Add initial prototype for the GN meta-buildsystem.

tools/gn/parser_unittest.cc

Index: tools/gn/parser_unittest.cc
diff --git a/tools/gn/parser_unittest.cc b/tools/gn/parser_unittest.cc
new file mode 100644
index 0000000000000000000000000000000000000000..3fd8ebe28db8c70776fa671ae6d02749a53d6448
--- /dev/null
+++ b/tools/gn/parser_unittest.cc
@@ -0,0 +1,329 @@
+// Copyright (c) 2013 The Chromium Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style license that can be
+// found in the LICENSE file.
+
+#include <iostream>
+#include <sstream>
+
+#include "testing/gtest/include/gtest/gtest.h"
+#include "tools/gn/input_file.h"
+#include "tools/gn/parser.h"
+#include "tools/gn/tokenizer.h"
+
+namespace {
+
+bool GetTokens(const InputFile* input, std::vector<Token>* result) {
+  result->clear();
+  Err err;
+  *result = Tokenizer::Tokenize(input, &err);
+  return !err.has_error();
+}
+
+bool IsIdentifierEqual(const ParseNode* node, const char* val) {
+  if (!node)
+    return false;
+  const IdentifierNode* ident = node->AsIdentifier();
+  if (!ident)
+    return false;
+  return ident->value().value() == val;
+}
+
+bool IsLiteralEqual(const ParseNode* node, const char* val) {
+  if (!node)
+    return false;
+  const LiteralNode* lit = node->AsLiteral();
+  if (!lit)
+    return false;
+  return lit->value().value() == val;
+}
+
+// Returns true if the given node as a simple assignment to a given value.
+bool IsAssignment(const ParseNode* node, const char* ident, const char* value) {
+  if (!node)
+    return false;
+  const BinaryOpNode* binary = node->AsBinaryOp();
+  if (!binary)
+    return false;
+  return binary->op().IsOperatorEqualTo("=") &&
+         IsIdentifierEqual(binary->left(), ident) &&
+         IsLiteralEqual(binary->right(), value);
+}
+
+// Returns true if the given node is a block with one assignment statement.
+bool IsBlockWithAssignment(const ParseNode* node,
+                           const char* ident, const char* value) {
+  if (!node)
+    return false;
+  const BlockNode* block = node->AsBlock();
+  if (!block)
+    return false;
+  if (block->statements().size() != 1)
+    return false;
+  return IsAssignment(block->statements()[0], ident, value);
+}
+
+void DoParserPrintTest(const char* input, const char* expected) {
+  std::vector<Token> tokens;
+  InputFile input_file(SourceFile("/test"));
+  input_file.SetContents(input);
+  ASSERT_TRUE(GetTokens(&input_file, &tokens));
+
+  Err err;
+  scoped_ptr<ParseNode> result = Parser::Parse(tokens, &err);
+  ASSERT_TRUE(result);
+
+  std::ostringstream collector;
+  result->Print(collector, 0);
+
+  EXPECT_EQ(expected, collector.str());
+}
+
+// Expects the tokenizer or parser to identify an error at the given line and
+// character.
+void DoParserErrorTest(const char* input, int err_line, int err_char) {
+  InputFile input_file(SourceFile("/test"));
+  input_file.SetContents(input);
+
+  Err err;
+  std::vector<Token> tokens = Tokenizer::Tokenize(&input_file, &err);
+  if (!err.has_error()) {
+    scoped_ptr<ParseNode> result = Parser::Parse(tokens, &err);
+    ASSERT_FALSE(result);
+    ASSERT_TRUE(err.has_error());
+  }
+
+  EXPECT_EQ(err_line, err.location().line_number());
+  EXPECT_EQ(err_char, err.location().char_offset());
+}
+
+}  // namespace
+
+TEST(Parser, BinaryOp) {
+  std::vector<Token> tokens;
+
+  // Simple set expression.
