Fix #172 by desugaring Import filenames.

core/desugarer.cpp

@@ -643,11 +643,17 @@ class Desugarer {
             desugar(ast->body, obj_level);
             desugarParams(ast->params, obj_level);
 
-        } else if (dynamic_cast<const Import *>(ast_)) {
-            // Nothing to do.
-
-        } else if (dynamic_cast<const Importstr *>(ast_)) {
-            // Nothing to do.
+        } else if (auto *ast = dynamic_cast<Import *>(ast_)) {
+            // TODO(dcunnin): Abstract this into a template function if it becomes more common.
+            AST *file = ast->file;
+            desugar(file, obj_level);
+            ast->file = dynamic_cast<LiteralString*>(file);
+
+        } else if (auto *ast = dynamic_cast<Importstr *>(ast_)) {
+            // TODO(dcunnin): Abstract this into a template function if it becomes more common.
+            AST *file = ast->file;
+            desugar(file, obj_level);
+            ast->file = dynamic_cast<LiteralString*>(file);
 
         } else if (auto *ast = dynamic_cast<InSuper *>(ast_)) {
             desugar(ast->element, obj_level);

core/string_utils.h

@@ -22,6 +22,11 @@ limitations under the License.
 /** Unparse the string. */
 UString jsonnet_string_unparse(const UString &str, bool single);
 
+
+// Note that the following two functions do not handle the quoting of ' and "
+// inside verbatim strings because that quoting is reversible.  Thus, that
+// quoting is done at lexing time and undone again at pretty-printing time.
+
 /** Escape special characters. */
 UString jsonnet_string_escape(const UString &str, bool single);
 

doc/language/spec.html

@@ -138,7 +138,8 @@ <h2 id="lexing">Lexing</h2>
 first subsequent line that does not begin with <i>W</i>, and it is an error if this line does not
 contain some optional whitespace followed by <code>|||</code>.  The content of the string is the
 concatenation of all the lines that began with <i>W</i> but with that prefix stripped.  The line
-ending style in the file is preserved in the string.</li>
+ending style in the file is preserved in the string.  This form cannot be used in
+<code>import</code> statements.</li>
 </ul>
 
 <p>Double- and single-quoted strings are allowed to span multiple lines, in which case whatever

test_suite/error.parse.import_text_block.jsonnet

@@ -0,0 +1,20 @@
+/*
+Copyright 2017 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.
+*/
+
+import |||
+  This is a paragraph of text, which is being used in the place of
+  a filename.  That is quite unusual, and probably not intended.
+|||

test_suite/error.parse.import_text_block.jsonnet.golden

@@ -0,0 +1 @@
+STATIC ERROR: error.parse.import_text_block.jsonnet:(17:8)-(20:3): Cannot use text blocks in import statements.

test_suite/import.jsonnet

@@ -17,14 +17,20 @@ limitations under the License.
 // Can capture variables from another file.
 std.assertEqual((import "lib/A_20_func.libsonnet")(), 20) &&
 
+// Ensure string is quoted.
+std.assertEqual((import "lib/\u0041_20_func.libsonnet")(), 20) &&
+
 # Test single quoted string.
 std.assertEqual((import 'lib/A_20_func.libsonnet')(), 20) &&
 # The block string is hard to test because the filename would include a terminating \n
 
 // Each import has its own environment, can't be overidden.
 std.assertEqual(local A = 7; local lib = import "lib/A_20.libsonnet"; lib, 20) &&
 std.assertEqual(local A = 7, lib = import "lib/A_20.libsonnet"; lib, 20) &&
+
 std.assertEqual(importstr "lib/some_file.txt", "Hello World!\n") &&
+std.assertEqual(importstr "lib/\u0073ome_file.txt", "Hello World!\n") &&
+
 std.assertEqual(import "lib/rel_path.libsonnet", "rel_path") &&
 std.assertEqual(import "lib/rel_path4.libsonnet", "rel_path") &&