com.google.javascript.jscomp.ProcessClosurePrimitives Maven / Gradle / Ivy
Show all versions of closure-compiler-unshaded Show documentation
/*
* Copyright 2006 The Closure Compiler Authors.
*
* Licensed under the Apache License, Version 2.0 (the "License");
* you may not use this file except in compliance with the License.
* You may obtain a copy of the License at
*
* http://www.apache.org/licenses/LICENSE-2.0
*
* Unless required by applicable law or agreed to in writing, software
* distributed under the License is distributed on an "AS IS" BASIS,
* WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
* See the License for the specific language governing permissions and
* limitations under the License.
*/
package com.google.javascript.jscomp;
import static com.google.common.base.Preconditions.checkNotNull;
import static com.google.javascript.jscomp.ClosurePrimitiveErrors.INVALID_CLOSURE_CALL_SCOPE_ERROR;
import static com.google.javascript.jscomp.ClosurePrimitiveErrors.NULL_ARGUMENT_ERROR;
import static com.google.javascript.jscomp.ClosurePrimitiveErrors.TOO_MANY_ARGUMENTS_ERROR;
import com.google.common.collect.ImmutableMap;
import com.google.common.collect.Iterables;
import com.google.javascript.jscomp.NodeTraversal.AbstractPostOrderCallback;
import com.google.javascript.jscomp.modules.ModuleMetadataMap.ModuleMetadata;
import com.google.javascript.rhino.IR;
import com.google.javascript.rhino.JSDocInfo;
import com.google.javascript.rhino.JSTypeExpression;
import com.google.javascript.rhino.Node;
import com.google.javascript.rhino.QualifiedName;
import com.google.javascript.rhino.Token;
import java.util.ArrayList;
import java.util.HashMap;
import java.util.HashSet;
import java.util.List;
import java.util.Map;
import java.util.NoSuchElementException;
import java.util.Set;
import org.jspecify.nullness.Nullable;
/**
* Performs some Closure-specific simplifications including rewriting goog.base, goog.addDependency.
*
* Records forwardDeclared names in the internal compiler state.
*/
class ProcessClosurePrimitives extends AbstractPostOrderCallback implements CompilerPass {
static final DiagnosticType EXPECTED_OBJECTLIT_ERROR = DiagnosticType.error(
"JSC_EXPECTED_OBJECTLIT_ERROR",
"method \"{0}\" expected an object literal argument");
static final DiagnosticType EXPECTED_STRING_ERROR =
DiagnosticType.error(
"JSC_EXPECTED_STRING_ERROR", "method \"{0}\" expected a string argument");
static final DiagnosticType INVALID_STYLE_ERROR = DiagnosticType.error(
"JSC_INVALID_CSS_NAME_MAP_STYLE_ERROR",
"Invalid CSS name map style {0}");
static final DiagnosticType WEAK_NAMESPACE_TYPE = DiagnosticType.warning(
"JSC_WEAK_NAMESPACE_TYPE",
"Provided symbol declared with type Object. This is rarely useful. "
+ "For more information see "
+ "https://github.com/google/closure-compiler/wiki/A-word-about-the-type-Object");
static final DiagnosticType CLASS_NAMESPACE_ERROR =
DiagnosticType.error(
"JSC_CLASS_NAMESPACE_ERROR",
"\"{0}\" cannot be both provided and declared as a class. Try var {0} = class '{'...'}'"
+ " (metadata {1})");
static final DiagnosticType FUNCTION_NAMESPACE_ERROR =
DiagnosticType.error(
"JSC_FUNCTION_NAMESPACE_ERROR",
"\"{0}\" cannot be both provided and declared as a function. (metadata {1})");
static final DiagnosticType INVALID_PROVIDE_ERROR = DiagnosticType.error(
"JSC_INVALID_PROVIDE_ERROR",
"\"{0}\" is not a valid {1} qualified name");
static final DiagnosticType NON_STRING_PASSED_TO_SET_CSS_NAME_MAPPING_ERROR =
DiagnosticType.error(
"JSC_NON_STRING_PASSED_TO_SET_CSS_NAME_MAPPING_ERROR",
"goog.setCssNameMapping only takes an object literal with string values");
static final DiagnosticType INVALID_CSS_RENAMING_MAP = DiagnosticType.warning(
"INVALID_CSS_RENAMING_MAP",
"Invalid entries in css renaming map: {0}");
static final DiagnosticType BASE_CLASS_ERROR = DiagnosticType.error(
