Bug 870622 - Unexpected Unix error when filename is not defined. Typechecking for |writeAtomic| function. r=yoric

toolkit/components/osfile/osfile_shared_front.jsm

@@ -342,6 +342,10 @@ AbstractFile.read = function read(path, bytes) {
 AbstractFile.writeAtomic =
      function writeAtomic(path, buffer, options = noOptions) {
 
+  // Verify that path is defined and of the correct type
+  if (typeof path != "string" || path == "") {
+    throw new TypeError("File path should be a (non-empty) string");
+  }
   let noOverwrite = options.noOverwrite;
   if (noOverwrite && OS.File.exists(path)) {
     throw OS.File.Error.exists("writeAtomic");

toolkit/components/osfile/tests/mochi/main_test_osfile_async.js

@@ -479,6 +479,27 @@ let test_read_write_all = maketest("read_write_all", function read_write_all(tes
     // Cleanup.
     OS.File.remove(pathDest);
 
+    // Check that writeAtomic fails when destination path is undefined
+    try {
+      let path = undefined;
+      let options = {tmpPath: tmpPath};
+      yield OS.File.writeAtomic(path, contents, options);
+      test.fail("With file path undefined, writeAtomic should have failed");
+    } catch (err) {
+      test.ok(err.message == "TypeError: File path should be a (non-empty) string",
+              "With file path undefined, writeAtomic correctly failed");
+    }
+
+    // Check that writeAtomic fails when destination path is an empty string
+    try {
+      let path = "";
+      let options = {tmpPath: tmpPath};
+      yield OS.File.writeAtomic(path, contents, options);
+      test.fail("With file path an empty string, writeAtomic should have failed");
+    } catch (err) {
+      test.ok(err.message == "TypeError: File path should be a (non-empty) string",
+              "With file path an empty string, writeAtomic correctly failed");
+    }
   });
 });
 

toolkit/components/osfile/tests/mochi/worker_test_osfile_front.js

@@ -338,6 +338,28 @@ function test_readall_writeall_file()
   }
   ok(!!exn && exn instanceof TypeError, "writeAtomic fails if tmpPath is not provided");
 
+  // Check that writeAtomic fails when destination path is undefined
+  exn = null;
+  try {
+    let path = undefined;
+    let options = {tmpPath: tmp_file_name};
+    OS.File.writeAtomic(path, readResult.buffer, options);
+  } catch (x) {
+    exn = x;
+  }
+  ok(!!exn && exn instanceof TypeError, "writeAtomic fails if path is undefined");
+
+  // Check that writeAtomic fails when destination path is an empty string
+  exn = null;
+  try {
+    let path = "";
+    let options = {tmpPath: tmp_file_name};
+    OS.File.writeAtomic(path, readResult.buffer, options);
+  } catch (x) {
+    exn = x;
+  }
+  ok(!!exn && exn instanceof TypeError, "writeAtomic fails if path is an empty string");
+
   // Cleanup.
   OS.File.remove(tmp_file_name);
 }