better error if published source has no handler

tools/compiler-plugin.js

@@ -47,6 +47,11 @@ _.extend(exports.CompilerPluginProcessor.prototype, {
       return new PackageSourceBatch(unibuild, self);
     });
 
+    // If we failed to match sources with processors, we're done.
+    if (buildmessage.jobHasMessages()) {
+      return [];
+    }
+
     // Find out which files go with which CompilerPlugins.
     _.each(sourceBatches, function (sourceBatch) {
       _.each(sourceBatch.resourceSlots, function (resourceSlot) {
@@ -384,7 +389,8 @@ var PackageSourceBatch = function (unibuild, processor) {
   self.processor = processor;
   var sourceProcessorsByExtension =
         self._getSourceProcessorsByExtension();
-  self.resourceSlots = _.map(unibuild.resources, function (resource) {
+  self.resourceSlots = [];
+  unibuild.resources.forEach(function (resource) {
     var sourceProcessor = null;
     if (resource.type === "source") {
       var extension = resource.extension;
@@ -394,11 +400,15 @@ var PackageSourceBatch = function (unibuild, processor) {
       } else if (_.has(sourceProcessorsByExtension, extension)) {
         sourceProcessor = sourceProcessorsByExtension[extension];
       } else {
-        // XXX BBP better error handling
-        throw Error("no plugin found for " + JSON.stringify(resource));
+        buildmessage.error(
+          `no plugin found for ${ resource.path } in ` +
+          `${ unibuild.pkg.displayName() }; a plugin for *.${ extension } ` +
+          `was active when it was published but none is now`);
+        return;
+        // recover by ignoring
       }
     }
-    return new ResourceSlot(resource, sourceProcessor, self);
+    self.resourceSlots.push(new ResourceSlot(resource, sourceProcessor, self));
   });
 };
 _.extend(PackageSourceBatch.prototype, {

tools/tests/apps/uses-published-package-with-inactive-source/.meteor/.gitignore

@@ -0,0 +1 @@
+local

tools/tests/apps/uses-published-package-with-inactive-source/.meteor/.id

@@ -0,0 +1,7 @@
+# This file contains a token that is unique to your project.
+# Check it into your repository along with the rest of this directory.
+# It can be used for purposes such as:
+#   - ensuring you don't accidentally deploy one app on top of another
+#   - providing package authors with aggregated statistics
+
+140b34e2hn59de0acc2

tools/tests/apps/uses-published-package-with-inactive-source/.meteor/packages

@@ -0,0 +1,8 @@
+# Meteor packages used by this project, one per line.
+#
+# 'meteor add' and 'meteor remove' will edit this file for you,
+# but you can also edit it by hand.
+
+meteor-platform
+local-plugin
+glasser:use-sourcish@=0.0.1

tools/tests/apps/uses-published-package-with-inactive-source/.meteor/release

@@ -0,0 +1 @@
+none

tools/tests/apps/uses-published-package-with-inactive-source/packages/local-plugin/package.js

@@ -0,0 +1,3 @@
+Package.describe({
+  version: '1.0.0'
+});

tools/tests/batch-plugins.js

@@ -216,3 +216,27 @@ selftest.define("compiler plugins - duplicate extension", () => {
 
   run.stop();
 });
+
+// Test error when a source file no longer has an active plugin.
+selftest.define("compiler plugins - inactive source", () => {
+  const s = new Sandbox({ fakeMongo: true });
+
+  // This app depends on the published package 'glasser:uses-sourcish', and
+  // contains a local package 'local-plugin'.
+  //
+  // glasser:uses-sourcish depends on local-plugin and contains a file
+  // 'foo.sourcish'. When glasser:uses-sourcish@0.0.1 was published, a local
+  // copy of 'local-plugin' had a plugin which called registerCompiler for the
+  // extension '*.sourcish', and so 'foo.sourcish' is in the published isopack
+  // as a source file. However, the copy of 'local-plugin' currently in the test
+  // app contains no plugins. So we hit this weird error.
+  s.createApp('myapp', 'uses-published-package-with-inactive-source');
+  s.cd('myapp');
+
+  let run = startRun(s);
+  run.match('Errors prevented startup');
+  run.match('no plugin found for foo.sourcish in glasser:use-sourcish');
+  run.match('none is now');
+
+  run.stop();
+});