"JSC_BASE_CLASS_ERROR",
"incorrect use of {0}.base: {1}");
static final DiagnosticType INVALID_FORWARD_DECLARE =
DiagnosticType.error("JSC_INVALID_FORWARD_DECLARE", "Malformed goog.forwardDeclare");
static final DiagnosticType CLOSURE_CALL_CANNOT_BE_ALIASED_ERROR =
DiagnosticType.error(
"JSC_CLOSURE_CALL_CANNOT_BE_ALIASED_ERROR",
"Closure primitive method {0} may not be aliased");
static final DiagnosticType CLOSURE_CALL_CANNOT_BE_ALIASED_OUTSIDE_MODULE_ERROR =
DiagnosticType.error(
"JSC_CLOSURE_CALL_CANNOT_BE_ALIASED_ERROR",
"Closure primitive method {0} may not be aliased outside a module (ES "
+ "module, CommonJS module, or goog.module)");
static final DiagnosticType INVALID_RENAME_FUNCTION =
DiagnosticType.error("JSC_INVALID_RENAME_FUNCTION", "{0} call is invalid: {1}");
/** The root Closure namespace */
static final String GOOG = "goog";
private static final QualifiedName GOOG_INHERITS = QualifiedName.of("goog.inherits");
private final AbstractCompiler compiler;
private final Set knownClosureSubclasses = new HashSet<>();
private final Set exportedVariables = new HashSet<>();
private final ImmutableMap closureModules;
ProcessClosurePrimitives(AbstractCompiler compiler) {
this.compiler = compiler;
this.closureModules =
checkNotNull(compiler.getModuleMetadataMap(), "Need to run GatherModuleMetadata")
.getModulesByGoogNamespace();
}
Set getExportedVariableNames() {
return exportedVariables;
}
@Override
public void process(Node externs, Node root) {
// Replace and validate other Closure primitives
NodeTraversal.traverseRoots(compiler, this, externs, root);
}
@Override
public void visit(NodeTraversal t, Node n, Node parent) {
switch (n.getToken()) {
case CALL:
{
this.checkGoogFunctions(t, n);
this.maybeProcessClassBaseCall(n);
this.checkPropertyRenameCall(n);
}
break;
case FUNCTION:
case CLASS:
if (!t.inGlobalHoistScope() || n.isFromExterns()) {
return;
}
if (!NodeUtil.isFunctionDeclaration(n) && !NodeUtil.isClassDeclaration(n)) {
return;
}
String name = n.getFirstChild().getString();
ModuleMetadata pn = this.closureModules.get(name);
if (pn != null && pn.isGoogProvide()) {
compiler.report(
JSError.make(
n,
n.isClass() ? CLASS_NAMESPACE_ERROR : FUNCTION_NAMESPACE_ERROR,
name,
pn.toString()));
}
break;
case EXPR_RESULT:
if (!n.getFirstChild().isAssign() || !n.getFirstFirstChild().isQualifiedName()) {
break;
}
String lhs = n.getFirstFirstChild().getQualifiedName();
checkPossibleGoogProvideInit(lhs, n.getFirstChild().getJSDocInfo(), n);
break;
case VAR:
case CONST:
case LET:
if (!n.getFirstChild().isName()) {
break;
}
checkPossibleGoogProvideInit(n.getFirstChild().getString(), n.getJSDocInfo(), n);
break;
default:
break;
}
}
private void checkPossibleGoogProvideInit(
String namespace, @Nullable JSDocInfo info, Node definition) {
if (info == null || definition.isFromExterns()) {
return;
}
ModuleMetadata metadata = this.closureModules.get(namespace);
if (metadata == null || !metadata.isGoogProvide()) {
return;
}
// Validate that the namespace is not declared as a generic object type.
JSTypeExpression expr = info.getType();
if (expr == null) {
return;
}
Node n = expr.getRoot();
if (n.getToken() == Token.BANG) {
n = n.getFirstChild();
}
if (n.isStringLit()
&& !n.hasChildren() // templated object types are ok.
&& n.getString().equals("Object")) {
compiler.report(JSError.make(definition, WEAK_NAMESPACE_TYPE));
}
}
private void checkGoogFunctions(NodeTraversal t, Node call) {
Node callee = call.getFirstChild();
if (!callee.isGetProp()) {
return;
}
Node receiver = callee.getFirstChild();
if (!receiver.isName() || !receiver.getString().equals(GOOG)) {
return;
}
// For the sake of simplicity, we report code changes
// when we see a provides/requires, and don't worry about
// reporting the change when we actually do the replacement.
