Memoise Decompile(0) on AST nodes

CLAUDE.md

@@ -129,6 +129,25 @@ empties the cache.
 Cache hits cost ~7% of a miss (0.002ms vs 0.032ms), worth roughly 30% of expression-parse time on
 a large file.
 
+### Decompile(0) is memoised — setters must invalidate
+
+`Decompile(int)` is declared on the `CFStatement` and `CFScriptStatement` interfaces, and both
+abstract `CFParsedStatement` bases implement it as a wrapper that caches the `indent == 0` result
+and delegates to `decompileImpl(int)`. **Concrete nodes override `decompileImpl`, not `Decompile`.**
+A non-zero indent is only reached from a parent already rendering itself, so it is not cached.
+
+`CFCase` and `CFCatchStatement` implement the interface directly rather than extending a base, so
+they still override `Decompile` and get no caching.
+
+The cached string is valid only while the node is unchanged. Nothing mutates a node after the
+visitor finishes building it — which is before any consumer can hold a reference — but **a setter
+that changes rendering must call `invalidateDecompiled()`**, or `Decompile(0)` keeps handing back
+the text from before the change. `setIsShortHand`, `setStatic`, `setModifier` and
+`setMemberOperator` are the kind of setter this applies to.
+
+Worth roughly 6% of a large CFLint scan (74% of `Decompile(0)` calls were repeats), and nothing on
+a small one, where DFA warm-up dominates — see below.
+
 ## Downstream: CFLint
 
 `cfmleditor/CFLint` is the main consumer. It declares the cfparser version **twice** — a

cfml.parsing/src/main/java/cfml/parsing/cfscript/CFAnonymousComponentExpression.java

@@ -40,7 +40,7 @@ public CFCompDeclStatement getComponentDeclaration() {
 	}
 
 	@Override
-	public String Decompile(int indent) {
+	protected String decompileImpl(int indent) {
 		return "new " + componentDeclaration.Decompile(0);
 	}
 

cfml.parsing/src/main/java/cfml/parsing/cfscript/CFAnonymousFunctionExpression.java

@@ -28,7 +28,7 @@ public byte getType() {
 	}
 
 	@Override
-	public String Decompile(int indent) {
+	protected String decompileImpl(int indent) {
 		return (funcDeclStatement.Decompile(0));
 	}
 

cfml.parsing/src/main/java/cfml/parsing/cfscript/CFArrayExpression.java

@@ -29,7 +29,7 @@ public void addElement(CFExpression _e) {
 	}
 
 	@Override
-	public String Decompile(int indent) {
+	protected String decompileImpl(int indent) {
 		if (elements.size() > 0) {
 			StringBuilder sb = new StringBuilder();
 			sb.append('[');

cfml.parsing/src/main/java/cfml/parsing/cfscript/CFAssignmentExpression.java

@@ -105,7 +105,7 @@ public void checkIndirectAssignments(String[] scriptSource) {
 	}
 
 	@Override
-	public String Decompile(int indent) {
+	protected String decompileImpl(int indent) {
 		StringBuilder sb = new StringBuilder();
 		if (left != null) {
 			sb.append(left.Decompile(indent));

cfml.parsing/src/main/java/cfml/parsing/cfscript/CFBinaryExpression.java

@@ -43,7 +43,7 @@ public byte getType() {
 	}
 
 	@Override
-	public String Decompile(int indent) {
+	protected String decompileImpl(int indent) {
 		String endChar = "";
 		if (_kind == CFSCRIPTLexer.LEFTBRACKET) {
 			endChar = "]";

cfml.parsing/src/main/java/cfml/parsing/cfscript/CFElvisExpression.java

@@ -12,7 +12,7 @@ public CFElvisExpression(Token t, CFExpression left, CFExpression right) {
 	}
 
 	@Override
-	public String Decompile(int indent) {
+	protected String decompileImpl(int indent) {
 		return "" + _left.Decompile(indent) + " " + operatorImage + " " + _right.Decompile(indent);
 	}
 

cfml.parsing/src/main/java/cfml/parsing/cfscript/CFFullVarExpression.java

@@ -65,7 +65,7 @@ public void addMember(CFExpression _right) {
 	}
 
 	@Override
-	public String Decompile(int indent) {
+	protected String decompileImpl(int indent) {
 		StringBuilder sb = new StringBuilder();
 		for (CFExpression expression : expressions) {
 			if (sb.length() > 0) {

