[vm/ffi] Add copyright headers to sqlite example and incorporate Michael's feedback.

Change-Id: I83555a81bb6394a8c2a740a5127175be85aabf3d
Reviewed-on: https://dart-review.googlesource.com/c/sdk/+/98007
Commit-Queue: Samir Jindel <sjindel@google.com>
Reviewed-by: Michael Thomsen <mit@google.com>
Auto-Submit: Samir Jindel <sjindel@google.com>

samples/ffi/sqlite/README.md

@@ -6,7 +6,7 @@ This is an illustrative sample for how to use `dart:ffi`.
 ## Building and Running this Sample
 
 Building and running this sample is done through pub.
-Running `pub get` and `pub run test` should produce the following output.
+Running `pub get` and `pub run example/main` should produce the following output.
 
 ```sh
 $ pub get
@@ -24,8 +24,7 @@ Precompiled test:test.
 ```
 
 ```
-$ pub run test
-00:01 +0: test/sqlite_test.dart: sqlite integration test
+$ pub run example/main
 1 Chocolade chip cookie Chocolade cookie foo
 2 Ginger cookie null 42
 3 Cinnamon roll null null
@@ -33,7 +32,6 @@ $ pub run test
 2 Ginger cookie null 42
 expected exception on accessing result data after close: The result has already been closed.
 expected this query to fail: no such column: non_existing_column (Code 1: SQL logic error)
-00:02 +3: All tests passed!
 ```
 
 ## Tutorial

samples/ffi/sqlite/example/main.dart

@@ -0,0 +1,84 @@
+// Copyright (c) 2019, the Dart project authors.  Please see the AUTHORS file
+// for details. All rights reserved. Use of this source code is governed by a
+// BSD-style license that can be found in the LICENSE file.
+
+import "package:test/test.dart";
+
+import "../lib/sqlite.dart";
+
+void main() {
+  Database d = Database("test.db");
+  d.execute("drop table if exists Cookies;");
+  d.execute("""
+      create table Cookies (
+        id integer primary key,
+        name text not null,
+        alternative_name text
+      );""");
+  d.execute("""
+      insert into Cookies (id, name, alternative_name)
+      values
+        (1,'Chocolade chip cookie', 'Chocolade cookie'),
+        (2,'Ginger cookie', null),
+        (3,'Cinnamon roll', null)
+      ;""");
+  Result result = d.query("""
+      select
+        id,
+        name,
+        alternative_name,
+        case
+          when id=1 then 'foo'
+          when id=2 then 42
+          when id=3 then null
+        end as multi_typed_column
+      from Cookies
+      ;""");
+  for (Row r in result) {
+    int id = r.readColumnAsInt("id");
+    String name = r.readColumnByIndex(1);
+    String alternativeName = r.readColumn("alternative_name");
+    dynamic multiTypedValue = r.readColumn("multi_typed_column");
+    print("$id $name $alternativeName $multiTypedValue");
+  }
+  result = d.query("""
+      select
+        id,
+        name,
+        alternative_name,
+        case
+          when id=1 then 'foo'
+          when id=2 then 42
+          when id=3 then null
+        end as multi_typed_column
+      from Cookies
+      ;""");
+  for (Row r in result) {
+    int id = r.readColumnAsInt("id");
+    String name = r.readColumnByIndex(1);
+    String alternativeName = r.readColumn("alternative_name");
+    dynamic multiTypedValue = r.readColumn("multi_typed_column");
+    print("$id $name $alternativeName $multiTypedValue");
+    if (id == 2) {
+      result.close();
+      break;
+    }
+  }
+  try {
+    result.iterator.moveNext();
+  } on SQLiteException catch (e) {
+    print("expected exception on accessing result data after close: $e");
+  }
+  try {
+    d.query("""
+      select
+        id,
+        non_existing_column
+      from Cookies
+      ;""");
+  } on SQLiteException catch (e) {
+    print("expected this query to fail: $e");
+  }
+  d.execute("drop table Cookies;");
+  d.close();
+}

samples/ffi/sqlite/lib/sqlite.dart

@@ -1,3 +1,7 @@
+// Copyright (c) 2019, the Dart project authors.  Please see the AUTHORS file
+// for details. All rights reserved. Use of this source code is governed by a
+// BSD-style license that can be found in the LICENSE file.
+
 /// A synchronous SQLite wrapper.
 ///
 /// Written using dart:ffi.