String methodName = callee.getString();
Node arg = callee.getNext();
switch (methodName) {
case "inherits":
// Note: inherits is allowed in local scope
processInheritsCall(call);
break;
case "exportSymbol":
// Note: exportSymbol is allowed in local scope
if (arg.isStringLit()) {
String argString = arg.getString();
int dot = argString.indexOf('.');
if (dot == -1) {
exportedVariables.add(argString);
} else {
exportedVariables.add(argString.substring(0, dot));
}
}
break;
case "addDependency":
if (validateUnaliasablePrimitiveCall(t, call, methodName)) {
processAddDependency(call);
}
break;
case "setCssNameMapping":
processSetCssNameMapping(call, call.getParent());
break;
case "forwardDeclare":
if (validatePrimitiveCallWithMessage(
t,
call,
methodName,
ProcessClosurePrimitives.CLOSURE_CALL_CANNOT_BE_ALIASED_OUTSIDE_MODULE_ERROR)) {
processForwardDeclare(call);
}
break;
default: // fall out
}
}
/**
* Verifies that a) the call is in the top level of a file and b) the return value is unused
*
* This method is for primitives that never return a value.
*/
private boolean validateUnaliasablePrimitiveCall(NodeTraversal t, Node n, String methodName) {
return validatePrimitiveCallWithMessage(t, n, methodName, CLOSURE_CALL_CANNOT_BE_ALIASED_ERROR);
}
/**
* @param methodName list of primitive types classed together with this one
* @param invalidAliasingError which DiagnosticType to emit if this call is aliased. this depends
* on whether the primitive is sometimes aliasiable in a module or never aliasable.
*/
private boolean validatePrimitiveCallWithMessage(
NodeTraversal t, Node n, String methodName, DiagnosticType invalidAliasingError) {
// Ignore invalid primitives if we didn't strip module sugar.
if (compiler.getOptions().shouldPreserveGoogModule()) {
return true;
}
if (!t.inGlobalHoistScope() && !t.inModuleScope()) {
compiler.report(JSError.make(n, INVALID_CLOSURE_CALL_SCOPE_ERROR));
return false;
} else if (!n.getParent().isExprResult() && !t.inModuleScope()) {
// If the call is in the global hoist scope, but the result is used
compiler.report(JSError.make(n, invalidAliasingError, GOOG + "." + methodName));
return false;
}
return true;
}
private void maybeProcessClassBaseCall(Node n) {
// Two things must hold for every base call:
// 1) We must be calling it on "this".
// 2) We must be calling it on a prototype method of the same name as
// the one we're in, OR we must be calling it from a constructor.
// If both of those things are true, then we can rewrite:
//
// function Foo() {
// Foo.base(this);
// }
// goog.inherits(Foo, BaseFoo);
// Foo.prototype.bar = function() {
// Foo.base(this, 'bar', 1);
// };
//
// as the easy-to-optimize:
//
// function Foo() {
// BaseFoo.call(this);
// }
// goog.inherits(Foo, BaseFoo);
// Foo.prototype.bar = function() {
// Foo.superClass_.bar.call(this, 1);
// };
//
// Most of the logic here is just to make sure the AST's
// structure is what we expect it to be.
Node callTarget = n.getFirstChild();
if (!callTarget.isGetProp() || !callTarget.getString().equals("base")) {
return;
}
Node baseContainerNode = callTarget.getFirstChild();
if (!baseContainerNode.isUnscopedQualifiedName()) {
// Some unknown "base" method.
return;
}
String baseContainer = callTarget.getFirstChild().getQualifiedName();
Node enclosingFnNameNode = getEnclosingDeclNameNode(n);
if (enclosingFnNameNode == null || !enclosingFnNameNode.isUnscopedQualifiedName()) {
// some unknown container method or a MEMBER_FUNCTION_DEF.
