1 files changed, 169 insertions, 0 deletions
diff --git a/trunk/infrastructure/yuicompressor/src/com/yahoo/platform/yui/compressor/ScriptOrFnScope.java b/trunk/infrastructure/yuicompressor/src/com/yahoo/platform/yui/compressor/ScriptOrFnScope.java
new file mode 100644
index 0000000..c1a2e47
--- /dev/null
+++ b/trunk/infrastructure/yuicompressor/src/com/yahoo/platform/yui/compressor/ScriptOrFnScope.java
@@ -0,0 +1,169 @@
+/*
+ * YUI Compressor
+ * Author: Julien Lecomte <jlecomte@yahoo-inc.com>
+ * Copyright (c) 2007, Yahoo! Inc. All rights reserved.
+ * Code licensed under the BSD License:
+ *     http://developer.yahoo.net/yui/license.txt
+ */
+
+package com.yahoo.platform.yui.compressor;
+
+import java.util.ArrayList;
+import java.util.Enumeration;
+import java.util.Hashtable;
+
+class ScriptOrFnScope {
+
+    private int braceNesting;
+    private ScriptOrFnScope parentScope;
+    private ArrayList subScopes;
+    private Hashtable identifiers = new Hashtable();
+    private Hashtable hints = new Hashtable();
+    private boolean markedForMunging = true;
+    private int varcount = 0;
+
+    ScriptOrFnScope(int braceNesting, ScriptOrFnScope parentScope) {
+        this.braceNesting = braceNesting;
+        this.parentScope = parentScope;
+        this.subScopes = new ArrayList();
+        if (parentScope != null) {
+            parentScope.subScopes.add(this);
+        }
+    }
+
+    int getBraceNesting() {
+        return braceNesting;
+    }
+
+    ScriptOrFnScope getParentScope() {
+        return parentScope;
+    }
+
+    JavaScriptIdentifier declareIdentifier(String symbol) {
+        JavaScriptIdentifier identifier = (JavaScriptIdentifier) identifiers.get(symbol);
+        if (identifier == null) {
+            identifier = new JavaScriptIdentifier(symbol, this);
+            identifiers.put(symbol, identifier);
+        }
+        return identifier;
+    }
+
+    JavaScriptIdentifier getIdentifier(String symbol) {
+        return (JavaScriptIdentifier) identifiers.get(symbol);
+    }
+
+    void addHint(String variableName, String variableType) {
+        hints.put(variableName, variableType);
+    }
+
+    void preventMunging() {
+        if (parentScope != null) {
+            // The symbols in the global scope don't get munged,
+            // but the sub-scopes it contains do get munged.
+            markedForMunging = false;
+        }
+    }
+
+    private ArrayList getUsedSymbols() {
+        ArrayList result = new ArrayList();
+        Enumeration elements = identifiers.elements();
+        while (elements.hasMoreElements()) {
+            JavaScriptIdentifier identifier = (JavaScriptIdentifier) elements.nextElement();
+            String mungedValue = identifier.getMungedValue();
+            if (mungedValue == null) {
+                mungedValue = identifier.getValue();
+            }
+            result.add(mungedValue);
+        }
+        return result;
+    }
+
+    private ArrayList getAllUsedSymbols() {
+        ArrayList result = new ArrayList();
+        ScriptOrFnScope scope = this;
+        while (scope != null) {
+            result.addAll(scope.getUsedSymbols());
+            scope = scope.parentScope;
+        }
+        return result;
+    }
+
+    int incrementVarCount() {
+        varcount++;
+        return varcount;
+    }
+
+    void munge() {
+
+        if (!markedForMunging) {
+            // Stop right here if this scope was flagged as unsafe for munging.
+            return;
+        }
+
+        int pickFromSet = 1;
+
+        // Do not munge symbols in the global scope!
+        if (parentScope != null) {
+
+            ArrayList freeSymbols = new ArrayList();
+
+            freeSymbols.addAll(JavaScriptCompressor.ones);
+            freeSymbols.removeAll(getAllUsedSymbols());
+            if (freeSymbols.size() == 0) {
+                pickFromSet = 2;
+                freeSymbols.addAll(JavaScriptCompressor.twos);
+                freeSymbols.removeAll(getAllUsedSymbols());
+            }
+            if (freeSymbols.size() == 0) {
+                pickFromSet = 3;
+                freeSymbols.addAll(JavaScriptCompressor.threes);
+                freeSymbols.removeAll(getAllUsedSymbols());
+            }
+            if (freeSymbols.size() == 0) {
+                throw new IllegalStateException("The YUI Compressor ran out of symbols. Aborting...");
+            }
+
+	    // APPJET: sort identifiers by popularity
+	    JavaScriptIdentifier idArray[] = ((Hashtable<String,JavaScriptIdentifier>)identifiers).values().toArray(new JavaScriptIdentifier[0]);
+	    java.util.Arrays.sort(idArray, new java.util.Comparator<JavaScriptIdentifier>() {
+		    public int compare(JavaScriptIdentifier i1, JavaScriptIdentifier i2) {
+			return i2.getRefcount() - i1.getRefcount(); // positive if i2 is more popular, indicating i2 should come first
+		    }
+		});
+	    java.util.Iterator<JavaScriptIdentifier> elements = java.util.Arrays.asList(idArray).iterator();
+	    
+	    //Enumeration elements = identifiers.elements();
+            while (elements.hasNext()) {
+                if (freeSymbols.size() == 0) {
+                    pickFromSet++;
+                    if (pickFromSet == 2) {
+                        freeSymbols.addAll(JavaScriptCompressor.twos);
+                    } else if (pickFromSet == 3) {
+                        freeSymbols.addAll(JavaScriptCompressor.threes);
+                    } else {
+                        throw new IllegalStateException("The YUI Compressor ran out of symbols. Aborting...");
+                    }
+                    // It is essential to remove the symbols already used in
+                    // the containing scopes, or some of the variables declared
+                    // in the containing scopes will be redeclared, which can
+                    // lead to errors.
+                    freeSymbols.removeAll(getAllUsedSymbols());
+                }
+
+                String mungedValue;
+                JavaScriptIdentifier identifier = (JavaScriptIdentifier) elements.next();
+                if (identifier.isMarkedForMunging()) {
+                    mungedValue = (String) freeSymbols.remove(0);
+                } else {
+                    mungedValue = identifier.getValue();
+                }
+                identifier.setMungedValue(mungedValue);
+            }
+        }
+
+        for (int i = 0; i < subScopes.size(); i++) {
+            ScriptOrFnScope scope = (ScriptOrFnScope) subScopes.get(i);
+            scope.munge();
+        }
+    }
+}