cfml.parsing/src/main/java/cfml/parsing/cfscript/CFFunctionExpression.java

@@ -52,7 +52,7 @@ public boolean isUDF() {
 	}
 
 	@Override
-	public String Decompile(int indent) {
+	protected String decompileImpl(int indent) {
 		String s = nameId == null ? "" : nameId.Decompile(indent);
 		s += "(";
 

cfml.parsing/src/main/java/cfml/parsing/cfscript/CFIdentifier.java

@@ -53,7 +53,7 @@ public Token getToken() {
 	}
 
 	@Override
-	public String Decompile(int indent) {
+	protected String decompileImpl(int indent) {
 		return getFullName();
 	}
 

cfml.parsing/src/main/java/cfml/parsing/cfscript/CFJavaMethodExpression.java

@@ -56,7 +56,7 @@ public void setOnMethodMissing() {
 	}
 
 	@Override
-	public String Decompile(int indent) {
+	protected String decompileImpl(int indent) {
 		StringBuilder sb = new StringBuilder();
 		sb.append(name.Decompile(indent));
 		sb.append("(");

cfml.parsing/src/main/java/cfml/parsing/cfscript/CFLambdaExpression.java

@@ -57,7 +57,7 @@ public CFExpression getExpressionBody() {
 	}
 
 	@Override
-	public String Decompile(int indent) {
+	protected String decompileImpl(int indent) {
 		CFFuncDeclStatement declaration = getFuncDeclStatement();
 		StringBuilder sb = new StringBuilder();
 		sb.append("(");

cfml.parsing/src/main/java/cfml/parsing/cfscript/CFLiteral.java

@@ -60,7 +60,7 @@ public String getStringImage() {
 	}
 
 	@Override
-	public String Decompile(int indent) {
+	protected String decompileImpl(int indent) {
 		try {
 			if (CFSCRIPTLexer.STRING_LITERAL == kind && val != null) {
 				return "'" + val + "'";

cfml.parsing/src/main/java/cfml/parsing/cfscript/CFMember.java

@@ -34,7 +34,7 @@ public Token getToken() {
 	}
 
 	@Override
-	public String Decompile(int indent) {
+	protected String decompileImpl(int indent) {
 		return "[" + expression.Decompile(0) + "]";
 	}
 

cfml.parsing/src/main/java/cfml/parsing/cfscript/CFMultipartIdentifier.java

@@ -20,9 +20,9 @@ public CFMultipartIdentifier(CFIdentifier... identifiers) {
 	}
 
 	@Override
-	public String Decompile(int indent) {
+	protected String decompileImpl(int indent) {
 		StringBuffer sb = new StringBuffer();
-		sb.append(super.Decompile(indent));
+		sb.append(super.decompileImpl(indent));
 		for (int i = 1; i < ids.size(); i++) {
 			sb.append(".").append(ids.get(i).Decompile(0));
 		}

cfml.parsing/src/main/java/cfml/parsing/cfscript/CFNestedExpression.java

@@ -28,7 +28,7 @@ public byte getType() {
 	}
 
 	@Override
-	public String Decompile(int indent) {
+	protected String decompileImpl(int indent) {
 		StringBuilder sb = new StringBuilder();
 		sb.append('#');
 		sb.append(sub.Decompile(0));

cfml.parsing/src/main/java/cfml/parsing/cfscript/CFNewExpression.java

@@ -38,7 +38,7 @@ public CFNewExpression(Token _t, CFExpression _component, String _pathPrefix, Ar
 	}
 
 	@Override
-	public String Decompile(int indent) {
+	protected String decompileImpl(int indent) {
 		StringBuilder sb = new StringBuilder();
 		sb.append("new ");
 		if (pathPrefix != null) {

cfml.parsing/src/main/java/cfml/parsing/cfscript/CFParsedStatement.java

@@ -52,8 +52,40 @@ public void setToken(Token t) {
 		token = t;
 	}
 
+	/**
+	 * Decompile(0) is the form consumers ask for, and they ask repeatedly: a CFLint scan
+	 * runs every rule over every node and several of them decompile the same node, so a
+	 * 3,002-file scan made 1.25M calls of which 74% were repeats. Each one rebuilds the
+	 * whole subtree's text by concatenation, so the repeats are pure waste. Cache that
+	 * one form; a non-zero indent is only ever reached from a parent already rendering
+	 * itself, so it is not worth keying on.
+	 *
+	 * The cached string is only valid while the node is unchanged. Nothing mutates a node
+	 * after the visitor finishes building it, which is before any consumer can hold a
+	 * reference -- but a setter added later that changes rendering must call
+	 * invalidateDecompiled(), or it will hand back the text from before the change.
+	 */
 	@Override
-	public abstract String Decompile(int indent);
+	public String Decompile(int indent) {
+		if (indent != 0) {
+			return decompileImpl(indent);
+		}
+		String cached = decompiled0;
+		if (cached == null) {
+			cached = decompileImpl(0);
+			decompiled0 = cached;
+		}
+		return cached;
+	}
+
+	/** Drops the cached Decompile(0) text. Call from any setter that changes rendering. */
+	protected void invalidateDecompiled() {
+		decompiled0 = null;
+	}
+
+	private transient String decompiled0;
+
+	protected abstract String decompileImpl(int indent);
 