if (knownClosureSubclasses.contains(baseContainer)) {
reportBadBaseMethodUse(n, baseContainer, "Could not find enclosing method.");
} else if (baseUsedInClass(n)) {
Node clazz = NodeUtil.getEnclosingClass(n);
// TODO(lharker): this check ignores class expressions like "foo.Bar = class extends X {}"
if ((clazz.getFirstChild().isName()
&& clazz.getFirstChild().getString().equals(baseContainer))
|| (clazz.getSecondChild().isName()
&& clazz.getSecondChild().getString().equals(baseContainer))) {
reportBadBaseMethodUse(
n,
clazz.getFirstChild().getString(),
"base method is not allowed in ES6 class. Use super instead.");
}
}
return;
}
if (baseUsedInClass(n)) {
Node clazz = NodeUtil.getEnclosingClass(n);
String name = NodeUtil.getBestLValueName(clazz);
reportBadBaseMethodUse(
n, name, "base method is not allowed in ES6 class. Use super instead.");
return;
}
String enclosingQname = enclosingFnNameNode.getQualifiedName();
if (!enclosingQname.contains(".prototype.")) {
rewriteBaseCallInConstructor(enclosingQname, baseContainer, n, enclosingFnNameNode);
} else {
rewriteBaseCallInMethod(enclosingQname, baseContainer, n, enclosingFnNameNode);
}
}
private void rewriteBaseCallInConstructor(
String enclosingQname, String baseContainer, Node n, Node enclosingFnNameNode) {
// Check if this is some other "base" method.
if (!enclosingQname.equals(baseContainer)) {
// Report misuse of "base" methods from other known classes.
if (knownClosureSubclasses.contains(baseContainer)) {
reportBadBaseMethodUse(
n, baseContainer, "Must be used within " + baseContainer + " methods");
}
return;
}
// Determine if this is a class with a "base" method created by
// goog.inherits.
Node enclosingParent = enclosingFnNameNode.getParent();
Node baseClassNode =
findGoogInheritsCall(
enclosingParent.isAssign() ? enclosingParent.getParent() : enclosingParent);
if (baseClassNode == null) {
// If there is no "goog.inherits", this might be some other "base" method.
return;
}
// This is the expected method, validate its parameters.
Node callee = n.getFirstChild();
Node thisArg = callee.getNext();
if (thisArg == null || !thisArg.isThis()) {
reportBadBaseMethodUse(n, baseContainer, "First argument must be 'this'.");
return;
}
// Handle methods.
Node methodNameNode = thisArg.getNext();
if (methodNameNode == null
|| !methodNameNode.isStringLit()
|| !methodNameNode.getString().equals("constructor")) {
reportBadBaseMethodUse(n, baseContainer, "Second argument must be 'constructor'.");
return;
}
// We're good to go.
callee.replaceWith(
NodeUtil.newQName(
compiler,
baseClassNode.getQualifiedName() + ".call",
callee,
enclosingQname + ".base"));
methodNameNode.detach();
compiler.reportChangeToEnclosingScope(n);
}
private void rewriteBaseCallInMethod(
String enclosingQname, String baseContainer, Node n, Node enclosingFnNameNode) {
if (!knownClosureSubclasses.contains(baseContainer)) {
// Can't determine if this is a known "class" that has a known "base" method.
return;
}
boolean misuseOfBase =
!enclosingFnNameNode.getFirstFirstChild().matchesQualifiedName(baseContainer);
if (misuseOfBase) {
// Report misuse of "base" methods from other known classes.
reportBadBaseMethodUse(n, baseContainer, "Must be used within " + baseContainer + " methods");
return;
}
// The super class is known.
Node callee = n.getFirstChild();
Node thisArg = callee.getNext();
if (thisArg == null || !thisArg.isThis()) {
reportBadBaseMethodUse(n, baseContainer, "First argument must be 'this'.");
return;
}
// Handle methods.
Node methodNameNode = thisArg.getNext();
if (methodNameNode == null || !methodNameNode.isStringLit()) {
reportBadBaseMethodUse(n, baseContainer, "Second argument must name a method.");
return;
}
String methodName = methodNameNode.getString();
String ending = ".prototype." + methodName;
if (enclosingQname == null || !enclosingQname.endsWith(ending)) {
reportBadBaseMethodUse(n, baseContainer, "Enclosing method does not match " + methodName);
return;
}
// We're good to go.
