add scripts to run/debug DDC output on simple test cases

pkg/dev_compiler/tool/ddc

Index: pkg/dev_compiler/tool/ddc
diff --git a/pkg/dev_compiler/tool/ddc b/pkg/dev_compiler/tool/ddc
new file mode 100755
index 0000000000000000000000000000000000000000..0fa6f37645699ee6987da21adcf69d8420bfe6cf
--- /dev/null
+++ b/pkg/dev_compiler/tool/ddc
@@ -0,0 +1,27 @@
+#!/bin/bash
+#
+# Compiles code with DDC and runs the resulting code in node.js.
+#
+# The first script supplied should be the one with `main()`.
+#
+# Saves the output in the same directory as the sources for convenient
+# inspection, modification or rerunning the code.
+#
+set -e
+DDC_PATH=$( cd $( dirname "${BASH_SOURCE[0]}" )/.. && pwd )
+BASENAME=$( basename "${1%.*}")
+LIBROOT=$(cd $( dirname "${1%.*}") && pwd)
+export NODE_PATH=$DDC_PATH/lib/js/common:$LIBROOT:$NODE_PATH
+dart -c $DDC_PATH/bin/dartdevc.dart --modules=node --library-root=$LIBROOT \
+    --dart-sdk-summary=$DDC_PATH/lib/sdk/ddc_sdk.sum \
+    -o $LIBROOT/$BASENAME.js $*
+pushd $LIBROOT > /dev/null
+# TODO(jmesserly): we could have this output the same content as the devtool
+# script, so you could debug the output without recompiling?
+echo "
+    let sdk = require(\"dart_sdk\");
+    let main = require(\"$BASENAME\").$BASENAME.main;
+    sdk._isolate_helper.startRootIsolate(main, []);" \
+    > $LIBROOT/$BASENAME.run.js
+node $BASENAME.run.js
+popd > /dev/null