Fix another regression in rake task pattern handling.

This was reported by @aprescott: #1671 (comment).

The regression was originally introduced in #1653.
See also #1691 and #1692.

Changelog.md

@@ -1,3 +1,13 @@
+### 3.1.1 Development
+[Full Changelog](http://github.com/rspec/rspec-core/compare/v3.1.0...3-1-maintenance)
+
+Bug Fixes:
+
+* Fix a regression in rake task pattern handling, so that `rake_task.pattern = array`
+  works again. While we never intended to support array values (or even knew that worked!),
+  the implementation from 3.0 and earlier used `FileList` internally, which allows arrays.
+  The fix restores the old behavior. (Myron Marston, #1694)
+
 ### 3.1.0 / 2014-09-04
 [Full Changelog](http://github.com/rspec/rspec-core/compare/v3.0.4...v3.1.0)
 

lib/rspec/core/rake_task.rb

@@ -114,15 +114,25 @@ def define(args, &task_block)
       def file_inclusion_specification
         if ENV['SPEC']
           FileList[ ENV['SPEC']].sort
-        elsif File.exist?(pattern)
-          # The provided pattern is a directory or a file, not a file glob. Historically, this
-          # worked because `FileList[some_dir]` would return `[some_dir]` which would
-          # get passed to `rspec` and cause it to load files under that dir that match
-          # the default pattern. To continue working, we need to pass it on to `rspec`
-          # directly rather than treating it as a `--pattern` option.
+        elsif Array === pattern || File.exist?(pattern)
+          # Before RSpec 3.1, we used `FileList` to get the list of matched files, and
+          # then pass that along to the `rspec` command. Starting with 3.1, we prefer to
+          # pass along the pattern as-is to the `rspec` command, for 3 reasons:
+          #
+          #   * It's *much* less verbose to pass one `--pattern` option than a long list of files.
+          #   * It ensures `task.pattern` and `--pattern` have the same behavior.
+          #   * It fixes a bug, where `task.pattern = pattern_that_matches_no_files` would run
+          #     *all* files because it would cause no pattern or file args to get passed to `rspec`,
+          #     which causes all files to get run.
+          #
+          # However, `FileList` is *far* more flexible than the `--pattern` option. Specifically, it
+          # supports individual files and directories, as well as arrays of files, directories and globs.
+          #
+          # For backwards compatibility, we have to fall back to using FileList if the user has passed
+          # a `pattern` option that will not work with `--pattern`.
           #
           # TODO: consider deprecating support for this and removing it in RSpec 4.
-          pattern.shellescape
+          FileList[pattern].sort.map(&:shellescape)
         else
           "--pattern #{pattern.shellescape}"
         end

spec/rspec/core/rake_task_spec.rb

@@ -166,24 +166,60 @@ def self.it_configures_rspec_load_path(description, path_template)
       specify_consistent_ordering_of_files_to_run('a/*.rb', Dir)
     end
 
-    context "with a pattern that matches no files" do
-      it "runs nothing" do
-        task.pattern = 'a/*.no_match'
-        expect(loaded_files).to eq([])
+    context "with a pattern value" do
+      context "that matches no files" do
+        it "runs nothing" do
+          task.pattern = 'a/*.no_match'
+          expect(loaded_files).to eq([])
+        end
       end
-    end
 
-    context "with a pattern value that is an existing directory, not a file glob" do
-      it "loads the spec files in that directory" do
-        task.pattern = "./spec/rspec/core/resources/acceptance"
-        expect(loaded_files).to eq(["./spec/rspec/core/resources/acceptance/foo_spec.rb"])
+      context "that is an existing directory, not a file glob" do
+        it "loads the spec files in that directory" do
+          task.pattern = "./spec/rspec/core/resources/acceptance"
+          expect(loaded_files).to eq(["./spec/rspec/core/resources/acceptance/foo_spec.rb"])
+        end
       end
-    end
 
-    context "with a pattern value that is an existing file, not a file glob" do
-      it "loads the spec file" do
-        task.pattern = "./spec/rspec/core/resources/acceptance/foo_spec.rb"
-        expect(loaded_files).to eq(["./spec/rspec/core/resources/acceptance/foo_spec.rb"])
+      context "that is an existing file, not a file glob" do
+        it "loads the spec file" do
+          task.pattern = "./spec/rspec/core/resources/acceptance/foo_spec.rb"
+          expect(loaded_files).to eq(["./spec/rspec/core/resources/acceptance/foo_spec.rb"])
+        end
+      end
+
+      context "that is an array of existing files or directories, not a file glob" do
+        it "loads the specified spec files, and spec files from the specified directories" do
+          task.pattern = ["./spec/rspec/core/resources/acceptance", "./spec/rspec/core/resources/a_bar.rb"]
+
+          expect(loaded_files).to contain_exactly(
+            "./spec/rspec/core/resources/acceptance/foo_spec.rb",
+            "./spec/rspec/core/resources/a_bar.rb"
+          )
+        end
+      end
+
+      context "that is an array of globs relative to the current working dir" do
+        it "loads spec files that match any of the globs" do
+          task.pattern = ["./spec/rspec/core/resources/acceptance/*_spec.rb",
+                          "./spec/rspec/core/resources/*_bar.rb"]
+
+          expect(loaded_files).to contain_exactly(
+            "./spec/rspec/core/resources/acceptance/foo_spec.rb",
+            "./spec/rspec/core/resources/a_bar.rb"
+          )
+        end
+      end
+
+      context "that is a mixture of file globs and individual files or dirs" do
+        it "loads all specified or matching files" do
+          task.pattern = ["./spec/rspec/core/resources/acceptance/*_spec.rb", "./spec/rspec/core/resources/a_bar.rb"]
+
+          expect(loaded_files).to contain_exactly(
+            "./spec/rspec/core/resources/acceptance/foo_spec.rb",
+            "./spec/rspec/core/resources/a_bar.rb"
+          )
+        end
       end
     end