Node className = enclosingFnNameNode.getFirstFirstChild();
callee.replaceWith(
NodeUtil.newQName(
compiler,
className.getQualifiedName() + ".superClass_." + methodName + ".call",
callee,
enclosingQname + ".base"));
methodNameNode.detach();
compiler.reportChangeToEnclosingScope(n);
}
private static Node findGoogInheritsCall(Node ctorDeclarationNode) {
Node maybeInheritsExpr = ctorDeclarationNode.getNext();
while (maybeInheritsExpr != null
&& (maybeInheritsExpr.isEmpty() || NodeUtil.isExprAssign(maybeInheritsExpr))) {
// Skip empty nodes (e.g. those created by an unnecessary semicolon) and potential aliases,
// e.g. "exports = Ctor;" in a goog.module.
maybeInheritsExpr = maybeInheritsExpr.getNext();
}
Node baseClassNode = null;
if (maybeInheritsExpr != null && NodeUtil.isExprCall(maybeInheritsExpr)) {
Node callNode = maybeInheritsExpr.getFirstChild();
if (GOOG_INHERITS.matches(callNode.getFirstChild())
&& callNode.getLastChild().isQualifiedName()) {
baseClassNode = callNode.getLastChild();
}
}
return baseClassNode;
}
/**
* Processes the goog.inherits call.
*/
private void processInheritsCall(Node n) {
if (n.hasXChildren(3)) {
Node subClass = n.getSecondChild();
Node superClass = subClass.getNext();
if (subClass.isUnscopedQualifiedName() && superClass.isUnscopedQualifiedName()) {
knownClosureSubclasses.add(subClass.getQualifiedName());
}
}
}
/**
* Returns the qualified name node of the function whose scope we're in, or null if it cannot be
* found.
*/
private static @Nullable Node getEnclosingDeclNameNode(Node n) {
Node fn = NodeUtil.getEnclosingFunction(n);
return fn == null ? null : NodeUtil.getNameNode(fn);
}
/** Verify if goog.base call is used in a class */
private static boolean baseUsedInClass(Node n) {
for (Node curr = n; curr != null; curr = curr.getParent()){
if (curr.isClassMembers()) {
return true;
}
}
return false;
}
/** Reports an incorrect use of super-method calling. */
private void reportBadBaseMethodUse(Node n, String className, String extraMessage) {
compiler.report(JSError.make(n, BASE_CLASS_ERROR, className, extraMessage));
}
/**
* Processes a call to goog.setCssNameMapping(). Either the argument to goog.setCssNameMapping()
* is valid, in which case it will be used to create a CssRenamingMap for the compiler of this
* CompilerPass, or it is invalid and a JSCompiler error will be reported.
*
* @see #visit(NodeTraversal, Node, Node)
*/
private void processSetCssNameMapping(Node n, Node parent) {
Node left = n.getFirstChild();
Node arg = left.getNext();
if (verifySetCssNameMapping(left, arg)) {
// Translate OBJECTLIT into SubstitutionMap. All keys and
// values must be strings, or an error will be thrown.
final Map cssNames = new HashMap<>();
for (Node key = arg.getFirstChild(); key != null;
key = key.getNext()) {
Node value = key.getFirstChild();
if (!key.isStringKey() || value == null || !value.isStringLit()) {
compiler.report(JSError.make(n, NON_STRING_PASSED_TO_SET_CSS_NAME_MAPPING_ERROR));
return;
}
cssNames.put(key.getString(), value.getString());
}
String styleStr = "BY_PART";
if (arg.getNext() != null) {
styleStr = arg.getNext().getString();
}
final CssRenamingMap.Style style;
try {
style = CssRenamingMap.Style.valueOf(styleStr);
} catch (IllegalArgumentException e) {
compiler.report(JSError.make(n, INVALID_STYLE_ERROR, styleStr));
return;
}
if (style == CssRenamingMap.Style.BY_PART) {
// Make sure that no keys contain -'s
List errors = new ArrayList<>();
for (String key : cssNames.keySet()) {
if (key.contains("-")) {
errors.add(key);
}
}
if (!errors.isEmpty()) {
compiler.report(JSError.make(n, INVALID_CSS_RENAMING_MAP, errors.toString()));
}
} else if (style == CssRenamingMap.Style.BY_WHOLE) {
// Verifying things is a lot trickier here. We just do a quick
// n^2 check over the map which makes sure that if "a-b" in
// the map, then map(a-b) = map(a)-map(b).