 	@Override
 	public void checkIndirectAssignments(String[] scriptSource) {

cfml.parsing/src/main/java/cfml/parsing/cfscript/CFSliceMember.java

@@ -47,7 +47,7 @@ public CFExpression getBy() {
 	}
 
 	@Override
-	public String Decompile(int indent) {
+	protected String decompileImpl(int indent) {
 		StringBuilder sb = new StringBuilder("[");
 		sb.append(decompileBound(getFrom()));
 		sb.append(":");

cfml.parsing/src/main/java/cfml/parsing/cfscript/CFStringExpression.java

@@ -23,7 +23,7 @@ public CFStringExpression(Token t) {
 	private static final long serialVersionUID = 233826913909000678L;
 
 	@Override
-	public String Decompile(int indent) {
+	protected String decompileImpl(int indent) {
 		StringBuilder sb = new StringBuilder();
 		sb.append("'");
 		for (CFExpression expression : subExpressions) {

cfml.parsing/src/main/java/cfml/parsing/cfscript/CFStructElementExpression.java

@@ -32,7 +32,7 @@ public String toString() {
 	}
 
 	@Override
-	public String Decompile(int indent) {
+	protected String decompileImpl(int indent) {
 		StringBuilder sb = new StringBuilder();
 		sb.append(key.Decompile(0));
 		sb.append(':');

cfml.parsing/src/main/java/cfml/parsing/cfscript/CFStructExpression.java

@@ -46,7 +46,7 @@ public void addElement(CFStructElementExpression _element) {
 	}
 
 	@Override
-	public String Decompile(int indent) {
+	protected String decompileImpl(int indent) {
 		StringBuilder sb = new StringBuilder();
 		sb.append(ordered ? '[' : '{');
 		if (elements.isEmpty() && emptyMarker != null) {

cfml.parsing/src/main/java/cfml/parsing/cfscript/CFTernaryExpression.java

@@ -39,7 +39,7 @@ public byte getType() {
 	}
 
 	@Override
-	public String Decompile(int indent) {
+	protected String decompileImpl(int indent) {
 		// String endChar = "";
 		// if (_kind == CFSCRIPTLexer.LEFTBRACKET) {
 		// endChar = "]";

cfml.parsing/src/main/java/cfml/parsing/cfscript/CFUnaryExpression.java

@@ -46,7 +46,7 @@ public boolean isPrefixop() {
 	}
 
 	@Override
-	public String Decompile(int indent) {
+	protected String decompileImpl(int indent) {
 		StringBuilder sb = new StringBuilder();
 
 		switch (kind) {

cfml.parsing/src/main/java/cfml/parsing/cfscript/CFVarDeclExpression.java

@@ -42,7 +42,7 @@ public CFVarDeclExpression(Token _t, CFExpression _var, CFExpression _init) {
 	}
 
 	@Override
-	public String Decompile(int indent) {
+	protected String decompileImpl(int indent) {
 		StringBuilder s = new StringBuilder(Indent(indent));
 		s.append(staticDecl ? "static " : finalDecl ? "final " : "var ");
 		s.append(var.Decompile(0));

cfml.parsing/src/main/java/cfml/parsing/cfscript/script/CFAbortStatement.java

@@ -25,7 +25,7 @@ public CFAbortStatement(org.antlr.v4.runtime.Token t, CFExpression _message) {
 	}
 
 	@Override
-	public String Decompile(int indent) {
+	protected String decompileImpl(int indent) {
 		if (message != null) {
 			return "abort \"" + message + "\"";
 		} else {

cfml.parsing/src/main/java/cfml/parsing/cfscript/script/CFAdminStatement.java

@@ -25,7 +25,7 @@ public CFAdminStatement(org.antlr.v4.runtime.Token t, Map<CFIdentifier, CFExpres
 	}
 