samples/ffi/sqlite/lib/src/bindings/bindings.dart

@@ -1,3 +1,7 @@
+// Copyright (c) 2019, the Dart project authors.  Please see the AUTHORS file
+// for details. All rights reserved. Use of this source code is governed by a
+// BSD-style license that can be found in the LICENSE file.
+
 import "dart:ffi";
 
 import "../ffi/cstring.dart";

samples/ffi/sqlite/lib/src/bindings/constants.dart

@@ -1,3 +1,7 @@
+// Copyright (c) 2019, the Dart project authors.  Please see the AUTHORS file
+// for details. All rights reserved. Use of this source code is governed by a
+// BSD-style license that can be found in the LICENSE file.
+
 /// Result Codes
 ///
 /// Many SQLite functions return an integer result code from the set shown

samples/ffi/sqlite/lib/src/bindings/signatures.dart

@@ -1,3 +1,7 @@
+// Copyright (c) 2019, the Dart project authors.  Please see the AUTHORS file
+// for details. All rights reserved. Use of this source code is governed by a
+// BSD-style license that can be found in the LICENSE file.
+
 import "dart:ffi";
 
 import "../ffi/cstring.dart";

samples/ffi/sqlite/lib/src/bindings/types.dart

@@ -1,3 +1,7 @@
+// Copyright (c) 2019, the Dart project authors.  Please see the AUTHORS file
+// for details. All rights reserved. Use of this source code is governed by a
+// BSD-style license that can be found in the LICENSE file.
+
 import "dart:ffi";
 
 import "../ffi/cstring.dart";

samples/ffi/sqlite/lib/src/collections/closable_iterator.dart

@@ -1,3 +1,7 @@
+// Copyright (c) 2019, the Dart project authors.  Please see the AUTHORS file
+// for details. All rights reserved. Use of this source code is governed by a
+// BSD-style license that can be found in the LICENSE file.
+
 /// This iterator should be [close]d after use.
 ///
 /// [ClosableIterator]s often use resources which should be freed after use.

samples/ffi/sqlite/lib/src/database.dart

@@ -1,3 +1,7 @@
+// Copyright (c) 2019, the Dart project authors.  Please see the AUTHORS file
+// for details. All rights reserved. Use of this source code is governed by a
+// BSD-style license that can be found in the LICENSE file.
+
 import "dart:collection";
 import "dart:ffi";
 

samples/ffi/sqlite/lib/src/ffi/arena.dart

@@ -1,3 +1,7 @@
+// Copyright (c) 2019, the Dart project authors.  Please see the AUTHORS file
+// for details. All rights reserved. Use of this source code is governed by a
+// BSD-style license that can be found in the LICENSE file.
+
 import "dart:async";
 import "dart:ffi";
 

samples/ffi/sqlite/lib/src/ffi/cstring.dart

@@ -1,3 +1,7 @@
+// Copyright (c) 2019, the Dart project authors.  Please see the AUTHORS file
+// for details. All rights reserved. Use of this source code is governed by a
+// BSD-style license that can be found in the LICENSE file.
+
 import "dart:convert";
 import "dart:ffi";
 

samples/ffi/sqlite/test/sqlite_test.dart

@@ -1,3 +1,7 @@
+// Copyright (c) 2019, the Dart project authors.  Please see the AUTHORS file
+// for details. All rights reserved. Use of this source code is governed by a
+// BSD-style license that can be found in the LICENSE file.
+
 // VMOptions=--optimization-counter-threshold=5
 
 import "package:test/test.dart";