
+        newName = new String.fromCharCodes([nthLetter(n)]);
+      } else {
+        // Then name variables a0, a1, ..., a9, b0, b1, ..., Z9, aa0, aa1, ...
+        // For all functions with fewer than 500 locals this is just as compact
+        // as using aa, ab, etc. but avoids clashes with keywords.
+        n -= LETTERS;
+        int digit = n % DIGITS;
+        n ~/= DIGITS;
+        int alphaChars = 1;
+        int nameSpaceSize = LETTERS;
+        // Find out whether we should use the 1-character namespace (size 52),
+        // the 2-character namespace (size 52*52), etc.
+        while (n >= nameSpaceSize) {
+          n -= nameSpaceSize;
+          alphaChars++;
+          nameSpaceSize *= LETTERS;
+        }
+        var codes = <int>[];
+        for (var i = 0; i < alphaChars; i++) {
+          nameSpaceSize ~/= LETTERS;
+          codes.add(nthLetter((n ~/ nameSpaceSize) % LETTERS));
+        }
+        codes.add(charCodes.$0 + digit);
+        newName = new String.fromCharCodes(codes);
       }
-      var codes = <int>[];
-      for (var i = 0; i < alphaChars; i++) {
-        nameSpaceSize ~/= LETTERS;
-        codes.add(nthLetter((n ~/ nameSpaceSize) % LETTERS));
-      }
-      codes.add(charCodes.$0 + digit);
-      newName = new String.fromCharCodes(codes);
-    }
-    assert(const RegExp(r'[a-zA-Z][a-zA-Z0-9]*').hasMatch(newName));
-    nameNumber++;
+      assert(const RegExp(r'[a-zA-Z][a-zA-Z0-9]*').hasMatch(newName));
+      nameNumber++;
+    } while (isReserved(newName));
     maps.last()[oldName] = newName;
     return newName;
   }
+
+  // We only have names here that are single-letter or end with a digit,
+  // since those are the ones we can generate.

[floitsch, 2012/10/25 08:42:40]

assert this.

[erikcorry, 2012/10/25 09:09:28]

Done.

+  bool isReserved(String name) {
+    return name == "I";  // Minified version of Isolate.

[floitsch, 2012/10/25 12:58:38]

Is there a way to get this set from the namer?

[erikcorry, 2012/12/06 09:38:07]

Done.

+  }
 }