+  InputFile expr_input(SourceFile("/test"));
+  expr_input.SetContents("a=2");
+  ASSERT_TRUE(GetTokens(&expr_input, &tokens));
+  Err err;
+  Parser set(tokens, &err);
+  scoped_ptr<ParseNode> expr = set.ParseExpression();
+  ASSERT_TRUE(expr);
+
+  const BinaryOpNode* binary_op = expr->AsBinaryOp();
+  ASSERT_TRUE(binary_op);
+
+  EXPECT_TRUE(binary_op->left()->AsIdentifier());
+
+  EXPECT_TRUE(binary_op->op().type() == Token::OPERATOR);
+  EXPECT_TRUE(binary_op->op().value() == "=");
+
+  EXPECT_TRUE(binary_op->right()->AsLiteral());
+}
+
+TEST(Parser, Condition) {
+  std::vector<Token> tokens;
+
+  InputFile cond_input(SourceFile("/test"));
+  cond_input.SetContents("if(1) { a = 2 }");
+  ASSERT_TRUE(GetTokens(&cond_input, &tokens));
+  Err err;
+  Parser simple_if(tokens, &err);
+  scoped_ptr<ConditionNode> cond = simple_if.ParseCondition();
+  ASSERT_TRUE(cond);
+
+  EXPECT_TRUE(IsLiteralEqual(cond->condition(), "1"));
+  EXPECT_FALSE(cond->if_false());  // No else block.
+  EXPECT_TRUE(IsBlockWithAssignment(cond->if_true(), "a", "2"));
+
+  // Now try a complicated if/else if/else one.
+  InputFile complex_if_input(SourceFile("/test"));
+  complex_if_input.SetContents(
+      "if(1) { a = 2 } else if (0) { a = 3 } else { a = 4 }");
+  ASSERT_TRUE(GetTokens(&complex_if_input, &tokens));
+  Parser complex_if(tokens, &err);
+  cond = complex_if.ParseCondition();
+  ASSERT_TRUE(cond);
+
+  EXPECT_TRUE(IsLiteralEqual(cond->condition(), "1"));
+  EXPECT_TRUE(IsBlockWithAssignment(cond->if_true(), "a", "2"));
+
+  ASSERT_TRUE(cond->if_false());
+  const ConditionNode* nested_cond = cond->if_false()->AsConditionNode();
+  ASSERT_TRUE(nested_cond);
+  EXPECT_TRUE(IsLiteralEqual(nested_cond->condition(), "0"));
+  EXPECT_TRUE(IsBlockWithAssignment(nested_cond->if_true(), "a", "3"));
+  EXPECT_TRUE(IsBlockWithAssignment(nested_cond->if_false(), "a", "4"));
+}
+
+TEST(Parser, FunctionCall) {
+  const char* input = "foo(a, 1, 2,) bar()";
+  const char* expected =
+      "BLOCK\n"
+      " FUNCTION(foo)\n"
+      "  LIST\n"
+      "   IDENTIFIER(a)\n"
+      "   LITERAL(1)\n"
+      "   LITERAL(2)\n"
+      " FUNCTION(bar)\n"
+      "  LIST\n";
+  DoParserPrintTest(input, expected);
+}
+
+TEST(Parser, ParenExpression) {
+  const char* input = "(foo(1)) + (a + b)";
+  const char* expected =
+      "BLOCK\n"
+      " BINARY(+)\n"
+      "  FUNCTION(foo)\n"
+      "   LIST\n"
+      "    LITERAL(1)\n"
+      "  BINARY(+)\n"
+      "   IDENTIFIER(a)\n"
+      "   IDENTIFIER(b)\n";
+  DoParserPrintTest(input, expected);
+  DoParserErrorTest("(a +", 1, 4);
+}
+
+TEST(Parser, UnaryOp) {
+  std::vector<Token> tokens;
+
+  InputFile ident_input(SourceFile("/test"));
+  ident_input.SetContents("!foo");
+  ASSERT_TRUE(GetTokens(&ident_input, &tokens));
+  Err err;
+  Parser ident(tokens, &err);
+  scoped_ptr<UnaryOpNode> op = ident.ParseUnaryOp();
+
+  ASSERT_TRUE(op);
+  EXPECT_TRUE(op->op().type() == Token::OPERATOR);
+  EXPECT_TRUE(op->op().value() == "!");
+}
+
+TEST(Parser, CompleteFunction) {
+  const char* input =
+      "cc_test(\"foo\") {\n"
+      "  sources = [\n"
+      "    \"foo.cc\",\n"
+      "    \"foo.h\"\n"
