1 files changed, 97 insertions, 0 deletions
diff --git a/src/main/java/com/google/devtools/build/lib/syntax/FunctionDefStatement.java b/src/main/java/com/google/devtools/build/lib/syntax/FunctionDefStatement.java
new file mode 100644
index 0000000000..29ed579e47
--- /dev/null
+++ b/src/main/java/com/google/devtools/build/lib/syntax/FunctionDefStatement.java
@@ -0,0 +1,97 @@
+// Copyright 2014 Google Inc. All rights reserved.
+//
+// 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.devtools.build.lib.syntax;
+
+import com.google.common.base.Preconditions;
+import com.google.common.collect.ImmutableList;
+import com.google.common.collect.ImmutableMap;
+import com.google.devtools.build.lib.syntax.SkylarkType.SkylarkFunctionType;
+
+import java.util.Collection;
+
+/**
+ * Syntax node for a function definition.
+ */
+public class FunctionDefStatement extends Statement {
+
+  private final Ident ident;
+  private final ImmutableList<Argument> args;
+  private final ImmutableList<Statement> statements;
+
+  public FunctionDefStatement(Ident ident, Collection<Argument> args,
+      Collection<Statement> statements) {
+    for (Argument arg : args) {
+      Preconditions.checkArgument(arg.isNamed());
+    }
+    this.ident = ident;
+    this.args = ImmutableList.copyOf(args);
+    this.statements = ImmutableList.copyOf(statements);
+  }
+
+  @Override
+  void exec(Environment env) throws EvalException, InterruptedException {
+    ImmutableMap.Builder<String, Object> defaultValues = ImmutableMap.builder();
+    for (Argument arg : args) {
+      if (arg.hasValue()) {
+        defaultValues.put(arg.getArgName(), arg.getValue().eval(env));
+      }
+    }
+    env.update(ident.getName(), new UserDefinedFunction(
+        ident, args, defaultValues.build(), statements, (SkylarkEnvironment) env));
+  }
+
+  @Override
+  public String toString() {
+    return "def " + ident + "(" + args + "):\n";
+  }
+
+  public Ident getIdent() {
+    return ident;
+  }
+
+  public ImmutableList<Statement> getStatements() {
+    return statements;
+  }
+
+  public ImmutableList<Argument> getArgs() {
+    return args;
+  }
+
+  @Override
+  public void accept(SyntaxTreeVisitor visitor) {
+    visitor.visit(this);
+  }
+
+  @Override
+  void validate(ValidationEnvironment env) throws EvalException {
+    SkylarkFunctionType type = SkylarkFunctionType.of(ident.getName());
+    ValidationEnvironment localEnv = new ValidationEnvironment(env, type);
+    for (Argument i : args) {
+      SkylarkType argType = SkylarkType.UNKNOWN;
+      if (i.hasValue()) {
+        argType = i.getValue().validate(env);
+        if (argType.equals(SkylarkType.NONE)) {
+          argType = SkylarkType.UNKNOWN;
+        }
+      }
+      localEnv.update(i.getArgName(), argType, getLocation());
+    }
+    for (Statement stmts : statements) {
+      stmts.validate(localEnv);
+    }
+    env.updateFunction(ident.getName(), type, getLocation());
+    // Register a dummy return value with an incompatible type if there was no return statement.
+    type.setReturnType(SkylarkType.NONE, getLocation());
+  }
+}