 	@Override
-	public String Decompile(int indent) {
+	protected String decompileImpl(int indent) {
 		StringBuilder sb = new StringBuilder();
 		sb.append("admin");
 		DecompileAttributes(sb);

cfml.parsing/src/main/java/cfml/parsing/cfscript/script/CFBreakStatement.java

@@ -13,7 +13,7 @@ public CFBreakStatement(org.antlr.v4.runtime.Token t) {
 	}
 
 	@Override
-	public String Decompile(int indent) {
+	protected String decompileImpl(int indent) {
 		return Indent(indent) + "break";
 	}
 

cfml.parsing/src/main/java/cfml/parsing/cfscript/script/CFCompDeclStatement.java

@@ -77,7 +77,7 @@ public CFStatementResult Exec(CFContext context) {
 	}
 
 	@Override
-	public String Decompile(int indent) {
+	protected String decompileImpl(int indent) {
 		StringBuilder sb = new StringBuilder();
 		sb.append(Indent(indent));
 		if (modifier != null) {

cfml.parsing/src/main/java/cfml/parsing/cfscript/script/CFCompoundStatement.java

@@ -49,7 +49,7 @@ public void checkIndirectAssignments(String[] scriptSource) {
 	}
 
 	@Override
-	public String Decompile(int indent) {
+	protected String decompileImpl(int indent) {
 		StringBuilder s = new StringBuilder();
 		s.append(Indent(indent));
 		s.append("{\n");

cfml.parsing/src/main/java/cfml/parsing/cfscript/script/CFContinueStatement.java

@@ -15,7 +15,7 @@ public CFContinueStatement(Token t) {
 	}
 
 	@Override
-	public String Decompile(int indent) {
+	protected String decompileImpl(int indent) {
 		return Indent(indent) + "continue";
 	}
 

cfml.parsing/src/main/java/cfml/parsing/cfscript/script/CFDoWhileStatement.java

@@ -33,7 +33,7 @@ public void checkIndirectAssignments(String[] scriptSource) {
 	}
 
 	@Override
-	public String Decompile(int indent) {
+	protected String decompileImpl(int indent) {
 		StringBuilder sb = new StringBuilder();
 		sb.append(Indent(indent));
 		sb.append("do");

cfml.parsing/src/main/java/cfml/parsing/cfscript/script/CFEmptyStatement.java

@@ -24,7 +24,7 @@ public CFEmptyStatement() {
 	}
 
 	@Override
-	public String Decompile(int indent) {
+	protected String decompileImpl(int indent) {
 		return Indent(indent) + ";";
 	}
 

cfml.parsing/src/main/java/cfml/parsing/cfscript/script/CFExitStatement.java

@@ -36,7 +36,7 @@ public CFExitStatement(org.antlr.v4.runtime.Token t, CFExpression _method) {
 	}
 
 	@Override
-	public String Decompile(int indent) {
+	protected String decompileImpl(int indent) {
 		if (methodArg != null) {
 			return "exit \"" + methodArg + "\"";
 		} else {

cfml.parsing/src/main/java/cfml/parsing/cfscript/script/CFExpressionStatement.java

@@ -16,7 +16,7 @@ public CFExpressionStatement(CFExpression _e) {
 	}
 
 	@Override
-	public String Decompile(int indent) {
+	protected String decompileImpl(int indent) {
 		return expression.Decompile(indent);
 	}
 

cfml.parsing/src/main/java/cfml/parsing/cfscript/script/CFForInStatement.java

@@ -27,7 +27,7 @@ public void checkIndirectAssignments(String[] scriptSource) {
 	}
 
 	@Override
-	public String Decompile(int indent) {
+	protected String decompileImpl(int indent) {
 		StringBuilder sb = new StringBuilder();
 		sb.append(Indent(indent));
 		sb.append("for( ");

cfml.parsing/src/main/java/cfml/parsing/cfscript/script/CFForStatement.java

@@ -29,7 +29,7 @@ public void checkIndirectAssignments(String[] scriptSource) {
 	}
 
 	@Override
-	public String Decompile(int indent) {
+	protected String decompileImpl(int indent) {
 		String s = Indent(indent) + "for(";
 		if (init != null) {
 			s += init.Decompile(indent);

cfml.parsing/src/main/java/cfml/parsing/cfscript/script/CFFuncDeclStatement.java

@@ -87,7 +87,7 @@ public CFStatementResult Exec(CFContext context) {
 	}
 
 	@Override
-	public String Decompile(int indent) {
+	protected String decompileImpl(int indent) {
 		StringBuilder sb = new StringBuilder();
 		sb.append(Indent(indent));