+      "  ]\n"
+      "  dependencies = [\n"
+      "    \"base\"\n"
+      "  ]\n"
+      "}\n";
+  const char* expected =
+      "BLOCK\n"
+      " FUNCTION(cc_test)\n"
+      "  LIST\n"
+      "   LITERAL(\"foo\")\n"
+      "  BLOCK\n"
+      "   BINARY(=)\n"
+      "    IDENTIFIER(sources)\n"
+      "    LIST\n"
+      "     LITERAL(\"foo.cc\")\n"
+      "     LITERAL(\"foo.h\")\n"
+      "   BINARY(=)\n"
+      "    IDENTIFIER(dependencies)\n"
+      "    LIST\n"
+      "     LITERAL(\"base\")\n";
+  DoParserPrintTest(input, expected);
+}
+
+TEST(Parser, FunctionWithConditional) {
+  const char* input =
+      "cc_test(\"foo\") {\n"
+      "  sources = [\"foo.cc\"]\n"
+      "  if (OS == \"mac\") {\n"
+      "    sources += \"bar.cc\"\n"
+      "  } else if (OS == \"win\") {\n"
+      "    sources -= [\"asd.cc\", \"foo.cc\"]\n"
+      "  } else {\n"
+      "    dependencies += [\"bar.cc\"]\n"
+      "  }\n"
+      "}\n";
+  const char* expected =
+      "BLOCK\n"
+      " FUNCTION(cc_test)\n"
+      "  LIST\n"
+      "   LITERAL(\"foo\")\n"
+      "  BLOCK\n"
+      "   BINARY(=)\n"
+      "    IDENTIFIER(sources)\n"
+      "    LIST\n"
+      "     LITERAL(\"foo.cc\")\n"
+      "   CONDITION\n"
+      "    BINARY(==)\n"
+      "     IDENTIFIER(OS)\n"
+      "     LITERAL(\"mac\")\n"
+      "    BLOCK\n"
+      "     BINARY(+=)\n"
+      "      IDENTIFIER(sources)\n"
+      "      LITERAL(\"bar.cc\")\n"
+      "    CONDITION\n"
+      "     BINARY(==)\n"
+      "      IDENTIFIER(OS)\n"
+      "      LITERAL(\"win\")\n"
+      "     BLOCK\n"
+      "      BINARY(-=)\n"
+      "       IDENTIFIER(sources)\n"
+      "       LIST\n"
+      "        LITERAL(\"asd.cc\")\n"
+      "        LITERAL(\"foo.cc\")\n"
+      "     BLOCK\n"
+      "      BINARY(+=)\n"
+      "       IDENTIFIER(dependencies)\n"
+      "       LIST\n"
+      "        LITERAL(\"bar.cc\")\n";
+  DoParserPrintTest(input, expected);
+}
+
+TEST(Parser, NestedBlocks) {
+  const char* input = "{cc_test(\"foo\") {{foo=1}{}}}";
+  const char* expected =
+      "BLOCK\n"
+      " BLOCK\n"
+      "  FUNCTION(cc_test)\n"
+      "   LIST\n"
+      "    LITERAL(\"foo\")\n"
+      "   BLOCK\n"
+      "    BLOCK\n"
+      "     BINARY(=)\n"
+      "      IDENTIFIER(foo)\n"
+      "      LITERAL(1)\n"
+      "    BLOCK\n";
+  DoParserPrintTest(input, expected);
+}
+
+TEST(Parser, List) {
+  const char* input = "[] a = [1,asd,] b = [1, 2+3 - foo]";
+  const char* expected =
+      "BLOCK\n"
+      " LIST\n"
+      " BINARY(=)\n"
+      "  IDENTIFIER(a)\n"
+      "  LIST\n"
+      "   LITERAL(1)\n"
+      "   IDENTIFIER(asd)\n"
+      " BINARY(=)\n"
+      "  IDENTIFIER(b)\n"
+      "  LIST\n"
+      "   LITERAL(1)\n"
+      "   BINARY(+)\n"
+      "    LITERAL(2)\n"
+      "    BINARY(-)\n"
+      "     LITERAL(3)\n"
+      "     IDENTIFIER(foo)\n";
+  DoParserPrintTest(input, expected);
+
+  DoParserErrorTest("[a, 2+,]", 1, 7);
+  DoParserErrorTest("[,]", 1, 2);
+  DoParserErrorTest("[a,,]", 1, 4);
+}
+
+TEST(Parser, UnterminatedBlock) {
+  DoParserErrorTest("hello {", 1, 7);
+}
+
+TEST(Parser, BadlyTerminatedNumber) {
+  DoParserErrorTest("1234z", 1, 5);
+}