SetFullCalleeNamesVisitor.java

/*
 * Copyright 2008 Google Inc.
 *
 * 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.template.soy.passes;

import com.google.common.base.Preconditions;
import com.google.template.soy.error.ErrorReporter;
import com.google.template.soy.error.SoyErrorKind;
import com.google.template.soy.soytree.AbstractSoyNodeVisitor;
import com.google.template.soy.soytree.CallBasicNode;
import com.google.template.soy.soytree.SoyFileNode;
import com.google.template.soy.soytree.SoyFileSetNode;
import com.google.template.soy.soytree.SoyNode;
import com.google.template.soy.soytree.SoyNode.ParentSoyNode;
import java.util.Map;

/**
 * Sets the full callee name on each {@link CallBasicNode} whose callee name in the source code
 * either is a partial template name or starts with an alias.
 *
 * <p>{@link #exec} should be called on a full parse tree or a Soy file. This pass mutates
 * CallBasicNodes. There is no return value.
 *
 * <p>TODO(brndn): consider folding into TemplateParser.
 *
 */
final class SetFullCalleeNamesVisitor extends AbstractSoyNodeVisitor<Void> {

  private static final SoyErrorKind CALL_COLLIDES_WITH_NAMESPACE_ALIAS =
      SoyErrorKind.of("Call collides with namespace alias ''{0}''");

  /** The namespace of the current file that we're in (during the pass). */
  private String currNamespace;

  /** Alias-to-namespace map of the current file (during the pass). */
  private Map<String, String> currAliasToNamespaceMap;

  private final ErrorReporter errorReporter;

  SetFullCalleeNamesVisitor(ErrorReporter errorReporter) {
    this.errorReporter = errorReporter;
  }

  @Override
  public Void exec(SoyNode soyNode) {
    Preconditions.checkArgument(
        soyNode instanceof SoyFileSetNode || soyNode instanceof SoyFileNode);
    return super.exec(soyNode);
  }

  // -----------------------------------------------------------------------------------------------
  // Implementations for specific nodes.

  @Override
  protected void visitSoyFileNode(SoyFileNode node) {
    currNamespace = node.getNamespace();
    currAliasToNamespaceMap = node.getAliasToNamespaceMap();
    visitChildren(node);
  }

  @Override
  protected void visitCallBasicNode(CallBasicNode node) {

    String srcCalleeName = node.getSrcCalleeName();
    // TODO: If feasible, change existing instances and remove the startsWith(".") part below.
    if (srcCalleeName.startsWith(".")) {
      // Case 1: Source callee name is partial.
      node.setCalleeName(currNamespace + srcCalleeName);
    } else if (srcCalleeName.contains(".")) {
      // Case 2: Source callee name is a proper dotted ident.
      String[] parts = srcCalleeName.split("[.]", 2);
      if (currAliasToNamespaceMap.containsKey(parts[0])) {
        // Case 2a: Source callee name's first part is an alias.
        String aliasNamespace = currAliasToNamespaceMap.get(parts[0]);
        node.setCalleeName(aliasNamespace + '.' + parts[1]);
      } else {
        // Case 2b: Source callee name's first part is not an alias.
        node.setCalleeName(srcCalleeName);
      }
    } else {
      // Case 3: Source callee name is a single ident (not dotted).
      if (currAliasToNamespaceMap.containsKey(srcCalleeName)) {
        errorReporter.report(
            node.getSourceLocation(), CALL_COLLIDES_WITH_NAMESPACE_ALIAS, srcCalleeName);
      }
      node.setCalleeName(srcCalleeName);
    }

    visitChildren(node);
  }

  // -----------------------------------------------------------------------------------------------
  // Fallback implementation.

  @Override
  protected void visitSoyNode(SoyNode node) {
    if (node instanceof ParentSoyNode<?>) {
      visitChildren((ParentSoyNode<?>) node);
    }
  }
}