// To speed things up, only consider cases where len(b) <= 10
List errors = new ArrayList<>();
for (Map.Entry b : cssNames.entrySet()) {
if (b.getKey().length() > 10) {
continue;
}
for (Map.Entry a : cssNames.entrySet()) {
String combined = cssNames.get(a.getKey() + "-" + b.getKey());
if (combined != null && !combined.equals(a.getValue() + "-" + b.getValue())) {
errors.add("map(" + a.getKey() + "-" + b.getKey() + ") != map("
+ a.getKey() + ")-map(" + b.getKey() + ")");
}
}
}
if (!errors.isEmpty()) {
compiler.report(JSError.make(n, INVALID_CSS_RENAMING_MAP, errors.toString()));
}
}
CssRenamingMap cssRenamingMap = new CssRenamingMap() {
@Override
public String get(String value) {
if (cssNames.containsKey(value)) {
return cssNames.get(value);
} else {
return value;
}
}
@Override
public CssRenamingMap.Style getStyle() {
return style;
}
};
compiler.setCssRenamingMap(cssRenamingMap);
compiler.reportChangeToEnclosingScope(parent);
parent.detach();
}
}
/** Process a goog.addDependency() call and record any forward declarations. */
private void processAddDependency(Node n) {
CodingConvention convention = compiler.getCodingConvention();
List typeDecls =
convention.identifyTypeDeclarationCall(n);
// TODO(nnaze): Use of addDependency() should someday cause a warning
// as we migrate users to explicit goog.forwardDeclare() calls.
if (typeDecls != null) {
for (String typeDecl : typeDecls) {
compiler.forwardDeclareType(typeDecl);
}
}
// We can't modify parent, so just create a node that will
// get compiled out.
Node emptyNode = IR.number(0);
n.replaceWith(emptyNode);
compiler.reportChangeToEnclosingScope(emptyNode);
}
/** Process a goog.forwardDeclare() call and record the specified forward declaration. */
private void processForwardDeclare(Node n) {
if (!n.getParent().isExprResult()) {
// Ignore "const Foo = goog.forwardDeclare('my.Foo');". It's legal but does not actually
// forward declare the type 'my.Foo'.
return;
}
CodingConvention convention = compiler.getCodingConvention();
String typeDeclaration = null;
try {
typeDeclaration = Iterables.getOnlyElement(
convention.identifyTypeDeclarationCall(n));
} catch (NullPointerException | NoSuchElementException | IllegalArgumentException e) {
compiler.report(
JSError.make(
n,
INVALID_FORWARD_DECLARE,
"A single type could not identified for the goog.forwardDeclare statement"));
}
if (typeDeclaration != null) {
compiler.forwardDeclareType(typeDeclaration);
}
}
/**
* Verifies that setCssNameMapping is called with the correct methods.
*
* @return Whether the arguments checked out okay
*/
private boolean verifySetCssNameMapping(Node methodName, Node firstArg) {
DiagnosticType diagnostic = null;
if (firstArg == null) {
diagnostic = NULL_ARGUMENT_ERROR;
} else if (!firstArg.isObjectLit()) {
diagnostic = EXPECTED_OBJECTLIT_ERROR;
} else if (firstArg.getNext() != null) {
Node secondArg = firstArg.getNext();
if (!secondArg.isStringLit()) {
diagnostic = EXPECTED_STRING_ERROR;
} else if (secondArg.getNext() != null) {
diagnostic = TOO_MANY_ARGUMENTS_ERROR;
}
}
if (diagnostic != null) {
compiler.report(JSError.make(methodName, diagnostic, methodName.getQualifiedName()));
return false;
}
return true;
}
private void checkPropertyRenameCall(Node call) {
Node callee = call.getFirstChild();
// TODO(b/193038601): make this work when the callee is a module import
if (!compiler.getCodingConvention().isPropertyRenameFunction(callee)) {
return;
}
String calleeName = callee.getQualifiedName();
switch (call.getChildCount() - 1) {
case 1:
case 2:
break;
default:
compiler.report(
JSError.make(
call,
INVALID_RENAME_FUNCTION,
calleeName,
"Must be called with 1 or 2 arguments."));
}
Node propName = callee.getNext();
if (propName == null || !propName.isStringLit()) {
compiler.report(
JSError.make(
call,
INVALID_RENAME_FUNCTION,
calleeName,
"The first argument must be a string literal."));
} else if (propName.getString().contains(".")) {
compiler.report(
JSError.make(
call,
INVALID_RENAME_FUNCTION,
calleeName,
"The first argument must not be a property path."));
}
}
}